From: aaron Date: Fri, 17 Mar 2000 18:15:11 +0000 (+0000) Subject: Remove hard sentence breaks. X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=8c9265831a8817876fd3841a50242084667da47a;p=openbsd Remove hard sentence breaks. --- diff --git a/bin/cat/cat.1 b/bin/cat/cat.1 index 89d402195dc..e6477f2b3ac 100644 --- a/bin/cat/cat.1 +++ b/bin/cat/cat.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: cat.1,v 1.17 2000/03/02 04:17:50 aaron Exp $ +.\" $OpenBSD: cat.1,v 1.18 2000/03/17 18:15:11 aaron Exp $ .\" $NetBSD: cat.1,v 1.12 1995/09/27 05:38:55 cgd Exp $ .\" .\" Copyright (c) 1989, 1990, 1993 @@ -74,9 +74,11 @@ option but doesn't count blank lines. Displays non-printing characters so they are visible. Control characters print as .Ql ^X -for control-X. The only exception is the tab character, control-I (see the +for control-X. +The only exception is the tab character, control-I (see the .Fl t -option). The +option). +The .Tn DEL character (octal 0177) prints as .Ql ^? . @@ -129,11 +131,9 @@ to the file .Ar file3 , truncating .Ar file3 -if it already exists. See the manual page for your shell -.Po -i.e., -.Xr sh 1 -.Pc +if it already exists. +See the manual page for your shell (i.e., +.Xr sh 1 ) for more information on redirection. .Pp The command: diff --git a/bin/chio/chio.1 b/bin/chio/chio.1 index adb7414fc5c..05531bc8842 100644 --- a/bin/chio/chio.1 +++ b/bin/chio/chio.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: chio.1,v 1.13 1999/08/17 14:03:59 aaron Exp $ +.\" $OpenBSD: chio.1,v 1.14 2000/03/17 18:15:12 aaron Exp $ .\" $NetBSD: chio.1,v 1.1.1.1 1996/04/03 00:34:38 thorpej Exp $ .\" .\" Copyright (c) 1996 Jason R. Thorpe @@ -76,11 +76,13 @@ There are four element types: .Pa portal (import/export), and .Pa drive -(data transfer). In this command description, the shorthand +(data transfer). +In this command description, the shorthand .Sq ET will be used to represent an element type, and .Sq EU -will be used to represent an element unit. For example, to represent +will be used to represent an element unit. +For example, to represent the first robotic arm in the changer, the ET would be .Dq picker and the EU would be @@ -113,7 +115,8 @@ is specified, the media unit will be inverted before insertion. .Op Ar inv1 .Op Ar inv2 .Pp -Performs a media unit exchange operation. The media unit in +Performs a media unit exchange operation. +The media unit in .Aq Ar src ET/EU is moved to .Aq Ar dst1 ET/EU @@ -172,7 +175,8 @@ Configure the changer to use picker .Cm chio status .Op Aq Ar type .Pp -Report the status of all elements in the changer. If +Report the status of all elements in the changer. +If .Aq Ar type is specified, report the status of all elements of type .Aq Ar type . diff --git a/bin/chmod/chmod.1 b/bin/chmod/chmod.1 index c0455993b6e..bb425f13f5e 100644 --- a/bin/chmod/chmod.1 +++ b/bin/chmod/chmod.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: chmod.1,v 1.15 1999/09/23 09:56:53 aaron Exp $ +.\" $OpenBSD: chmod.1,v 1.16 2000/03/17 18:15:12 aaron Exp $ .\" $NetBSD: chmod.1,v 1.8 1995/03/21 09:02:07 cgd Exp $ .\" .\" Copyright (c) 1989, 1990, 1993, 1994 @@ -57,7 +57,8 @@ The utility modifies the file mode bits of the listed files as specified by the .Ar mode -operand. The mode of a file dictates its permissions, among other attributes. +operand. +The mode of a file dictates its permissions, among other attributes. .Pp The options are as follows: .Bl -tag -width Ds @@ -164,9 +165,10 @@ and .Pp The execute bit for a directory is often referred to as the .Dq search -bit. In order to access a file, a user must have execute permission in each -directory leading up to it in the filesystem hierarchy. For example, to access -the file +bit. +In order to access a file, a user must have execute permission in each +directory leading up to it in the filesystem hierarchy. +For example, to access the file .Pa /bin/ls , execute permission is needed on .Pa / , @@ -332,32 +334,32 @@ Make a file readable by anyone and writable by the owner only. .Pp Deny write permission to group and others. .Pp -.Dl Ic chmod go-w file +.Dl Ic chmod go-w file .Pp Set the read and write permissions to the usual defaults, but retain any execute permissions that are currently set. .Pp -.Dl Ic chmod =rw,+X file +.Dl Ic chmod =rw,+X file .Pp Make a directory or file searchable/executable by everyone if it is already searchable/executable by anyone. .Pp -.Dl Ic chmod +X file +.Dl Ic chmod +X file .Pp Any of the following will make a file readable/executable by everyone and writable by the owner only. .Pp -.Dl Ic chmod 755 file -.Dl Ic chmod u=rwx,go=rx file -.Dl Ic chmod u=rwx,go=u-w file +.Dl Ic chmod 755 file +.Dl Ic chmod u=rwx,go=rx file +.Dl Ic chmod u=rwx,go=u-w file .Pp Clear all mode bits for group and others. .Pp -.Dl Ic chmod go= file +.Dl Ic chmod go= file .Pp Set the group bits equal to the user bits, but clear the group write bit. .Pp -.Dl Ic chmod g=u-w file +.Dl Ic chmod g=u-w file .Sh SEE ALSO .Xr chgrp 1 , .Xr find 1 , diff --git a/bin/cp/cp.1 b/bin/cp/cp.1 index 1d478e4a6a5..f50e70e3fbd 100644 --- a/bin/cp/cp.1 +++ b/bin/cp/cp.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: cp.1,v 1.13 1999/09/23 19:27:35 aaron Exp $ +.\" $OpenBSD: cp.1,v 1.14 2000/03/17 18:15:11 aaron Exp $ .\" $NetBSD: cp.1,v 1.9 1995/07/25 19:36:45 jtc Exp $ .\" .\" Copyright (c) 1989, 1990, 1993, 1994 @@ -104,7 +104,8 @@ option is also specified, no symbolic links are followed. .It Fl f For each existing destination pathname, remove it and create a new file, without prompting for confirmation, -regardless of its permissions. This option overrides any use of +regardless of its permissions. +This option overrides any use of .Fl i . .It Fl i Write a prompt to the standard error output before copying a file diff --git a/bin/csh/csh.1 b/bin/csh/csh.1 index 7ca64b30ef6..9f6f18509ec 100644 --- a/bin/csh/csh.1 +++ b/bin/csh/csh.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: csh.1,v 1.32 2000/01/18 21:03:43 aaron Exp $ +.\" $OpenBSD: csh.1,v 1.33 2000/03/17 18:15:12 aaron Exp $ .\" $NetBSD: csh.1,v 1.10 1995/03/21 09:02:35 cgd Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 @@ -56,7 +56,8 @@ job control facilities (see interactive file name and user name completion (see .Sx File name completion ) , -and a C-like syntax. It is used both as an interactive +and a C-like syntax. +It is used both as an interactive login shell and a shell script command processor. .Ss Argument list processing If the first argument (argument 0) to the shell is a dash @@ -102,12 +103,13 @@ is the only flag specified). .It Fl m Read .Pa \&.cshrc , -regardless of its owner and group. This option is dangerous and should only -be used by +regardless of its owner and group. +This option is dangerous and should only be used by .Xr su 1 . .It Fl n Commands are parsed, but not executed. -This aids in syntactic checking of shell scripts. When used interactively, the +This aids in syntactic checking of shell scripts. +When used interactively, the shell can be terminated by pressing control-D (end-of-file character), since .Ic exit will not work. @@ -293,11 +295,11 @@ respectively. (See .Ss Jobs The shell associates a .Em job -with each pipeline. It keeps -a table of current jobs, printed by the +with each pipeline. +It keeps a table of current jobs, printed by the .Ic jobs -command, and assigns them small integer numbers. When -a job is started asynchronously with +command, and assigns them small integer numbers. +When a job is started asynchronously with .Ql & , the shell prints a line that looks like: @@ -316,8 +318,8 @@ If you are running a job and wish to do something else you may hit signal to the current job. The shell will then normally show that the job has been .Dq Stopped , -and print another prompt. You can then manipulate the state of this job, -putting it in the +and print another prompt. +You can then manipulate the state of this job, putting it in the .Em background with the .Ic bg @@ -331,7 +333,8 @@ A .Ic ^Z takes effect immediately and is like an interrupt in that pending output and unread input are discarded -when it is typed. There is another special key +when it is typed. +There is another special key .Ic ^Y that does not generate a .Dv SIGSTOP @@ -342,17 +345,19 @@ This request can usefully be typed ahead when you have prepared some commands for a job that you wish to stop after it has read them. .Pp A job being run in the background will stop if it tries to read -from the terminal. Background jobs are normally allowed to produce output, +from the terminal. +Background jobs are normally allowed to produce output, but this can be disabled by giving the command .Ic stty tostop . If you set this tty option, then background jobs will stop when they try to produce output like they do when they try to read input. .Pp -There are several ways to refer to jobs in the shell. The character +There are several ways to refer to jobs in the shell. +The character .Ql % -introduces a job name. If you wish to refer to job number 1, you can -name it as +introduces a job name. +If you wish to refer to job number 1, you can name it as .Ql %1 . Just naming a job brings it to the foreground; thus .Ic %1 @@ -385,8 +390,8 @@ The abbreviation .Ql %+ refers to the current job and .Ql %\- -refers to the previous job. For close -analogy with the syntax of the +refers to the previous job. +For close analogy with the syntax of the .Ic history mechanism (described below), .Ql %% @@ -396,12 +401,14 @@ The job control mechanism requires that the .Xr stty 1 option .Ic new -be set. It is an artifact from a +be set. +It is an artifact from a .Em new implementation of the tty driver that allows generation of interrupt characters from -the keyboard to tell jobs to stop. See +the keyboard to tell jobs to stop. +See .Xr stty 1 for details on setting options in the new tty driver. @@ -409,7 +416,8 @@ on setting options in the new tty driver. This shell learns immediately whenever a process changes state. It normally informs you whenever a job becomes blocked so that no further progress is possible, but only just before it prints -a prompt. This is done so that it does not otherwise disturb your work. +a prompt. +This is done so that it does not otherwise disturb your work. If, however, you set the shell variable .Va notify , the shell will notify you immediately of changes of status in background @@ -417,7 +425,8 @@ jobs. There is also a shell command .Ic notify that marks a single process so that its status changes will be immediately -reported. By default +reported. +By default .Ic notify marks the current process; simply say @@ -429,7 +438,8 @@ be warned that .Dq You have stopped jobs . You may use the .Ic jobs -command to see what they are. If you do this or immediately try to +command to see what they are. +If you do this or immediately try to exit again, the shell will not warn you a second time, and the suspended jobs will be terminated. .Ss File name completion @@ -480,8 +490,8 @@ incomplete, since there are two file names matching the prefix If a partial file name is followed by the end-of-file character (usually control-D), then, instead of completing the name, .Nm -will list all file names matching the prefix. For example, -the input +will list all file names matching the prefix. +For example, the input .Pp .Dl % vi D .Pp @@ -510,11 +520,13 @@ can be inhibited by setting the variable .Va nobeep . .Pp Normally, all files in the particular directory are candidates -for name completion. Files with certain suffixes can be excluded +for name completion. +Files with certain suffixes can be excluded from consideration by setting the variable .Va fignore to the -list of suffixes to be ignored. Thus, if +list of suffixes to be ignored. +Thus, if .Va fignore is set by the command @@ -534,10 +546,11 @@ ignoring the files and .Qq xmpl.out . However, if the only completion possible requires not ignoring these -suffixes, then they are not ignored. In addition, +suffixes, then they are not ignored. +In addition, .Va fignore -does not affect the listing of file names by control-D. All files -are listed regardless of their suffixes. +does not affect the listing of file names by control-D. +All files are listed regardless of their suffixes. .Ss Substitutions We now describe the various transformations the shell performs on the input in the order in which they occur. @@ -704,7 +717,8 @@ Apply the change once on each word, prefixing the above; e.g., .Ql g& . .It a Apply the change as many times as possible on a single word, prefixing -the above. It can be used together with +the above. +It can be used together with .Ql g to apply a substitution globally. .It p @@ -720,8 +734,8 @@ but break into words at blanks, tabs and newlines. Unless preceded by a .Ql g the change is applied only to the first -modifiable word. With substitutions, it is an error for no word to be -applicable. +modifiable word. +With substitutions, it is an error for no word to be applicable. .Pp The left-hand side of substitutions are not regular expressions in the sense of the editors, but instead strings. @@ -964,7 +978,8 @@ Braces insulate .Ar name from following characters that would otherwise be part of it. Shell variables have names consisting of up to 20 letters and digits -starting with a letter. The underscore character is considered a letter. +starting with a letter. +The underscore character is considered a letter. If .Ar name is not a shell variable, but is set in the environment, then @@ -1149,7 +1164,7 @@ When followed by a name consisting of letters, digits and .Ql \- characters, the shell searches for a user with that name and substitutes their -home directory; thus +home directory; thus .Dq ~ken might expand to .Dq /usr/ken @@ -1297,7 +1312,8 @@ Note that the default standard input for a command run detached is modified to be the empty file .Pa /dev/null ; instead the standard input -remains as the original standard input of the shell. If this is a terminal +remains as the original standard input of the shell. +If this is a terminal and if the process attempts to read from the terminal, then the process will block and the user will be notified (see .Sx Jobs @@ -1371,8 +1387,8 @@ hand side is a .Ar pattern (containing, e.g., *'s, ?'s, and instances of .Dq [...] ) -against which the left-hand operand is matched. This reduces the -need for use of the +against which the left-hand operand is matched. +This reduces the need for use of the .Ar switch statement in shell scripts when all that is really needed is pattern matching. .Pp @@ -1486,7 +1502,8 @@ or Shows the amount of dynamic memory acquired, broken down into used and free memory. With an argument shows the number of free and used blocks in each size -category. The categories start at size 8 and double at each step. +category. +The categories start at size 8 and double at each step. This command's output may vary across system types, since systems other than the .Tn VAX @@ -1590,7 +1607,8 @@ The arguments are read as input to the shell and the resulting command(s) executed in the context of the current shell. This is usually used to execute commands generated as the result of command or variable substitution, since -parsing occurs before these substitutions. See +parsing occurs before these substitutions. +See .Xr tset 1 for an example of using .Ic eval . @@ -1804,11 +1822,12 @@ is given, then the current limit is printed; if no .Ar resource is given, then -all limitations are given. If the +all limitations are given. +If the .Fl h -flag is given, the hard limits are used instead of the current -limits. The hard limits impose a ceiling on the values of -the current limits. Only the super-user may raise the hard limits, +flag is given, the hard limits are used instead of the current limits. +The hard limits impose a ceiling on the values of the current limits. +Only the super-user may raise the hard limits, but a user may lower or raise the current limits within the legal range. .Pp Resources controllable currently include @@ -1830,7 +1849,8 @@ size of the automatically extended stack region), and The .Ar maximum-use may be given as a (floating point or integer) -number followed by a scale factor. For all limits other than +number followed by a scale factor. +For all limits other than .Ar cputime the default scale is .Ql k @@ -1913,7 +1933,8 @@ are effectively .It Ic notify % Ns Ar job ... Causes the shell to notify the user asynchronously when the status of the current or specified jobs change; normally notification is presented -before a prompt. This is automatic if the shell variable +before a prompt. +This is automatic if the shell variable .Va notify is set. .Pp @@ -1986,17 +2007,19 @@ With a numeric argument, rotates the .Ar n Ns \'th argument of the directory -stack around to be the top element and changes to it. The members +stack around to be the top element and changes to it. +The members of the directory stack are numbered from the top starting at 0. .Pp .It Ic rehash Causes the internal hash table of the contents of the directories in the .Va path -variable to be recomputed. This is needed if new commands are added -to directories in the +variable to be recomputed. +This is needed if new commands are added to directories in the .Ic path -while you are logged in. This should only be necessary if you add +while you are logged in. +This should only be necessary if you add commands to one of your own directories, or if a systems programmer changes the contents of a system directory. .Pp @@ -2059,7 +2082,8 @@ The last form sets the value of environment variable .Ar name to be .Ar value , -a single string. The second form sets +a single string. +The second form sets .Ar name to an empty string. The most commonly used environment variables @@ -2161,13 +2185,16 @@ If arguments are given the specified simple command is timed and a time summary as described under the .Ic time -variable is printed. If necessary, an extra shell is created to print the time +variable is printed. +If necessary, an extra shell is created to print the time statistic when the command completes. .Pp .It Ic umask .It Ic umask Ar value The file creation mask is displayed (first form) or set to the specified -value (second form). The mask is given in octal. Common values for +value (second form). +The mask is given in octal. +Common values for the mask are 002 giving all access to the group and read and execute access to others or 022 giving all access except write access for users in the group or others. @@ -2184,7 +2211,7 @@ Use of the internal hash table to speed location of executed programs is disabled. .Pp .It Ic unlimit -.It Ic unlimit Ar resource +.It Ic unlimit Ar resource .It Ic unlimit Fl h .It Ic unlimit Fl h Ar resource Removes the limitation on @@ -2193,10 +2220,11 @@ If no .Ar resource is specified, then all .Ar resource -limitations are removed. If +limitations are removed. +If .Fl h -is given, the corresponding hard limits are removed. Only the -super-user may do this. +is given, the corresponding hard limits are removed. +Only the superuser may do this. .Pp .It Ic unset Ar pattern All variables whose names match the specified pattern are removed. @@ -2209,7 +2237,8 @@ It is not an error for nothing to be .Pp .It Ic unsetenv Ar pattern Removes all variables whose name match the specified pattern from the -environment. See also the +environment. +See also the .Ic setenv command above and .Xr printenv 1 . @@ -2370,7 +2399,8 @@ since these substitutions are then done selectively. Enable file name completion. .It Ic histchars Can be given a string value to change the characters used in history -substitution. The first character of its value is used as the +substitution. +The first character of its value is used as the history substitution character, replacing the default character .Ql ! . The second character of its value replaces the character @@ -2471,7 +2501,8 @@ variable after reading .Ar \&.cshrc , and each time the .Ar path -variable is reset. If new commands are added to these directories +variable is reset. +If new commands are added to these directories while the shell is active, it may be necessary to do a .Ic rehash or the commands may not be found. @@ -2701,7 +2732,8 @@ Shell built-in functions are not stoppable/restartable. Command sequences of the form .Dq a \&; b \&; c are also not handled gracefully -when stopping is attempted. If you suspend +when stopping is attempted. +If you suspend .Ql b , the shell will immediately execute .Ql c . @@ -2713,7 +2745,8 @@ a sub-shell; i.e., .Pp Control over tty output after processes are started is primitive; perhaps this will inspire someone to work on a good virtual -terminal interface. In a virtual terminal interface much more +terminal interface. +In a virtual terminal interface much more interesting things could be done with output control. .Pp Alias substitution is most often used to clumsily simulate shell procedures; @@ -2725,7 +2758,8 @@ are not placed on the .Ic history list. Control structure should be parsed instead of being recognized as built-in -commands. This would allow control commands to be placed anywhere, +commands. +This would allow control commands to be placed anywhere, to be combined with .Ql | , and to be used with diff --git a/bin/df/df.1 b/bin/df/df.1 index 630439493c9..5e899849575 100644 --- a/bin/df/df.1 +++ b/bin/df/df.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: df.1,v 1.21 2000/03/05 00:28:51 aaron Exp $ +.\" $OpenBSD: df.1,v 1.22 2000/03/17 18:15:12 aaron Exp $ .\" $NetBSD: df.1,v 1.12 1995/12/05 02:42:45 jtc Exp $ .\" .\" Copyright (c) 1989, 1990, 1993 @@ -71,7 +71,8 @@ options below). The options are as follows: .Bl -tag -width Ds .It Fl h -"Human-readable" output. Use unit suffixes: Byte, Kilobyte, Megabyte, +"Human-readable" output. +Use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte, Petabyte, Exabyte in order to reduce the number of digits to four or less. .It Fl i @@ -84,7 +85,8 @@ option causes the numbers to be reported in kilobyte counts. .It Fl l Display statistics only about mounted file systems with the .Dv MNT_LOCAL -flag set. If a non-local file system is given as an argument, a +flag set. +If a non-local file system is given as an argument, a warning is issued and no information is given on that file system. .It Fl n Print out the previously obtained statistics from the file systems. @@ -107,7 +109,8 @@ The list of filesystem types can be prefixed with .Dq no to specify the filesystem types for which action should .Em not -be taken. If a file system is given on the command line that is not of +be taken. +If a file system is given on the command line that is not of the specified type, a warning is issued and no information is given on that file system. .El diff --git a/bin/domainname/domainname.1 b/bin/domainname/domainname.1 index 221f9c4664e..252cc3444d7 100644 --- a/bin/domainname/domainname.1 +++ b/bin/domainname/domainname.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: domainname.1,v 1.9 1999/10/05 19:59:12 ericj Exp $ +.\" $OpenBSD: domainname.1,v 1.10 2000/03/17 18:15:13 aaron Exp $ .\" $NetBSD: domainname.1,v 1.7 1995/07/25 19:36:57 jtc Exp $ .\" .\" Copyright (c) 1983, 1988, 1990, 1993 @@ -46,10 +46,11 @@ .Sh DESCRIPTION The .Nm -utility prints the YP domain name of the current host. The super-user can -set the domain name by supplying a +utility prints the YP domain name of the current host. +The superuser can set the domain name by supplying a .Pa /etc/defaultdomain -file. This is used at system boot time by +file. +This is used at system boot time by .Xr /etc/rc 8 to initialize the domainname. .Sh SEE ALSO diff --git a/bin/ed/ed.1 b/bin/ed/ed.1 index 338393533f9..eec55179635 100644 --- a/bin/ed/ed.1 +++ b/bin/ed/ed.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: ed.1,v 1.20 1999/07/04 18:59:37 aaron Exp $ +.\" $OpenBSD: ed.1,v 1.21 2000/03/17 18:15:13 aaron Exp $ .\" .Dd May 2, 1993 .Dt ED 1 @@ -59,12 +59,12 @@ When an input command, such as .Em c (change), is given, .Nm -enters input mode. This is the primary means -of adding text to a file. +enters input mode. +This is the primary means of adding text to a file. In this mode, no commands are available; instead, the standard input is written -directly to the editor buffer. Lines consist of text up to and -including a +directly to the editor buffer. +Lines consist of text up to and including a .Em newline character. Input mode is terminated by @@ -81,7 +81,8 @@ command deletes lines; the .Em m command moves lines, and so on. It is possible to modify only a portion of a line by means of replacement, -as in the example above. However, even here, the +as in the example above. +However, even here, the .Em s command is applied to whole lines at a time. .Pp @@ -95,13 +96,15 @@ commands have the structure: .Ed .Pp The address(es) indicate the line or range of lines to be affected by the -command. If fewer addresses are given than the command accepts, then +command. +If fewer addresses are given than the command accepts, then default addresses are supplied. .Pp .Ss OPTIONS .Bl -tag -width Ds .It Fl s -Suppresses diagnostics. This should be used if +Suppresses diagnostics. +This should be used if .Nm standard input is from a script. .It Fl x @@ -110,18 +113,19 @@ Prompts for an encryption key to be used in subsequent reads and writes .Em x command). .It Fl p Ar string -Specifies a command prompt. This may be toggled on and off with the +Specifies a command prompt. +This may be toggled on and off with the .Em P command. .It Ar file -Specifies the name of a file to read. If +Specifies the name of a file to read. +If .Ar file is prefixed with a bang .Pq Ql \&! , -then it is interpreted as a shell command. In this case, -what is read is -the standard output of +then it is interpreted as a shell command. +In this case, what is read is the standard output of .Ar file executed via .Xr sh 1 . @@ -141,13 +145,14 @@ maintains a which is typically supplied to commands as the default address when none is specified. When a file is first read, the current address is set to the last line -of the file. In general, the current address is set to the last line +of the file. +In general, the current address is set to the last line affected by a command. .Pp A line address is constructed from one of the bases in the list below, optionally followed -by a numeric offset. The offset may include any combination -of digits, operators (i.e., +by a numeric offset. +The offset may include any combination of digits, operators (i.e., .Em + , .Em - @@ -166,9 +171,12 @@ This means "before the first line," and is legal wherever it makes sense. .Pp An address range is two addresses separated either by a comma or -semi-colon. The value of the first address in a range cannot exceed the -value of the second. If only one address is given in a range, then -the second address is set to the given address. If an +semi-colon. +The value of the first address in a range cannot exceed the +value of the second. +If only one address is given in a range, then +the second address is set to the given address. +If an .Em n Ns No -tuple of addresses is given where .Em n > 2, @@ -178,7 +186,8 @@ the If only one address is expected, then the last address is used. .Pp Each address in a comma-delimited range is interpreted relative to the -current address. In a semi-colon-delimited range, the first address is +current address. +In a semi-colon-delimited range, the first address is used to set the current address, and the second address is interpreted relative to the first. .Pp @@ -221,13 +230,13 @@ next line, where .Em n is a non-negative number. .It Em \&, No or Em % -The first through last lines in the buffer. This is equivalent to -the address range +The first through last lines in the buffer. +This is equivalent to the address range .Em 1,$. .It Em \&; The -current through last lines in the buffer. This is equivalent to -the address range +current through last lines in the buffer. +This is equivalent to the address range .Em .,$. .It Em / Ns No re Ns Em / The @@ -272,7 +281,8 @@ command for selecting old text to be replaced with new. .Pp In addition to a specifying string literals, regular expressions can represent -classes of strings. Strings thus represented are said to be matched +classes of strings. +Strings thus represented are said to be matched by the corresponding regular expression. If it is possible for a regular expression to match several strings in a line, then the left-most longest match is @@ -395,11 +405,13 @@ Subexpressions are ordered relative to their left delimiter. .It Em * Matches the single character regular expression or subexpression -immediately preceding it zero or more times. If +immediately preceding it zero or more times. +If .Em * is the first character of a regular expression or subexpression, then it matches -itself. The +itself. +The .Em * operator sometimes yields unexpected results. For example, the regular expression @@ -453,7 +465,8 @@ An interrupt (typically ^C) has the effect of aborting the current command and returning the editor to command mode. .Pp .Nm -recognizes the following commands. The commands are shown together with +recognizes the following commands. +The commands are shown together with the default address or address range supplied if none is specified (in parenthesis), and other possible arguments on the right. .Bl -tag -width Dxxs @@ -462,14 +475,16 @@ Appends text to the buffer after the addressed line. Text is entered in input mode. The current address is set to last line entered. .It (.,.) Ns Em c -Changes lines in the buffer. The addressed lines are deleted +Changes lines in the buffer. +The addressed lines are deleted from the buffer, and text is appended in their place. Text is entered in input mode. The current address is set to last line entered. .It (.,.) Ns Em d Deletes the addressed lines from the buffer. If there is a line after the deleted range, then the current address is set -to this line. Otherwise the current address is set to the line +to this line. +Otherwise the current address is set to the line before the deleted range. .It Em e No file Edits @@ -555,7 +570,8 @@ The format of .Em command-list is the same as that of the .Em g -command. A newline alone acts as a null command list. +command. +A newline alone acts as a null command list. A single .Em & repeats the last non-null command list. @@ -573,7 +589,8 @@ Inserts text in the buffer before the current line. Text is entered in input mode. The current address is set to the last line entered. .It (.,.+1) Ns Em j -Joins the addressed lines. The addressed lines are +Joins the addressed lines. +The addressed lines are deleted from the buffer and replaced by a single line containing their joined text. The current address is set to the resultant line. @@ -598,7 +615,8 @@ before displaying the next screen. The current address is set to the last line printed. .It (.,.) Ns Em m Ns No (.) -Moves lines in the buffer. The addressed lines are moved to after the +Moves lines in the buffer. +The addressed lines are moved to after the right-hand destination address, which may be the address .Em 0 (zero). @@ -606,11 +624,11 @@ The current address is set to the last line moved. .It (.,.) Ns Em n Prints the addressed lines along with -their line numbers. The current address is set to the last line -printed. +their line numbers. +The current address is set to the last line printed. .It (.,.) Ns Em p -Prints the addressed lines. The current address is set to the last line -printed. +Prints the addressed lines. +The current address is set to the last line printed. .It Em P Toggles the command prompt on and off. Unless a prompt was specified by with command-line option @@ -630,10 +648,12 @@ except that unwritten changes are discarded without warning. .It ($) Ns Em r No file Reads .Em file -to after the addressed line. If +to after the addressed line. +If .Em file is not specified, then the default -filename is used. If there was no default filename prior to the command, +filename is used. +If there was no default filename prior to the command, then the default filename is set to .Em file Ns No . Otherwise, the default filename is unchanged. @@ -776,7 +796,8 @@ Any previous contents of is lost without warning. If there is no default filename, then the default filename is set to .Em file Ns No , -otherwise it is unchanged. If no filename is specified, then the default +otherwise it is unchanged. +If no filename is specified, then the default filename is used. The current address is unchanged. .It (1,$) Ns Em wq No file @@ -801,15 +822,18 @@ command, expect that the previous contents of file is not clobbered. The current address is unchanged. .It Em x Prompts for an encryption key which is used in subsequent reads and -writes. If a newline alone is entered as the key, then encryption is -turned off. Otherwise, echoing is disabled while a key is read. +writes. +If a newline alone is entered as the key, then encryption is +turned off. +Otherwise, echoing is disabled while a key is read. Encryption/decryption is done using the .Xr bdes 1 algorithm. .It (.+1) Ns Em z Ns No n Scrolls .Em n -lines at a time starting at addressed line. If +lines at a time starting at addressed line. +If .Em n is not specified, then the current window size is used. The current address is set to the last line printed. @@ -877,7 +901,8 @@ interpreted literally. If a text (non-binary) file is not terminated by a newline character, then .Nm -appends one on reading/writing it. In the case of a binary file, +appends one on reading/writing it. +In the case of a binary file, .Nm does not append a newline on reading/writing. .Sh DIAGNOSTICS diff --git a/bin/expr/expr.1 b/bin/expr/expr.1 index 1a95bf52868..169addc3c3f 100644 --- a/bin/expr/expr.1 +++ b/bin/expr/expr.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: expr.1,v 1.8 1999/09/23 10:43:07 aaron Exp $ +.\" $OpenBSD: expr.1,v 1.9 2000/03/17 18:15:13 aaron Exp $ .\" $NetBSD: expr.1,v 1.9 1995/04/28 23:27:13 jtc Exp $ .\" .\" Written by J.T. Conklin . @@ -55,7 +55,8 @@ operator matches .Ar expr1 against .Ar expr2 , -which must be a regular expression. The regular expression is anchored +which must be a regular expression. +The regular expression is anchored to the beginning of the string with an implicit .Ql ^ . .Pp diff --git a/bin/hostname/hostname.1 b/bin/hostname/hostname.1 index 13e7938195e..e0d3df53848 100644 --- a/bin/hostname/hostname.1 +++ b/bin/hostname/hostname.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: hostname.1,v 1.9 1999/10/05 19:58:31 ericj Exp $ +.\" $OpenBSD: hostname.1,v 1.10 2000/03/17 18:15:13 aaron Exp $ .\" $NetBSD: hostname.1,v 1.11 1995/09/07 06:28:39 jtc Exp $ .\" .\" Copyright (c) 1983, 1988, 1990, 1993 @@ -47,10 +47,11 @@ .Sh DESCRIPTION The .Nm -utility prints the name of the current host. The super-user can -set the host name by supplying a +utility prints the name of the current host. +The superuser can set the host name by supplying a .Pa /etc/myname -file. This is used at system boot time by +file. +This is used at system boot time by .Xr /etc/rc 8 to initialize the hostname. .Pp diff --git a/bin/kill/kill.1 b/bin/kill/kill.1 index 40aa2bb5a22..c6a5c4a42fc 100644 --- a/bin/kill/kill.1 +++ b/bin/kill/kill.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: kill.1,v 1.11 1999/09/23 10:50:45 aaron Exp $ +.\" $OpenBSD: kill.1,v 1.12 2000/03/17 18:15:14 aaron Exp $ .\" $NetBSD: kill.1,v 1.8 1995/09/07 06:30:26 jtc Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 @@ -130,7 +130,7 @@ so process IDs are not as often used as .Nm arguments. See -.Xr csh 1 +.Xr csh 1 for details. .Sh SEE ALSO .Xr csh 1 , @@ -152,5 +152,5 @@ command appeared in A replacement for the command .Dq Li kill 0 for -.Xr csh 1 +.Xr csh 1 users should be provided. diff --git a/bin/ksh/ksh.1 b/bin/ksh/ksh.1 index 4e843d2e9ff..0273e68a0f0 100644 --- a/bin/ksh/ksh.1 +++ b/bin/ksh/ksh.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: ksh.1,v 1.30 2000/03/14 20:25:46 aaron Exp $ +.\" $OpenBSD: ksh.1,v 1.31 2000/03/17 18:15:16 aaron Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -51,7 +51,8 @@ .Sh DESCRIPTION .Nm ksh is a command interpreter intended for both interactive and shell -script use. Its command language is a superset of the +script use. +Its command language is a superset of the .Xr sh 1 shell language. .Ss Shell startup @@ -81,8 +82,10 @@ If neither the nor the .Fl s option is specified, the first non-option argument specifies the name -of a file the shell reads commands from. If there are no non-option -arguments, the shell reads commands from the standard input. The name of +of a file the shell reads commands from. +If there are no non-option +arguments, the shell reads commands from the standard input. +The name of the shell (i.e., the contents of $0) is determined as follows: if the .Fl c option is used and there is a non-option argument, it is used as the name; @@ -94,8 +97,8 @@ A shell is if the .Fl i option is used or if both standard input and standard error are attached -to a tty. An interactive shell has job control enabled (if available), -ignores the +to a tty. +An interactive shell has job control enabled (if available), ignores the .Dv SIGINT , .Dv SIGQUIT , and @@ -171,9 +174,11 @@ A privileged shell does not process .Pa $HOME/.profile nor the .Ev ENV -parameter (see below). Instead, the file +parameter (see below). +Instead, the file .Pa /etc/suid_profile -is processed. Clearing the privileged option causes the shell to set +is processed. +Clearing the privileged option causes the shell to set its effective user ID (group ID) to its real user ID (group ID). .Pp If the basename of the name the shell is called with (i.e., argv[0]) @@ -196,7 +201,8 @@ after any profiles are processed), its value is subjected to parameter, command, arithmetic, and tilde .Pq Sq \&~ substitution and the resulting file -(if any) is read and executed. If the +(if any) is read and executed. +If the .Ev ENV parameter is not set (and not .Dv NULL ) @@ -209,7 +215,8 @@ mentioned substitutions have been performed). .Pp The exit status of the shell is 127 if the command file specified on the command line could not be opened, or non-zero if a fatal syntax error -occurred during the execution of a script. In the absence of fatal errors, +occurred during the execution of a script. +In the absence of fatal errors, the exit status is that of the last command executed, or zero, if no command is executed. .Ss Command syntax @@ -227,8 +234,8 @@ and .Ql \&) .Pc . Aside from delimiting words, spaces and tabs are ignored, while newlines -usually delimit commands. The meta-characters are used in building the -following tokens: +usually delimit commands. +The meta-characters are used in building the following tokens: .Ql < , .Ql <& , .Ql > , @@ -267,7 +274,8 @@ or in groups using double .Pq Sq \&" or single .Pq Sq \&' -quotes. Note that the following characters are also treated specially by the +quotes. +Note that the following characters are also treated specially by the shell and must be quoted if they are to represent themselves: .Ql \e , .Ql \&" , @@ -338,8 +346,10 @@ input/output redirections (see .Sx Input/output redirections below), and command words; the only restriction is that parameter assignments come -before any command words. The command words, if any, define the command -that is to be executed and its arguments. The command may be a shell built-in +before any command words. +The command words, if any, define the command +that is to be executed and its arguments. +The command may be a shell built-in command, a function or an external command (i.e., a separate executable file that is located using the .Ev PATH @@ -353,7 +363,8 @@ this is related to the status returned by be executed, the exit status is 126); the exit status of other command constructs (built-in commands, functions, compound-commands, pipelines, lists, etc.) are all well-defined and are described where the construct is -described. The exit status of a command consisting only of parameter +described. +The exit status of a command consisting only of parameter assignments is that of the last command substitution performed during the parameter assignment or 0 is there were no command substitutions. .Pp @@ -362,8 +373,9 @@ Commands can be chained together using the token to form pipelines, in which the standard output of each command but the last is piped (see .Xr pipe 2 ) -to the standard input of the following command. The exit status of a pipeline -is that of its last command. A pipeline may be prefixed by the +to the standard input of the following command. +The exit status of a pipeline is that of its last command. +A pipeline may be prefixed by the .Ql ! reversed word which causes the exit status of the pipeline to be logically complemented: if the original status was 0 the complemented status will be 1; @@ -399,13 +411,15 @@ have equal precedence which is higher than that of .Ql |& and .Ql \&; , -which also have equal precedence. The +which also have equal precedence. +The .Ql & token causes the preceding command to be executed asynchronously; that is, the shell starts the command but does not wait for it to complete (the shell does keep track of the status of asynchronous commands, see .Sx Job control -below). When an asynchronous command is started when job control is disabled +below). +When an asynchronous command is started when job control is disabled (i.e., in most scripts), the command is started with signals .Dv SIGINT and @@ -418,7 +432,8 @@ The operator starts a co-process which is a special kind of asynchronous process (see .Sx Co-processes -below). Note that a command must follow the +below). +Note that a command must follow the .Ql && and .Ql || @@ -430,7 +445,8 @@ or The exit status of a list is that of the last command executed, with the exception of asynchronous lists, for which the exit status is 0. .Pp -Compound commands are created using the following reserved words. These words +Compound commands are created using the following reserved words. +These words are only recognized if they are unquoted and if they are used as the first word of a command (i.e., they can't be preceded by parameter assignments or redirections): @@ -453,7 +469,8 @@ elif for select while } .Sy Note: Some shells (but not this one) execute control structure commands in a subshell when one or more of their file descriptors are redirected, so any -environment changes inside them may fail. To be portable, the +environment changes inside them may fail. +To be portable, the .Ic exec statement should be used instead to redirect file descriptors before the control structure. @@ -461,7 +478,8 @@ control structure. In the following compound command descriptions, command lists (denoted as .Em list ) that are followed by reserved words must end with a semicolon, a newline, or -a (syntactically correct) reserved word. For example, +a (syntactically correct) reserved word. +For example, .Pp .Bl -inset -indent -compact .It Ic { echo foo; echo bar; } @@ -480,12 +498,14 @@ is not. .It Ic \&( Ar list Ic \&) Execute .Ar list -in a subshell. There is no implicit way to pass environment changes from a +in a subshell. +There is no implicit way to pass environment changes from a subshell back to its parent. .It Ic \&{ Ar list Ic \&} Compound construct; .Ar list -is executed, but not in a subshell. Note that +is executed, but not in a subshell. +Note that .Ic \&{ and .Ic \&} @@ -505,19 +525,21 @@ against the specified .Ar pattern Ns s ; the .Ar list -associated with the first successfully matched pattern is executed. Patterns -used in +associated with the first successfully matched pattern is executed. +Patterns used in .Ic case statements are the same as those used for file name patterns except that the restrictions regarding .Ql \&. and .Ql / -are dropped. Note that any unquoted space before and after a pattern is -stripped; any space with a pattern must be quoted. Both the word and the -patterns are subject to parameter, command, and arithmetic substitution as -well as tilde substitution. For historical reasons, open and close braces -may be used instead of +are dropped. +Note that any unquoted space before and after a pattern is +stripped; any space with a pattern must be quoted. +Both the word and the +patterns are subject to parameter, command, and arithmetic substitution, as +well as tilde substitution. +For historical reasons, open and close braces may be used instead of .Ic in and .Ic esac @@ -540,11 +562,12 @@ in the specified word list, the parameter .Ar name is set to the word and .Ar list -is executed. If +is executed. +If .Ic in is not used to specify a word list, the positional parameters ($1, $2, etc.) -are used instead. For historical reasons, open and close braces may be used -instead of +are used instead. +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -573,8 +596,8 @@ is executed; otherwise, the .Ar list following the .Ic elif , -if any, is executed with similar consequences. If all the lists following -the +if any, is executed with similar consequences. +If all the lists following the .Ic if and .Ic elif Ns s @@ -582,7 +605,8 @@ fail (i.e., exit with non-zero status), the .Ar list following the .Ic else -is executed. The exit status of an +is executed. +The exit status of an .Ic if statement is that of non-conditional .Ar list @@ -596,7 +620,8 @@ is executed, the exit status is zero. The .Ic select statement provides an automatic method of presenting the user with a menu and -selecting from it. An enumerated list of the specified +selecting from it. +An enumerated list of the specified .Ar word Ns s is printed on standard error, followed by a prompt .Po @@ -621,13 +646,15 @@ completes, the enumerated list is printed if .Ev REPLY is .Dv NULL , -the prompt is printed and so on. This process continues until an end-of-file +the prompt is printed and so on. +This process continues until an end-of-file is read, an interrupt is received, or a .Ic break -statement is executed inside the loop. If +statement is executed inside the loop. +If .Ic in Ar word Ar ... -is omitted, the positional parameters are used (i.e., $1, $2, etc.). For -historical reasons, open and close braces may be used instead of +is omitted, the positional parameters are used (i.e., $1, $2, etc.). +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -651,10 +678,11 @@ is non-zero. .Xc A .Ic while -is a pre-checked loop. Its body is executed as often as the exit status of -the first +is a pre-checked loop. +Its body is executed as often as the exit status of the first .Ar list -is zero. The exit status of a +is zero. +The exit status of a .Ic while statement is the last exit status of the .Ar list @@ -666,7 +694,8 @@ Defines the function .Ar name (see .Sx Functions -below). Note that redirections specified after a function definition are +below). +Note that redirections specified after a function definition are performed whenever the function is executed, not when the function definition is executed. .It Ar name Ic () Ar command @@ -750,7 +779,8 @@ are evaluated and lazy expression evaluation is used for the .Ql && and .Ql || -operators. This means that in the statement +operators. +This means that in the statement .Pp .Ic \&[[ -r foo && $(< foo) = b*r ]] .Pp @@ -763,15 +793,18 @@ exists and is readable. .El .Ss Quoting Quoting is used to prevent the shell from treating characters or words -specially. There are three methods of quoting. First, +specially. +There are three methods of quoting. +First, .Ql \e quotes the following character, unless it is at the end of a line, in which case both the .Ql \e -and the newline are stripped. Second, a single quote +and the newline are stripped. +Second, a single quote .Pq Sq ' -quotes everything up to the next single quote (this may span lines). Third, -a double quote +quotes everything up to the next single quote (this may span lines). +Third, a double quote .Pq Sq \&" quotes all characters, except .Ql $ , @@ -784,7 +817,8 @@ and .Ql ` inside double quotes have their usual meaning (i.e., parameter, command or arithmetic substitution) except no field splitting is carried out on the -results of double-quoted substitutions. If a +results of double-quoted substitutions. +If a .Ql \e inside a double-quoted string is followed by .Ql \e , @@ -807,13 +841,15 @@ below for a special rule regarding sequences of the form .Ss Aliases There are two types of aliases: normal command aliases and tracked aliases. Command aliases are normally used as a short hand for a long or often used -command. The shell expands command aliases (i.e., substitutes the alias name -for its value) when it reads the first word of a command. An expanded alias -is re-processed to check for more aliases. If a command alias ends in a -space or tab, the following word is also checked for alias expansion. The -alias expansion process stops when a word that is not an alias is found, when -a quoted word is found or when an alias word that is currently being expanded -is found. +command. +The shell expands command aliases (i.e., substitutes the alias name +for its value) when it reads the first word of a command. +An expanded alias is re-processed to check for more aliases. +If a command alias ends in a +space or tab, the following word is also checked for alias expansion. +The alias expansion process stops when a word that is not an alias is found, +when a quoted word is found or when an alias word that is currently being +expanded is found. .Pp The following command aliases are defined automatically by the shell: .Pp @@ -847,22 +883,27 @@ The following command aliases are defined automatically by the shell: .El .Pp Tracked aliases allow the shell to remember where it found a particular -command. The first time the shell does a path search for a command that is -marked as a tracked alias, it saves the full path of the command. The next +command. +The first time the shell does a path search for a command that is +marked as a tracked alias, it saves the full path of the command. +The next time the command is executed, the shell checks the saved path to see that it -is still valid, and if so, avoids repeating the path search. Tracked aliases -can be listed and created using +is still valid, and if so, avoids repeating the path search. +Tracked aliases can be listed and created using .Ic alias -t . Note that changing the .Ev PATH -parameter clears the saved paths for all tracked aliases. If the +parameter clears the saved paths for all tracked aliases. +If the .Ic trackall option is set (i.e., .Ic set Fl o Ic trackall or .Ic set Fl h ) , -the shell tracks all commands. This option is set automatically for -non-interactive shells. For interactive shells, only the following commands are +the shell tracks all commands. +This option is set automatically for +non-interactive shells. +For interactive shells, only the following commands are automatically tracked: .Ic cat , cc , chmod , cp , .Ic date , ed , emacs , grep , @@ -873,8 +914,10 @@ and .Ic who . .Ss Substitution The first step the shell takes in executing a simple-command is to perform -substitutions on the words of the command. There are three kinds of -substitution: parameter, command, and arithmetic. Parameter substitutions, +substitutions on the words of the command. +There are three kinds of +substitution: parameter, command, and arithmetic. +Parameter substitutions, which are described in detail in the next section, take the form .Ic $ Ns Ar name or @@ -890,7 +933,8 @@ If a substitution appears outside of double quotes, the results of the substitution are generally subject to word or field splitting according to the current value of the .Ev IFS -parameter. The +parameter. +The .Ev IFS parameter specifies a list of characters which are used to break a string up into several words; any characters from the set space, tab, and newline that @@ -903,7 +947,8 @@ Sequences of one or more whitespace characters, in combination with zero or no .Pf non- Ev IFS whitespace -characters, delimit a field. As a special case, leading and trailing +characters, delimit a field. +As a special case, leading and trailing .Ev IFS whitespace is stripped (i.e., no leading or trailing empty field is created by it); leading or trailing @@ -932,7 +977,8 @@ The results of substitution are, unless otherwise specified, also subject to brace expansion and file name expansion (see the relevant sections below). .Pp A command substitution is replaced by the output generated by the specified -command, which is run in a subshell. For +command, which is run in a subshell. +For .Ic $( Ns Ar command Ns Ic \&) substitutions, normal quoting rules are used when .Ar command @@ -947,8 +993,8 @@ or .Ql \e is stripped (a .Ql \e -followed by any other character is unchanged). As a special case in command -substitutions, a command of the form +followed by any other character is unchanged). +As a special case in command substitutions, a command of the form .Ic \&< Ar file is interpreted to mean substitute the contents of .Ar file @@ -961,17 +1007,20 @@ but it is carried out more efficiently because no process is started). .Sy Note: .Ic $( Ns Ar command Ns Ic \&) expressions are currently parsed by finding the matching parenthesis, -regardless of quoting. This should be fixed soon. +regardless of quoting. +This should be fixed soon. .Pp Arithmetic substitutions are replaced by the value of the specified expression. For example, the command .Ic echo $((2+3*4)) -prints 14. See +prints 14. +See .Sx Arithmetic expressions for a description of an expression. .Ss Parameters Parameters are shell variables; they can be assigned values and their values -can be accessed using a parameter substitution. A parameter name is either one +can be accessed using a parameter substitution. +A parameter name is either one of the special single punctuation or digit character parameters described below, or a letter followed by zero or more letters or digits .Po @@ -1006,12 +1055,12 @@ or .Pc is set, in which case an error occurs. .Pp -Parameters can be assigned valued in a number of ways. First, the shell -implicitly sets some parameters like +Parameters can be assigned valued in a number of ways. +First, the shell implicitly sets some parameters like .Ic # , PWD , etc.; this is the only way the special single character parameters are set. -Second, parameters are imported from the shell's environment at startup. Third, -parameters can be assigned values on the command line, for example, +Second, parameters are imported from the shell's environment at startup. +Third, parameters can be assigned values on the command line, for example, .Ic FOO=bar sets the parameter .Ev FOO @@ -1020,18 +1069,19 @@ to multiple parameter assignments can be given on a single command line and they can be followed by a simple-command, in which case the assignments are in effect only for the duration of the command (such assignments are also -exported, see below for implications of this). Note that both the parameter -name and the +exported, see below for implications of this). +Note that both the parameter name and the .Ql = -must be unquoted for the shell to recognize a parameter assignment. The fourth -way of setting a parameter is with the +must be unquoted for the shell to recognize a parameter assignment. +The fourth way of setting a parameter is with the .Ic export , .Ic readonly and .Ic typeset commands; see their descriptions in the .Sx Command execution -section. Fifth, +section. +Fifth, .Ic for and .Ic select @@ -1040,7 +1090,8 @@ loops set parameters as well as the .Ic read and .Ic set Fl A -commands. Lastly, parameters can be assigned values using assignment operators +commands. +Lastly, parameters can be assigned values using assignment operators inside arithmetic expressions (see .Sx Arithmetic expressions below) or using the @@ -1058,8 +1109,10 @@ the environment (see .Xr environ 5 ) of commands run by the shell as .Ar name Ns No = Ns Ar value -pairs. The order in which parameters appear in the environment of a command is -unspecified. When the shell starts up, it extracts parameters and their values +pairs. +The order in which parameters appear in the environment of a command is +unspecified. +When the shell starts up, it extracts parameters and their values from its environment and automatically sets the export attribute for those parameters. .Pp @@ -1110,7 +1163,8 @@ it is substituted; otherwise, is printed on standard error (preceded by .Ar name Ns No \&: ) and an error occurs (normally causing termination of a shell script, function -or .-script). If word is omitted the string +or .-script). +If word is omitted the string .Dq parameter null or not set is used instead. .El @@ -1156,7 +1210,8 @@ If .Ar pattern matches the beginning of the value of parameter .Ar name , -the matched text is deleted from the result of substitution. A single +the matched text is deleted from the result of substitution. +A single .Ql # results in the shortest match, and two of them result in the longest match. @@ -1178,8 +1233,8 @@ The following special parameters are implicitly set by the shell and cannot be set directly using assignments: .Bl -tag -width "1 ... 9" .It Ev \&! -Process ID of the last background process started. If no background processes -have been started, the parameter is not set. +Process ID of the last background process started. +If no background processes have been started, the parameter is not set. .It Ev \&# The number of positional parameters (i.e., $1, $2, etc.). .It Ev \&$ @@ -1192,8 +1247,8 @@ The concatenation of the current single letter options (see .Ic set command below for list of options). .It Ev \&? -The exit status of the last non-asynchronous command executed. If the last -command was killed by a signal, +The exit status of the last non-asynchronous command executed. +If the last command was killed by a signal, .Ic \&$\&? is set to 128 plus the signal number. .It Ev 0 @@ -1207,17 +1262,20 @@ option and the .Ar command-name was supplied, or the .Ar file -argument, if it was supplied. If the +argument, if it was supplied. +If the .Ic posix option is not set, .Ic \&$0 is the name of the current function or script. .It Ev 1 ... Ev 9 The first nine positional parameters that were supplied to the shell, function -or .-script. Further positional parameters may be accessed using +or .-script. +Further positional parameters may be accessed using .Ic ${ Ns Ar number Ns Ic \&} . .It Ev \&* -All positional parameters (except parameter 0), i.e., $1, $2, $3... If used +All positional parameters (except parameter 0), i.e., $1, $2, $3... +If used outside of double quotes, parameters are separate words (which are subjected to word splitting); if used within double quotes, parameters are separated by the first character of the @@ -1230,8 +1288,8 @@ is Same as .Ic \&$\&* , unless it is used inside double quotes, in which case a separate word is -generated for each positional parameter. If there are no positional parameters, -no word is generated. +generated for each positional parameter. +If there are no positional parameters, no word is generated. .Ic \&$\&@ can be used to access arguments, verbatim, without losing .Dv NULL @@ -1242,9 +1300,10 @@ The following parameters are set and/or used by the shell: .Bl -tag -width "EXECSHELL" .It Ev \&_ No (underscore) When an external command is executed by the shell, this parameter is set in the -environment of the new process to the path of the executed command. In -interactive use, this parameter is also set in the parent shell to the last -word of the previous command. When +environment of the new process to the path of the executed command. +In interactive use, this parameter is also set in the parent shell to the last +word of the previous command. +When .Ev MAILPATH messages are evaluated, this parameter contains the name of the file that changed (see @@ -1253,27 +1312,31 @@ parameter below). .It Ev CDPATH Search path for the .Ic cd -built-in command. Works the same way as +built-in command. +Works the same way as .Ev PATH for those directories not beginning with .Ql / in .Ic cd -commands. Note that if +commands. +Note that if .Ev CDPATH is set and does not contain .Dq \&. -or contains an empty path, the current directory is not searched. Also, the +or contains an empty path, the current directory is not searched. +Also, the .Ic cd built-in command will display the resulting directory when a match is found in any search path other than the empty path. .It Ev COLUMNS -Set to the number of columns on the terminal or window. Currently set to the +Set to the number of columns on the terminal or window. +Currently set to the .Dq cols value as reported by .Xr stty 1 -if that value is non-zero. This parameter is used by the interactive line -editing modes, and by +if that value is non-zero. +This parameter is used by the interactive line editing modes, and by .Ic select , .Ic set Fl o , and @@ -1283,18 +1346,20 @@ commands to format information columns. If the .Ev VISUAL parameter is not set, this parameter controls the command-line editing mode for -interactive shells. See +interactive shells. +See .Ev VISUAL parameter below for how this works. .It Ev ENV If this parameter is found to be set after any profile files are executed, the -expanded value is used as a shell startup file. It typically contains function -and alias definitions. +expanded value is used as a shell startup file. +It typically contains function and alias definitions. .It Ev ERRNO Integer value of the shell's .Va errno -variable. It indicates the reason the last system call failed. Not yet -implemented. +variable. +It indicates the reason the last system call failed. +Not yet implemented. .It Ev EXECSHELL If set, this parameter is assumed to contain the shell that is to be used to execute commands that @@ -1310,14 +1375,16 @@ command (see below). Like .Ev PATH , but used when an undefined function is executed to locate the file defining the -function. It is also searched when a command can't be found using +function. +It is also searched when a command can't be found using .Ev PATH . See .Sx Functions below for more information. .It Ev HISTFILE -The name of the file used to store command history. When assigned to, history -is loaded from the specified file. Also, several invocations of the shell +The name of the file used to store command history. +When assigned to, history is loaded from the specified file. +Also, several invocations of the shell running on the same machine will share history if their .Ev HISTFILE parameters all point to the same file. @@ -1325,14 +1392,15 @@ parameters all point to the same file. .Sy Note: If .Ev HISTFILE -isn't set, no history file is used. This is different from the original Korn -shell, which uses +isn't set, no history file is used. +This is different from the original Korn shell, which uses .Pa $HOME/.sh_history ; in future, .Nm pdksh may also use a default history file. .It Ev HISTSIZE -The number of commands normally stored for history. The default is 128. +The number of commands normally stored for history. +The default is 128. .It Ev HOME The default directory for the .Ic cd @@ -1345,7 +1413,8 @@ below). Internal field separator, used during substitution and by the .Ic read command, to split values into distinct arguments; normally set to space, tab -and newline. See +and newline. +See .Sx Substitution above for details. .Pp @@ -1363,7 +1432,8 @@ sections, below. The line number of the function or shell script that is currently being executed. .It Ev LINES -Set to the number of lines on the terminal or window. Not yet implemented. +Set to the number of lines on the terminal or window. +Not yet implemented. .It Ev MAIL If set, the user will be informed of the arrival of mail in the named file. This parameter is ignored if the @@ -1375,20 +1445,23 @@ by .Ev MAIL or .Ev MAILPATH . -If set to 0, the shell checks before each prompt. The default is 600 (10 -minutes). +If set to 0, the shell checks before each prompt. +The default is 600 (10 minutes). .It Ev MAILPATH -A list of files to be checked for mail. The list is colon separated, and each -file may be followed by a +A list of files to be checked for mail. +The list is colon separated, and each file may be followed by a .Ql ? -and a message to be printed if new mail has arrived. Command, parameter and +and a message to be printed if new mail has arrived. +Command, parameter and arithmetic substitution is performed on the message, and, during substitution, the parameter .Ev $_ -contains the name of the file. The default message is +contains the name of the file. +The default message is .Dq you have mail in $_ . .It Ev OLDPWD -The previous working directory. Unset if +The previous working directory. +Unset if .Ic cd has not successfully changed directories since the shell started, or if the shell doesn't know where it is. @@ -1404,25 +1477,29 @@ Assigning 1 to this parameter causes to process arguments from the beginning the next time it is invoked. .It Ev PATH A colon separated list of directories that are searched when looking for -commands and .'d files. An empty string resulting from a leading or trailing +commands and .'d files. +An empty string resulting from a leading or trailing colon, or two adjacent colons, is treated as a .Dq \&. , the current directory. .It Ev POSIXLY_CORRECT If set, this parameter causes the .Ic posix -option to be enabled. See +option to be enabled. +See .Sx POSIX mode below. .It Ev PPID The process ID of the shell's parent (read-only). .It Ev PS1 -The primary prompt for interactive shells. Parameter, command, and arithmetic +The primary prompt for interactive shells. +Parameter, command, and arithmetic substitutions are performed, and .Ql ! is replaced with the current command number (see .Ic fc -command below). A literal +command below). +A literal .Ql ! can be put in the prompt by placing .Ql !! @@ -1430,11 +1507,13 @@ in .Ev PS1 . Note that since the command-line editors try to figure out how long the prompt is (so they know how far it is to the edge of the screen), escape codes in -the prompt tend to mess things up. You can tell the shell not to count certain +the prompt tend to mess things up. +You can tell the shell not to count certain sequences (such as escape codes) by prefixing your prompt with a non-printing character (such as control-A) followed by a carriage return and then delimiting -the escape codes with this non-printing character. If you don't have any -non-printing characters, you're out of luck. By the way, don't blame me for +the escape codes with this non-printing character. +If you don't have any non-printing characters, you're out of luck. +By the way, don't blame me for this hack; it's in the original .Xr ksh . Default is @@ -1449,30 +1528,36 @@ used when more input is needed to complete a command. .It Ev PS3 Prompt used by .Ic select -statement when reading a menu selection. Default is +statement when reading a menu selection. +Default is .Dq \&#\&?\ \& . .It Ev PS4 Used to prefix commands that are printed during execution tracing (see .Ic set Fl x -command below). Parameter, command, and arithmetic substitutions are performed -before it is printed. Default is +command below). +Parameter, command, and arithmetic substitutions are performed +before it is printed. +Default is .Dq \&+\ \& . .It Ev PWD -The current working directory. May be unset or +The current working directory. +May be unset or .Dv NULL if the shell doesn't know where it is. .It Ev RANDOM -A simple random number generator. Every time +A simple random number generator. +Every time .Ev RANDOM -is referenced, it is assigned the next number in a random number series. The -point in the series can be set by assigning a number to +is referenced, it is assigned the next number in a random number series. +The point in the series can be set by assigning a number to .Ev RANDOM (see .Xr rand 3 ) . .It Ev REPLY Default parameter for the .Ic read -command if no names are given. Also used in +command if no names are given. +Also used in .Ic select loops to store the value that is read from standard input. .It Ev SECONDS @@ -1486,13 +1571,15 @@ prompt .Pq Ev PS1 . If the time is exceeded, the shell exits. .It Ev TMPDIR -The directory shell temporary files are created in. If this parameter is not +The directory shell temporary files are created in. +If this parameter is not set, or does not contain the absolute path of a writable directory, temporary files are created in .Pa /tmp . .It Ev VISUAL If set, this parameter controls the command-line editing mode for interactive -shells. If the last component of the path specified in this parameter contains +shells. +If the last component of the path specified in this parameter contains the string .Dq vi , .Dq emacs @@ -1511,7 +1598,8 @@ on words starting with an unquoted .Ql ~ . The characters following the tilde, up to the first .Ql / , -if any, are assumed to be a login name. If the login name is empty, +if any, are assumed to be a login name. +If the login name is empty, .Ql + or .Ql - , @@ -1520,9 +1608,11 @@ the value of the .Ev PWD , or .Ev OLDPWD -parameter is substituted, respectively. Otherwise, the password file is +parameter is substituted, respectively. +Otherwise, the password file is searched for the login name, and the tilde expression is substituted with the -user's home directory. If the login name is not found in the password file or +user's home directory. +If the login name is not found in the password file or if any quoting or parameter substitution occurs in the login name, no substitution is performed. .Pp @@ -1564,13 +1654,15 @@ expands to four words: and .Dq ade ) . As noted in the example, brace expressions can be nested and the resulting -words are not sorted. Brace expressions must contain an unquoted comma +words are not sorted. +Brace expressions must contain an unquoted comma .Pq Sq \&, for expansion to occur (i.e., .Ic {} and .Ic {foo} -are not expanded). Brace expansion is carried out after parameter substitution +are not expanded). +Brace expansion is carried out after parameter substitution and before file name generation. .Ss File name patterns A file name pattern is a word containing one or more unquoted @@ -1579,30 +1671,34 @@ or .Ql * characters or .Dq [..] -sequences. Once brace expansion has been performed, the shell replaces file +sequences. +Once brace expansion has been performed, the shell replaces file name patterns with the sorted named of all the files that match the pattern -(if no files match, the word is left unchanged). The pattern elements have the -following meaning: +(if no files match, the word is left unchanged). +The pattern elements have the following meaning: .Bl -tag -width Ds .It Ic \&? Matches any single character. .It Ic \&* Matches any sequence of characters. .It Ic \&[ Ns No .. Ns Ic \&] -Matches any of the characters inside the brackets. Ranges of characters can be +Matches any of the characters inside the brackets. +Ranges of characters can be specified by separating two characters by a .Ql - (e.g., .Dq [a0-9] matches the letter .Dq a -or any digit). In order to represent itself, a +or any digit). +In order to represent itself, a .Ql - must either be quoted or the first or last character in the character list. Similarly, a .Ql \&] must be quoted or the first character in the list if it is to represent itself -instead of the end of the list. Also, a +instead of the end of the list. +Also, a .Ql ! appearing at the start of the list has special meaning (see below), so to represent itself it must be quoted or appear later in the list. @@ -1616,7 +1712,8 @@ except it matches any character not inside the brackets. .Xc .Sm on Matches any string of characters that matches zero or more occurrences of the -specified patterns. Example: The pattern +specified patterns. +Example: The pattern .Ic \&*(foo\&|bar) matches the strings .Dq , @@ -1630,7 +1727,8 @@ etc. .Xc .Sm on Matches any string of characters that matches one or more occurrences of the -specified patterns. Example: The pattern +specified patterns. +Example: The pattern .Ic \&+(foo\&|bar) matches the strings .Dq foo , @@ -1643,7 +1741,8 @@ etc. .Xc .Sm on Matches the empty string or a string that matches one of the specified -patterns. Example: The pattern +patterns. +Example: The pattern .Ic \&?(foo\&|bar) only matches the strings .Dq , @@ -1655,8 +1754,8 @@ and .Ic \&| Ar pattern Ic \&) .Xc .Sm on -Matches a string that matches one of the specified patterns. Example: The -pattern +Matches a string that matches one of the specified patterns. +Example: The pattern .Ic \&@(foo\&|bar) only matches the strings .Dq foo @@ -1667,8 +1766,8 @@ and .Ic \&| Ar pattern Ic \&) .Xc .Sm on -Matches any string that does not match one of the specified patterns. Examples: -The pattern +Matches any string that does not match one of the specified patterns. +Examples: The pattern .Ic \&!(foo\&|bar) matches all strings except .Dq foo @@ -1724,7 +1823,8 @@ expression) are not yet implemented. .Ss Input/output redirection When a command is executed, its standard input, standard output, and standard error (file descriptors 0, 1, and 2, respectively) are normally inherited from -the shell. Three exceptions to this are commands in pipelines, for which +the shell. +Three exceptions to this are commands in pipelines, for which standard input and/or standard output are those set up by the pipeline, asynchronous commands created when job control is disabled, for which standard input is initially set to be from @@ -1738,8 +1838,8 @@ If .Ar file does not exist, it is created; if it does exist, is a regular file and the .Ic noclobber -option is set, an error occurs; otherwise, the file is truncated. Note that -this means the command +option is set, an error occurs; otherwise, the file is truncated. +Note that this means the command .Ic cmd < foo > foo will open .Ar foo @@ -1758,7 +1858,8 @@ Same as .Ic \&> , except if .Ar file -exists it is appended to instead of being truncated. Also, the file is opened +exists it is appended to instead of being truncated. +Also, the file is opened in append mode, so writes always go to the end of the file (see .Fn open 2 ) . .It Ic \&< Ar file @@ -1775,8 +1876,10 @@ After reading the command line containing this kind of redirection (called a the shell copies lines from the command source into a temporary file until a line matching .Ar marker -is read. When the command is executed, standard input is redirected from the -temporary file. If +is read. +When the command is executed, standard input is redirected from the +temporary file. +If .Ar marker contains no quoted characters, the contents of the temporary file are processed as if enclosed in double quotes each time the command is executed, so @@ -1814,16 +1917,19 @@ except the operation is done on standard output. .Pp In any of the above redirections, the file descriptor that is redirected (i.e., standard input or standard output) can be explicitly given by preceding the -redirection with a single digit. Parameter, command, and arithmetic +redirection with a single digit. +Parameter, command, and arithmetic substitutions, tilde substitutions, and (if the shell is interactive) file name generation are all performed on the .Ar file , .Ar marker and .Ar fd -arguments of redirections. Note, however, that the results of any file name +arguments of redirections. +Note, however, that the results of any file name generation are only used if a single file is matched; if multiple files match, -the word with the expanded file name generation characters is used. Note +the word with the expanded file name generation characters is used. +Note that in restricted shells, redirections which can create files cannot be used. .Pp For simple-commands, redirections may appear anywhere in the command; for @@ -1832,7 +1938,8 @@ compound-commands .Ic if statements, etc. .Pc , -any redirections must appear at the end. Redirections are processed after +any redirections must appear at the end. +Redirections are processed after pipelines are created and in the order they are given, so .Pp .Ic cat /foo/bar 2\&>&1 \&> /dev/null \&| cat -n @@ -1927,7 +2034,8 @@ Arithmetic (bit-wise) .Tn NOT . .It Ic \&+\&+ Increment; must be applied to a parameter (not a literal or other expression). -The parameter is incremented by 1. When used as a prefix operator, the result +The parameter is incremented by 1. +When used as a prefix operator, the result is the incremented value of the parameter; when used as a postfix operator, the result is the original value of the parameter. .It Ic \&-\&- @@ -1936,8 +2044,8 @@ Similar to except the parameter is decremented by 1. .It Ic \&, Separates two arithmetic expressions; the left-hand side is evaluated first, -then the right. The result is the value of the expression on the right-hand -side. +then the right. +The result is the value of the expression on the right-hand side. .It Ic = Assignment; variable on the left is set to the value on the right. .It Xo Ic \&*= /= \&+= \&-= \&<\&<= @@ -1957,13 +2065,13 @@ is the same as .It Ic \&|\&| Logical .Tn OR ; -the result is 1 if either argument is non-zero, 0 if not. The right -argument is evaluated only if the left argument is zero. +the result is 1 if either argument is non-zero, 0 if not. +The right argument is evaluated only if the left argument is zero. .It Ic \&&\&& Logical .Tn AND ; -the result is 1 if both arguments are non-zero, 0 if not. The -right argument is evaluated only if the left argument is non-zero. +the result is 1 if both arguments are non-zero, 0 if not. +The right argument is evaluated only if the left argument is non-zero. .It Ic \&| Arithmetic (bit-wise) .Tn OR . @@ -1982,7 +2090,8 @@ Not equal; the result is 0 if both arguments are equal, 1 if not. Less than; the result is 1 if the left argument is less than the right, 0 if not. .It Ic \&<= \&>= \&> -Less than or equal, greater than or equal, greater than. See +Less than or equal, greater than or equal, greater than. +See .Ic \&< . .It Ic \&<\&< \&>\&> Shift left (right); the result is the left argument with its bits shifted left @@ -1991,8 +2100,8 @@ Shift left (right); the result is the left argument with its bits shifted left Addition, subtraction, multiplication, and division. .It Ic % Remainder; the result is the remainder of the division of the left argument by -the right. The sign of the result is unspecified if either argument is -negative. +the right. +The sign of the result is unspecified if either argument is negative. .It Xo Ao Ar arg1 Ac Ic \ \&? .Ao Ar arg2 Ac Ic \ \&: Ao Ar arg3 Ac .Xc @@ -2014,11 +2123,13 @@ The input and output of the co-process can also be manipulated using .Ic \&>\&&p and .Ic \&<\&&p -redirections, respectively. Once a co-process has been started, another can't +redirections, respectively. +Once a co-process has been started, another can't be started until the co-process exits, or until the co-process's input has been redirected using an .Ic exec Ar n Ns Ic \&>\&&p -redirection. If a co-process's input is redirected in this way, the next +redirection. +If a co-process's input is redirected in this way, the next co-process to be started will share the output with the first co-process, unless the output of the initial co-process has been redirected using an .Ic exec Ar n Ns Ic \&<\&&p @@ -2033,11 +2144,14 @@ close that file descriptor (e.g., .Ic exec 3\&>\&&p\&; exec 3>\&>\&&\&- ) . .It In order for co-processes to share a common output, the shell must keep the -write portion of the output pipe open. This means that end-of-file will not be +write portion of the output pipe open. +This means that end-of-file will not be detected until all co-processes sharing the co-process output have exited -(when they all exit, the shell closes its copy of the pipe). This can be +(when they all exit, the shell closes its copy of the pipe). +This can be avoided by redirecting the output to a numbered file descriptor (as this also -causes the shell to close its copy). Note that this behaviour is slightly +causes the shell to close its copy). +Note that this behaviour is slightly different from the original Korn shell which closes its copy of the write portion of the co-process output when the most recently started co-process (instead of when all sharing co-processes) exits. @@ -2056,12 +2170,15 @@ Functions are defined using either Korn shell .Ic function Ar name syntax or the Bourne/POSIX shell .Fn name -syntax (see below for the difference between the two forms). Functions are like +syntax (see below for the difference between the two forms). +Functions are like .Li .-scripts -in that they are executed in the current environment. However, unlike +in that they are executed in the current environment. +However, unlike .Li .-scripts , shell arguments (i.e., positional parameters $1, $2, etc.) are never visible -inside them. When the shell is determining the location of a command, functions +inside them. +When the shell is determining the location of a command, functions are searched after special built-in commands, before regular and non-regular built-ins, and before the .Ev PATH @@ -2080,7 +2197,8 @@ may be used to create undefined functions; when an undefined function is executed, the shell searches the path specified in the .Ev FPATH parameter for a file with the same name as the function, which, if found, is -read and executed. If after executing the file the named function is found to +read and executed. +If after executing the file the named function is found to be defined, the function is executed; otherwise, the normal command search is continued (i.e., the shell searches the regular built-in command table and .Ev PATH ) . @@ -2098,24 +2216,28 @@ which can be set with .Ic typeset \&-ft and .Ic typeset \&-fx , -respectively. When a traced function is executed, the shell's +respectively. +When a traced function is executed, the shell's .Ic xtrace option is turned on for the function's duration; otherwise, the .Ic xtrace -option is turned off. The +option is turned off. +The .Dq export -attribute of functions is currently not used. In the original Korn shell, +attribute of functions is currently not used. +In the original Korn shell, exported functions are visible to shell scripts that are executed. .Pp Since functions are executed in the current shell environment, parameter assignments made inside functions are visible after the function completes. If this is not the desired effect, the .Ic typeset -command can be used inside a function to create a local parameter. Note that -special parameters (e.g., $$, $\&!) can't be scoped in this way. +command can be used inside a function to create a local parameter. +Note that special parameters (e.g., $$, $\&!) can't be scoped in this way. .Pp The exit status of a function is that of the last command executed in the -function. A function can be made to finish immediately using the +function. +A function can be made to finish immediately using the .Ic return command; this may also be used to explicitly specify the exit status. .Pp @@ -2143,12 +2265,13 @@ untouched, so using .Ic getopts inside a function interferes with using .Ic getopts -outside the function). In the future, the following differences will also be -added: +outside the function). +In the future, the following differences will also be added: .Bl -bullet -offset indent .It A separate trap/signal environment will be used during the execution of -functions. This will mean that traps set inside a function will not affect the +functions. +This will mean that traps set inside a function will not affect the shell's traps and signals that are not ignored in the shell (but may be trapped) will have their default effect in a function. .It @@ -2162,22 +2285,22 @@ The shell is intended to be compliant; however, in some cases, .Tn POSIX behaviour is contrary either to the original Korn shell behaviour or to user -convenience. How the shell behaves in these cases is determined by the state -of the +convenience. +How the shell behaves in these cases is determined by the state of the .Ic posix option .Pq Ic set Fl o Ic posix . If it is on, the .Tn POSIX -behaviour is followed; otherwise, it is not. The +behaviour is followed; otherwise, it is not. +The .Ic posix option is set automatically when the shell starts up if the environment contains the .Dv POSIXLY_CORRECT parameter. (The shell can also be compiled so that it is in .Tn POSIX -mode by -default; however, this is usually not desirable). +mode by default; however, this is usually not desirable). .Pp The following is a list of things that are affected by the state of the .Ic posix @@ -2188,15 +2311,16 @@ Occurrences of .Ic \e\&" inside double quoted .Ic `\&.\&.` -command substitutions. In +command substitutions. +In .Tn POSIX mode, the .Ic \e\&" is interpreted when the command is interpreted; in .Pf non- Tn POSIX mode, the -backslash is stripped before the command substitution is interpreted. For -example, +backslash is stripped before the command substitution is interpreted. +For example, .Ic echo \&"`echo \e\&"hi\e\&"`\&" produces .Dq \&"hi\&" @@ -2206,38 +2330,43 @@ mode, .Dq hi in .Pf non- Tn POSIX -mode. To avoid problems, use the +mode. +To avoid problems, use the .Ic $(...) form of command substitution. .It .Ic kill -l -output. In +output. +In .Tn POSIX mode, signal names are listed one per line; in .Pf non- Tn POSIX mode, -signal numbers, names and descriptions are printed in columns. In future, a new -option +signal numbers, names and descriptions are printed in columns. +In future, a new option .Po Fl v \ perhaps .Pc will be added to distinguish the two behaviours. .It .Ic fg -exit status. In +exit status. +In .Tn POSIX mode, the exit status is 0 if no errors occur; in .Pf non- Tn POSIX mode, the exit status is that of the last foregrounded job. .It .Ic eval -exit status. If +exit status. +If .Ic eval gets to see an empty command (i.e., .Ic eval "`false`" ) , its exit status in .Tn POSIX -mode will be 0. In +mode will be 0. +In .Pf non- Tn POSIX mode, it will be the exit status of the last command substitution that was done in the processing of the arguments to @@ -2256,12 +2385,14 @@ mode, options can start with either or .Ql + . .It -Brace expansion (also known as alternation). In +Brace expansion (also known as alternation). +In .Tn POSIX mode, brace expansion is disabled; in .Pf non- Tn POSIX -mode, brace expansion is enabled. Note that +mode, brace expansion is enabled. +Note that .Ic set Fl o Ic posix (or setting the .Ev POSIXLY_CORRECT @@ -2281,7 +2412,8 @@ options; in mode, it does. .It .Ic set -exit status. In +exit status. +In .Tn POSIX mode, the exit status of .Ic set @@ -2290,14 +2422,15 @@ is 0 if there are no errors; in mode, the exit status is that of any command substitutions performed in generating the .Ic set -command. For example, +command. +For example, .Ic set \&-\&- `false`; echo $? prints 0 in .Tn POSIX mode, 1 in .Pf non- Tn POSIX -mode. This construct is used in most -shell scripts that use the old +mode. +This construct is used in most shell scripts that use the old .Xr getopt 1 command. .It @@ -2307,7 +2440,8 @@ Argument expansion of .Ic readonly , and .Ic typeset -commands. In +commands. +In .Tn POSIX mode, normal argument expansion is done; in .Pf non- Tn POSIX @@ -2315,7 +2449,8 @@ mode, field splitting, file globbing, brace expansion, and (normal) tilde expansion are turned off, while assignment tilde expansion is turned on. .It -Signal specification. In +Signal specification. +In .Tn POSIX mode, signals can be specified as digits, only if signal numbers match @@ -2325,13 +2460,15 @@ KILL=9, ALRM=14, and TERM=15); in .Pf non- Tn POSIX mode, signals can always be digits. .It -Alias expansion. In +Alias expansion. +In .Tn POSIX mode, alias expansion is only carried out when reading command words; in .Pf non- Tn POSIX mode, alias expansion is carried out on any -word following an alias that ended in a space. For example, the following +word following an alias that ended in a space. +For example, the following .Ic for loop .Pp @@ -2352,7 +2489,8 @@ in .Pf non- Tn POSIX mode. .It -Test. In +Test. +In .Tn POSIX mode, the expression .Dq Fl t @@ -2360,8 +2498,7 @@ mode, the expression .Dq Ic \&! arguments) is always true as it is a non-zero length string; in .Pf non- Tn POSIX -mode, -it tests if file descriptor 1 is a tty (i.e., the +mode, it tests if file descriptor 1 is a tty (i.e., the .Ar fd argument to the .Fl t @@ -2369,28 +2506,29 @@ test may be left out and defaults to 1). .El .Ss Command execution After evaluation of command-line arguments, redirections and parameter -assignments, the type of command is determined: a special built-in, a +assignments, the type of command is determined: a special built-in, a function, a regular built-in, or the name of a file to execute found using the .Ev PATH -parameter. The checks are made in the above order. Special built-in commands -differ from other commands in that the +parameter. +The checks are made in the above order. +Special built-in commands differ from other commands in that the .Ev PATH parameter is not used to find them, and an error during their execution can cause a non-interactive shell to exit and parameter assignments that are -specified before the command are kept after the command completes. Just to -confuse things, if the +specified before the command are kept after the command completes. +Just to confuse things, if the .Ic posix option is turned off (see .Ic set command below), some special commands are very special in that no field splitting, file globbing, brace expansion, nor tilde expansion is performed -on arguments that look like assignments. Regular built-in commands are -different only in that the +on arguments that look like assignments. +Regular built-in commands are different only in that the .Ev PATH parameter is not used to find them. .Pp The original -.Nm +.Nm ksh and .Tn POSIX differ somewhat in which commands are considered @@ -2439,15 +2577,18 @@ The following described the special and regular built-in commands: .It Ic \&. Ar file Op Ar arg1 ... Execute the commands in .Ar file -in the current environment. The file is searched for in the directories of +in the current environment. +The file is searched for in the directories of .Ev PATH . If arguments are given, the positional parameters may be used to access them while .Ar file -is being executed. If no arguments are given, the positional parameters are +is being executed. +If no arguments are given, the positional parameters are those of the environment the command is used in. .It Ic \&: Op Ar ... -The null command. Exit status is set to zero. +The null command. +Exit status is set to zero. .It Xo Ic alias .Op Fl d | Ic +-t Op Fl r .Op Ic +-px @@ -2459,23 +2600,26 @@ The null command. Exit status is set to zero. .Xc Without arguments, .Ic alias -lists all aliases. For any name without a value, the existing alias is listed. +lists all aliases. +For any name without a value, the existing alias is listed. Any name with a value defines an alias (see .Sx Aliases above). .Pp -When listing aliases, one of two formats is used. Normally, aliases are listed -as +When listing aliases, one of two formats is used. +Normally, aliases are listed as .Ar name Ns No = Ar value , where .Ar value -is quoted. If options were preceded with +is quoted. +If options were preceded with .Ql + , or a lone .Ql + is given on the command line, only .Ar name -is printed. In addition, if the +is printed. +In addition, if the .Fl p option is used, each alias is prefixed with the string .Dq alias\ \& . @@ -2492,7 +2636,8 @@ with the export attribute (exporting an alias has no effect). The .Fl t option indicates that tracked aliases are to be listed/set (values specified on -the command line are ignored for tracked aliases). The +the command line are ignored for tracked aliases). +The .Fl r option indicates that all tracked aliases are to be reset. .Pp @@ -2503,11 +2648,11 @@ listed or set (see .Sx Tilde expansion above). .It Ic bg Op Ar job ... -Resume the specified stopped job(s) in the background. If no jobs are -specified, +Resume the specified stopped job(s) in the background. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic bind Op Fl m @@ -2545,7 +2690,8 @@ is set, it lists the search path for the directory containing .Ar dir . A .Dv NULL -path means the current directory. If +path means the current directory. +If .Ar dir is found in any component of the .Ev CDPATH @@ -2556,13 +2702,15 @@ If .Ar dir is missing, the home directory .Ev HOME -is used. If +is used. +If .Ar dir is .Dq - , the previous working directory is used (see .Ev OLDPWD -parameter). If the +parameter). +If the .Fl L option (logical path) is used or if the .Ic physical @@ -2572,13 +2720,15 @@ command below) isn't set, references to .Dq \&.\&. in .Ar dir -are relative to the path used to get to the directory. If the +are relative to the path used to get to the directory. +If the .Fl P option (physical path) is used or if the .Ic physical option is set, .Dq \&.\&. -is relative to the filesystem directory tree. The +is relative to the filesystem directory tree. +The .Ev PWD and .Ev OLDPWD @@ -2604,11 +2754,13 @@ options are given, .Ar cmd is executed exactly as if the .Ic command -had not been specified, with two exceptions. First, +had not been specified, with two exceptions. +First, .Ar cmd cannot be a shell function, and second, special built-in commands lose their specialness (i.e., redirection and utility errors do not cause the shell to -exit, and command assignments are not permanent). If the +exit, and command assignments are not permanent). +If the .Fl p option is given, a default search path is used instead of the current value of .Ev PATH @@ -2628,10 +2780,12 @@ For special and regular built-in commands and functions, their names are simply printed; for aliases, a command that defines them is printed; and for commands found by searching the .Ev PATH -parameter, the full path of the command is printed. If no command is found +parameter, the full path of the command is printed. +If no command is found (i.e., the path search fails), nothing is printed and .Ic command -exits with a non-zero status. The +exits with a non-zero status. +The .Fl V option is like the .Fl v @@ -2652,7 +2806,8 @@ defaults to 1. .Op Ar arg ... .Xc Prints its arguments (separated by spaces) followed by a newline, to the -standard output. The newline is suppressed if any of the arguments contain the +standard output. +The newline is suppressed if any of the arguments contain the backslash sequence .Ql \ec . See the @@ -2661,7 +2816,8 @@ command below for a list of other backslash sequences that are recognized. .Pp The options are provided for compatibility with .Bx -shell scripts. The +shell scripts. +The .Fl n option suppresses the trailing newline, .Fl e @@ -2678,13 +2834,16 @@ The command is executed without forking, replacing the shell process. .Pp If no command is given except for I/O redirection, the I/O redirection is permanent and the shell is -not replaced. Any file descriptors greater than 2 which are opened or +not replaced. +Any file descriptors greater than 2 which are opened or .Xr dup 2 Ns 'd in this way are not made available to other executed commands (i.e., commands -that are not built-in to the shell). Note that the Bourne shell differs here; +that are not built-in to the shell). +Note that the Bourne shell differs here; it does pass these file descriptors on. .It Ic exit Op Ar status -The shell exits with the specified exit status. If +The shell exits with the specified exit status. +If .Ar status is not specified, the exit status is the current value of the .Ic \&? @@ -2692,9 +2851,9 @@ parameter. .It Xo Ic export Op Fl p .Op Ar parameter Ns Op \&= Ns Ar value .Xc -Sets the export attribute of the named parameters. Exported parameters are -passed in the environment to executed commands. If values are specified, the -named parameters are also assigned. +Sets the export attribute of the named parameters. +Exported parameters are passed in the environment to executed commands. +If values are specified, the named parameters are also assigned. .Pp If no parameters are specified, the names of all parameters with the export attribute are printed one per line, unless the @@ -2713,14 +2872,18 @@ A command that exits with a non-zero status. .Ar first and .Ar last -select commands from the history. Commands can be selected by history number -or a string specifying the most recent command starting with that string. The +select commands from the history. +Commands can be selected by history number +or a string specifying the most recent command starting with that string. +The .Fl l option lists the command on stdout, and .Fl n -inhibits the default command numbers. The +inhibits the default command numbers. +The .Fl r -option reverses the order of the list. Without +option reverses the order of the list. +Without .Fl l , the selected commands are edited by the editor specified with the .Fl e @@ -2751,10 +2914,11 @@ are replaced with This command is usually accessed with the predefined .Ic alias r='fx -e -' . .It Ic fg Op Ar job ... -Resume the specified job(s) in the foreground. If no jobs are specified, +Resume the specified job(s) in the foreground. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic getopts Ar optstring name @@ -2765,9 +2929,11 @@ parameters, if no arguments are given) and to check for legal options. .Ar optstring contains the option letters that .Ic getopts -is to recognize. If a letter is followed by a colon, the option is expected to -have an argument. Options that do not take arguments may be grouped in a single -argument. If an option takes an argument and the option character is not the +is to recognize. +If a letter is followed by a colon, the option is expected to +have an argument. +Options that do not take arguments may be grouped in a single argument. +If an option takes an argument and the option character is not the last character of the argument it is found in, the remainder of the argument is taken to be the option's argument; otherwise, the next argument is the option's argument. @@ -2793,14 +2959,15 @@ mark or a colon is placed in .Ar name (indicating an illegal option or missing argument, respectively) and .Ev OPTAG -is set to the option character that caused the problem. An error message is -also printed to standard error if +is set to the option character that caused the problem. +An error message is also printed to standard error if .Ar optstring does not being with a colon. .Pp When the end of the options is encountered, .Ic getopts -exits with a non-zero exit status. Options end at the first (non-option +exits with a non-zero exit status. +Options end at the first (non-option argument) argument that does not start with a .Ql - , or when a @@ -2821,9 +2988,11 @@ may lead to unexpected results. .It Xo Ic hash Op Fl r .Op Ar name ... .Xc -Without arguments, any hashed executable command pathnames are listed. The +Without arguments, any hashed executable command pathnames are listed. +The .Fl r -option causes all hashed commands to be removed from the hash table. Each +option causes all hashed commands to be removed from the hash table. +Each .Ar name is searched as if it were a command name and added to the hash table if it is an executable command. @@ -2831,14 +3000,18 @@ an executable command. .Op Ar job ... .Xc Display information about the specified job(s); if no jobs are specified, all -jobs are displayed. The +jobs are displayed. +The .Fl n option causes information to be displayed only for jobs that have changed -state since the last notification. If the +state since the last notification. +If the .Fl l -option is used, the process ID of each process in a job is also listed. The +option is used, the process ID of each process in a job is also listed. +The .Fl p -option causes only the process group of each job to be printed. See +option causes only the process group of each job to be printed. +See .Sx Job control below for the format of .Ar job @@ -2851,10 +3024,12 @@ and the displayed job. .Ar pgrp No } Ar ... .Xc Send the specified signal to the specified jobs, process IDs, or process -groups. If no signal is specified, the +groups. +If no signal is specified, the .Dv TERM -signal is sent. If a job is specified, the signal is sent to the job's -process group. See +signal is sent. +If a job is specified, the signal is sent to the job's process group. +See .Sx Job control below for the format of .Ar job . @@ -2867,8 +3042,10 @@ a short description of them are printed. .It Ic let Op Ar expression ... Each expression is evaluated (see .Sx Arithmetic expressions -above). If all expressions are successfully evaluated, the exit status is 0 (1) -if the last expression evaluated to non-zero (zero). If an error occurs during +above). +If all expressions are successfully evaluated, the exit status is 0 (1) +if the last expression evaluated to non-zero (zero). +If an error occurs during the parsing or evaluation of an expression, the exit status is greater than 1. Since expressions may need to be quoted, .Ic (( Ar expr Ic )) @@ -2881,9 +3058,11 @@ is syntactic sugar for .Xc .Ic print prints its arguments on the standard output, separated by spaces and -terminated with a newline. The +terminated with a newline. +The .Fl n -option suppresses the newline. By default, certain C escapes are translated. +option suppresses the newline. +By default, certain C escapes are translated. These include .Ql \eb , .Ql \ef , @@ -2904,7 +3083,8 @@ option. .Ql \e expansion may be inhibited with the .Fl r -option. The +option. +The .Fl s option prints to the history file instead of standard output, the .Fl u @@ -2929,11 +3109,13 @@ command, which does not process .Ql \e sequences unless the .Fl e -option is given. As above, the +option is given. +As above, the .Fl n option suppresses the trailing newline. .It Ic pwd Op Fl LP -Print the present working directory. If the +Print the present working directory. +If the .Fl L option is used or if the .Ic physical @@ -2941,7 +3123,8 @@ option (see .Ic set command below) isn't set, the logical path is printed (i.e., the path used to .Ic cd -to the current directory). If the +to the current directory). +If the .Fl P option (physical path) is used or if the .Ic physical @@ -2956,17 +3139,19 @@ using the .Ev IFS parameter (see .Sx Substitution -above), and assigns each field to the specified parameters. If there are more -parameters than fields, the extra parameters are set to +above), and assigns each field to the specified parameters. +If there are more parameters than fields, the extra parameters are set to .Dv NULL , or alternatively, if there are more fields than parameters, the last parameter -is assigned the remaining fields (inclusive of any separating spaces). If no -parameters are specified, the +is assigned the remaining fields (inclusive of any separating spaces). +If no parameters are specified, the .Ev REPLY -parameter is used. If the input line ends in a backslash and the +parameter is used. +If the input line ends in a backslash and the .Fl r option was not used, the backslash and the newline are stripped and more input -is read. If no input is read, +is read. +If no input is read, .Ic read exits with a non-zero status. .Pp @@ -2983,7 +3168,8 @@ options cause input to be read from file descriptor .Ar n or the current co-process (see .Sx Co-processes -above for comments on this), respectively. If the +above for comments on this), respectively. +If the .Fl s option is used, input is saved to the history file. .It Xo Ic readonly Op Fl p @@ -2991,8 +3177,10 @@ option is used, input is saved to the history file. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Sets the read-only attribute of the named parameters. If values are given, -parameters are set to them before setting the attribute. Once a parameter is +Sets the read-only attribute of the named parameters. +If values are given, +parameters are set to them before setting the attribute. +Once a parameter is made read-only, it cannot be unset and its value cannot be changed. .Pp If no parameters are specified, the names of all parameters with the read-only @@ -3009,8 +3197,8 @@ script, with exit status .Ar status . If no .Ar status -is given, the exit status of the last executed command is used. If used -outside of a function or +is given, the exit status of the last executed command is used. +If used outside of a function or .Ic \&. script, it has the same effect as .Ic exit . @@ -3062,7 +3250,8 @@ the rest are left untouched. All new parameters are created with the export attribute. .It Fl b Ic notify Print job notification messages asynchronously, instead of just before the -prompt. Only used if job control is enabled +prompt. +Only used if job control is enabled .Pq Fl m . .It Fl C Ic noclobber Prevent @@ -3076,7 +3265,8 @@ must be used to force an overwrite Exit (after executing the .Dv ERR trap) as soon as an error occurs or a command fails (i.e., exits with a -non-zero status). This does not apply to commands whose exit status is +non-zero status). +This does not apply to commands whose exit status is explicitly tested by a shell construct such as .Ic if , .Ic until , @@ -3090,34 +3280,40 @@ Do not expand file name patterns. .It Fl h Ic trackall Create tracked aliases for all executed commands (see .Sx Aliases -above). Enabled by default for non-interactive shells. +above). +Enabled by default for non-interactive shells. .It Fl i Ic interactive -Enable interactive mode. This can only be set/unset when the shell is invoked. +Enable interactive mode. +This can only be set/unset when the shell is invoked. .It Fl k Ic keyword Parameter assignments are recognized anywhere in a command. .It Fl l Ic login -The shell is a login shell. This can only be set/unset when the shell is +The shell is a login shell. +This can only be set/unset when the shell is invoked (see .Sx Shell startup above). .It Fl m Ic monitor Enable job control (default for interactive shells). .It Fl n lc noexec -Do not execute any commands. Useful for checking the syntax of scripts +Do not execute any commands. +Useful for checking the syntax of scripts (ignored if interactive). .It Fl p Ic privileged Set automatically if, when the shell starts, the read UID or GID does not match -the effective UID (EUID) or GID (EGID), respectively. See +the effective UID (EUID) or GID (EGID), respectively. +See .Sx Shell startup above for a description of what this means. .It Fl r Ic restricted -Enable restricted mode. This option can only be used when the shell is invoked. +Enable restricted mode. +This option can only be used when the shell is invoked. See .Sx Shell startup above for a description of what this means. .It Fl s Ic stdin -If used where the shell is invoked, commands are read from standard input. Set -automatically if the shell is invoked with no arguments. +If used where the shell is invoked, commands are read from standard input. +Set automatically if the shell is invoked with no arguments. .Pp When .Fl s @@ -3154,8 +3350,8 @@ Enable brace expansion (a.k.a., alternation). Enable BRL emacs-like command-line editing (interactive shells only); see .Sx Emacs editing mode. .It Ic gmacs -Enable gmacs-like command-line editing (interactive shells only). Currently -identical to emacs editing except that transpose (^T) acts slightly +Enable gmacs-like command-line editing (interactive shells only). +Currently identical to emacs editing except that transpose (^T) acts slightly differently. .It Ic ignoreeof The shell will not (easily) exit when end-of-file is read; @@ -3167,13 +3363,15 @@ is read 13 times in a row. .It Ic nohup Do not kill running jobs with a .Dv HUP -signal when a login shell exists. Currently set by default, but this will +signal when a login shell exists. +Currently set by default, but this will change in the future to be compatible with the original Korn shell (which doesn't have this option, but does send the .Dv HUP signal). .It Ic nolog -No effect. In the original Korn shell, this prevents function definitions from +No effect. +In the original Korn shell, this prevents function definitions from being stored in the history file. .It Ic physical Causes the @@ -3188,9 +3386,9 @@ directories instead of .Dq logical directories (i.e., the shell handles .Dq \&.\&. , -which allows the user to be oblivious of symbolic links to directories). Clear -by default. Note that setting this option does not affect the current value of -the +which allows the user to be oblivious of symbolic links to directories). +Clear by default. +Note that setting this option does not affect the current value of the .Ev PWD parameter; only the .Ic cd @@ -3204,13 +3402,15 @@ commands above for more details. .It Ic posix Enable .Tn POSIX -mode. See +mode. +See .Sx POSIX mode above. .It Ic vi Enable vi-like command-line editing (interactive shells only). .It Ic viraw -No effect. In the original Korn shell, unless +No effect. +In the original Korn shell, unless .Ic viraw was set, the vi command-line mode would let the tty driver do the work until .Tn ESC @@ -3227,10 +3427,12 @@ If this option is not set, characters in the range 128-160 are printed as is, which may cause problems. .It Ic vi-tabcomplete In vi command-line editing, do command and file name completion when tab (^I) -is entered in insert mode. This is the default. +is entered in insert mode. +This is the default. .El .Pp -These options can also be used upon invocation of the shell. The current set of +These options can also be used upon invocation of the shell. +The current set of options (with single letter names) can be found in the parameter .Dv \&- . .Ic set Fl o @@ -3239,11 +3441,12 @@ with no option name will list all the options and whether each is on or off; will print the long names of all options that are currently on. .Pp Remaining arguments, if any, are positional parameters and are assigned, in -order, to the positional parameters (i.e., $1, $2, etc.). If options end with +order, to the positional parameters (i.e., $1, $2, etc.). +If options end with .Ql -- -and there are no remaining arguments, all positional parameters are cleared. If -no options or arguments are given, the values of all names are printed. For -unknown historical reasons, a lone +and there are no remaining arguments, all positional parameters are cleared. +If no options or arguments are given, the values of all names are printed. +For unknown historical reasons, a lone .Ql - option is treated specially -- it clears both the .Fl x @@ -3266,15 +3469,18 @@ defaults to 1. evaluates the .Ar expression and returns zero status if true, 1 status if false, or greater than 1 if there -was an error. It is normally used as the condition command of +was an error. +It is normally used as the condition command of .Ic if and .Ic while -statements. The following basic expressions are available: +statements. +The following basic expressions are available: .Bl -tag -width 17n .It Ar str .Ar str -has non-zero length. Note that there is the potential for problems if +has non-zero length. +Note that there is the potential for problems if .Ar str turns out to be an operator (e.g., .Fl r ) . @@ -3350,8 +3556,8 @@ Shell .Ar option is set (see .Ic set -command above for a list of options). As a non-standard extension, if the -option starts with a +command above for a list of options). +As a non-standard extension, if the option starts with a .Ql ! , the test is negated; the test always fails if .Ar option @@ -3389,7 +3595,8 @@ is the same file as second .It Fl t Op Ar fd File descriptor .Ar fd -is a tty device. If the +is a tty device. +If the .Ic posix option is not set, .Ar fd @@ -3452,7 +3659,8 @@ is a file descriptor number), the .Ic test command will attempt to fake it for all tests that operate on files (except the .Fl e -test). For example, +test). +For example, .Ic \&[ -w /dev/fd/2 \&] tests if file descriptor 2 is writable. .Pp @@ -3495,7 +3703,8 @@ instead. .Xc If a .Ar pipeline -is given, the times used to execute the pipeline are reported. If no pipeline +is given, the times used to execute the pipeline are reported. +If no pipeline is given, then the user and system time used by the shell itself, and all the commands it has run since it was started, are reported. The times reported are the real time (elapsed time from start to finish), @@ -3515,7 +3724,8 @@ is a simple command), in which case the output is slightly longer: .Dl user 0.00 .Dl sys 0.00 .Pp -(the number of digits after the decimal may vary from system to system). Note +(the number of digits after the decimal may vary from system to system). +Note that simple redirections of standard error do not effect the output of the time command: .Pp @@ -3550,7 +3760,8 @@ or .Dv ALRM ) or the number of the signal (see .Ic kill -l -command above). There are two special signals: +command above). +There are two special signals: .Dv EXIT (also known as 0), which is executed when the shell is about to exit, and .Dv ERR , @@ -3563,7 +3774,8 @@ option were see -- see .Ic set command above). .Dv EXIT -handlers are executed in the environment of the last executed command. Note +handlers are executed in the environment of the last executed command. +Note that for non-interactive shells, the trap handler cannot be changed for signals that were ignored when the shell started. .Pp @@ -3598,7 +3810,8 @@ A command that exits with a zero value. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Display or set parameter attributes. With no +Display or set parameter attributes. +With no .Ar name arguments, parameter attributes are displayed; if no options are used, the current attributes of all parameters are printed as @@ -3616,7 +3829,8 @@ arguments are given, the attributes of the named parameters are set .Pq Ic \&- or cleared .Pq Ic \&+ . -Values for parameters may optionally be specified. If +Values for parameters may optionally be specified. +If .Ic typeset is used inside a function, any newly created parameters are local to the function. @@ -3625,7 +3839,8 @@ When .Fl f is used, .Ic typeset -operates on the attributes of functions. As with parameters, if no +operates on the attributes of functions. +As with parameters, if no .Ar name Ns s are given, functions are listed with their values (i.e., definitions) unless options are introduced with @@ -3635,24 +3850,31 @@ in which case only the function names are reported. .It Fl L Ns Ar n Left justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Leading whitespace (and zeros, if used with the +assigned value) is used. +Leading whitespace (and zeros, if used with the .Fl Z -option) is stripped. If necessary, values are either truncated or space padded +option) is stripped. +If necessary, values are either truncated or space padded to fit the field width. .It Fl R Ns Ar n Right justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Trailing whitespace is stripped. If necessary, values +assigned value) is used. +Trailing whitespace is stripped. +If necessary, values are either stripped of leading characters or space padded to make them fit the field width. .It Fl Z Ns Ar n -Zero fill attribute. If not combined with +Zero fill attribute. +If not combined with .Fl L , this is the same as .Fl R , @@ -3661,19 +3883,23 @@ except zero padding is used instead of space padding. Integer attribute. .Ar n specifies the base to use when displaying the integer (if not specified, the -base given in the first assignment is used). Parameters with this attribute may +base given in the first assignment is used). +Parameters with this attribute may be assigned values containing arithmetic expressions. .It Fl U -Unsigned integer attribute. Integers are printed as unsigned values (only +Unsigned integer attribute. +Integers are printed as unsigned values (only useful when combined with the .Fl i -option). This option is not in the original Korn shell. +option). +This option is not in the original Korn shell. .It Fl f -Function mode. Display or set functions and their attributes, instead of -parameters. +Function mode. +Display or set functions and their attributes, instead of parameters. .It Fl l -Lower case attribute. All upper case characters in values are converted to -lower case. (In the original Korn shell, this parameter meant +Lower case attribute. +All upper case characters in values are converted to lower case. +(In the original Korn shell, this parameter meant .Dq long integer when used with the .Fl i @@ -3682,52 +3908,63 @@ option.) Print complete .Ic typeset commands that can be used to re-create the attributes (but not the values) or -parameters. This is the default action (option exists for ksh93 compatibility). +parameters. +This is the default action (option exists for ksh93 compatibility). .It Fl r -Read-only attribute. Parameters with this attribute may not be assigned to or -unset. Once this attribute is set, it can not be turned off. +Read-only attribute. +Parameters with this attribute may not be assigned to or unset. +Once this attribute is set, it can not be turned off. .It Fl t -Tag attribute. Has no meaning to the shell; provided for application use. +Tag attribute. +Has no meaning to the shell; provided for application use. .Pp For functions, .Fl t -is the trace attribute. When functions with the trace attribute are executed, -the +is the trace attribute. +When functions with the trace attribute are executed, the .Ic xtrace .Pq Fl x shell option is temporarily turned on. .It Fl u -Upper case attribute. All lower case characters in values are converted to -upper case. (In the original Korn shell, this parameter meant +Upper case attribute. +All lower case characters in values are converted to upper case. +(In the original Korn shell, this parameter meant .Dq unsigned integer when used with the .Fl i option, which meant upper case letters would never be used for bases greater -than 10. See the +than 10. +See the .Fl U option.) .Pp For functions, .Fl u -is the undefined attribute. See +is the undefined attribute. +See .Sx Functions above for the implications of this. .It Fl x -Export attribute. Parameters (or functions) are placed in the environment of -any executed commands. Exported functions are not yet implemented. +Export attribute. +Parameters (or functions) are placed in the environment of +any executed commands. +Exported functions are not yet implemented. .El .It Xo Ic ulimit Op Fl acdfHlmnpsStvw .Op Ar value .Xc -Display or set process limits. If no options are used, the file size limit +Display or set process limits. +If no options are used, the file size limit .Pq Fl f is assumed. .Ar value , if specified, may be either an arithmetic expression or the word .Dq unlimited . The limits affect the shell and any processes created by the shell after a -limit is imposed. Note that some systems may not allow limits to be increased -once they are set. Also note that the types of limits available are system +limit is imposed. +Note that some systems may not allow limits to be increased +once they are set. +Also note that the types of limits available are system dependent -- some systems have only the .Fl f limit. @@ -3815,9 +4052,11 @@ and is equivalent (on most systems) to the octal mask .It Xo Ic unalias Op Fl adt .Op Ar name1 ... .Xc -The aliases for the given names are removed. If the +The aliases for the given names are removed. +If the .Fl a -option is used, all aliases are removed. If the +option is used, all aliases are removed. +If the .Fl t or .Fl d @@ -3836,7 +4075,8 @@ or functions The exit status is non-zero if any of the parameters were already unset, zero otherwise. .It Ic wait Op Ar job ... -Wait for the specified job(s) to finish. The exit status of +Wait for the specified job(s) to finish. +The exit status of .Ic wait is that of the last specified job; if the last job is killed by a signal, the exit status is 128 + the number of the signal (see @@ -3844,7 +4084,8 @@ exit status is 128 + the number of the signal (see above); if the last specified job can't be found (because it never existed, or had already finished), the exit status of .Ic wait -is 127. See +is 127. +See .Sx Job control below for the format of .Ar job . @@ -3859,7 +4100,8 @@ signal is received. If no jobs are specified, .Ic wait waits for all currently running jobs (if any) to finish and exits with a zero -status. If job monitoring is enabled, the completion status of jobs is printed +status. +If job monitoring is enabled, the completion status of jobs is printed (this is not the case when jobs are explicitly specified). .It Xo Ic whence Op Fl pv .Op Ar name ... @@ -3867,11 +4109,13 @@ status. If job monitoring is enabled, the completion status of jobs is printed For each .Ar name , the type of command is listed (reserved word, built-in, alias, -function, tracked alias, or executable). If the +function, tracked alias, or executable). +If the .Fl p option is used, a path search is performed even if .Ar name -is a reserved word, alias, etc. Without the +is a reserved word, alias, etc. +Without the .Fl v option, .Ic whence @@ -3879,7 +4123,8 @@ is similar to .Ic command Fl v except that .Ic whence -will find reserved words and won't print aliases as alias commands. With the +will find reserved words and won't print aliases as alias commands. +With the .Fl v option, .Ic whence @@ -3896,17 +4141,19 @@ status is non-zero. .El .Ss Job control Job control refers to the shell's ability to monitor and control jobs, which -are processes or groups of processes created for commands or pipelines. At a -minimum, the shell keeps track of the status of the background (i.e., +are processes or groups of processes created for commands or pipelines. +At a minimum, the shell keeps track of the status of the background (i.e., asynchronous) jobs that currently exist; this information can be displayed using the .Ic jobs -commands. If job control is fully enabled (using +commands. +If job control is fully enabled (using .Ic set Fl m or .Ic set Fl o Ic monitor ) , as it is for interactive shells, the processes of a job are placed in their -own process group. Foreground jobs can be stopped by typing the suspend +own process group. +Foreground jobs can be stopped by typing the suspend character from the terminal (normally ^Z), jobs can be restarted in either the foreground or background using the .Ic fg @@ -3921,11 +4168,12 @@ commands like .Ic read cannot be. .Pp -When a job is created, it is assigned a job number. For interactive shells, -this number is printed inside +When a job is created, it is assigned a job number. +For interactive shells, this number is printed inside .Dq \&[..\&] , followed by the process IDs of the processes in the job when an asynchronous -command is run. A job may be referred to in +command is run. +A job may be referred to in .Ic bg , .Ic fg , .Ic jobs , @@ -4000,12 +4248,14 @@ The job was stopped by the indicated .It Ar signal-description Op Dq core dumped The job was killed by a signal (e.g., memory fault, hangup, etc.; use .Ic kill -l -for a list of signal descriptions). The +for a list of signal descriptions). +The .Dq core dumped message indicates the process created a core file. .El .It Ar command -is the command that created the process. If there are multiple processes in +is the command that created the process. +If there are multiple processes in the job, each process will have a line showing its .Ar command and possibly its @@ -4018,10 +4268,12 @@ state, the shell warns the user that there are stopped jobs and does not exit. If another attempt is immediately made to exit the shell, the stopped jobs are sent a .Dv SIGHUP -signal and the shell exits. Similarly, if the +signal and the shell exits. +Similarly, if the .Ic nohup option is not set and there are running jobs when an attempt is made to exit -a login shell, the shell warns the user and does not exit. If another attempt +a login shell, the shell warns the user and does not exit. +If another attempt is immediately made to exit the shell, the running jobs are sent a .Dv SIGHUP signal and the shell exits. @@ -4060,11 +4312,14 @@ The line is scrolled horizontally as necessary. .Ss Emacs editing mode When the .Ic emacs -option is set, interactive input line editing is enabled. Warning: This mode is +option is set, interactive input line editing is enabled. +Warning: This mode is slightly different from the emacs mode in the original Korn shell and the 8th -bit is stripped in emacs mode. In this mode, various editing commands +bit is stripped in emacs mode. +In this mode, various editing commands (typically bound to one or more control characters) cause immediate actions -without waiting for a newline. Several editing commands are bound to particular +without waiting for a newline. +Several editing commands are bound to particular control characters when the shell is invoked; these binding can be changed using the following commands: .Bl -tag -width Ds @@ -4079,15 +4334,15 @@ which should consist of a control character (which may be written using caret notation, i.e., ^X), optionally preceded by one of the two prefix characters. Future input of the .Ar string -will cause the editing command to be immediately invoked. Note that although -only two prefix characters (usually +will cause the editing command to be immediately invoked. +Note that although only two prefix characters (usually .Tn ESC and ^X) are supported, some -multi-character sequences can be supported. The following binds the arrow keys -on an +multi-character sequences can be supported. +The following binds the arrow keys on an .Tn ANSI -terminal, or xterm (these are in the default bindings). Of course -some escape sequences won't work out quite this nicely. +terminal, or xterm (these are in the default bindings). +Of course some escape sequences won't work out quite this nicely. .Pp .Bl -item -compact .It @@ -4115,24 +4370,28 @@ will afterwards be immediately replaced by the given string, which may contain editing commands. .El .Pp -The following is a list of available editing commands. Each description starts -with the name of the command, an +The following is a list of available editing commands. +Each description starts with the name of the command, an .Ar n (if the command can be prefixed with a count), and any keys the command is bound to by default (written using caret notation, i.e., .Tn "ASCII ESC" character is -written as ^[). A count prefix for a command is entered using the sequence +written as ^[). +A count prefix for a command is entered using the sequence .Ic ^\&[ Ns Ar n , where .Ar n is a sequence of 1 or more digits; unless otherwise specified, if a count is -omitted, it defaults to 1. Note that editing command names are used only with -the +omitted, it defaults to 1. +Note that editing command names are used only with the .Ic bind -command. Furthermore, many editing commands are useful only on terminals with -a visible cursor. The default bindings were chosen to resemble corresponding -Emacs key bindings. The users' tty characters (e.g., +command. +Furthermore, many editing commands are useful only on terminals with +a visible cursor. +The default bindings were chosen to resemble corresponding +Emacs key bindings. +The users' tty characters (e.g., .Dv ERASE ) are bound to reasonable substitutes and override the default bindings. @@ -4142,8 +4401,8 @@ Useful as a response to a request for a .Ic search-history pattern in order to about the search. .It Ic auto-insert Ar n -Simply causes the character to appear as literal input. Most ordinary -characters are bound to this. +Simply causes the character to appear as literal input. +Most ordinary characters are bound to this. .It Ic backward-char Ar n Ic ^B Moves the cursor backward .Ar n @@ -4171,11 +4430,13 @@ is placed at the beginning of the line. .It Ic complete ^[^[ .It Ic complete ^I Automatically completes as much as is unique of the command name or the file -name containing the cursor. If the entire remaining command or file name is +name containing the cursor. +If the entire remaining command or file name is unique, a space is printed after its completion, unless it is a directory name in which case .Ql / -is appended. If there is no command or file name with the current partialword +is appended. +If there is no command or file name with the current partialword as its prefix, a bell character is output (usually causing a beep to be sounded). .It Ic complete-command ^X^[ @@ -4213,7 +4474,8 @@ words. .It Ic down-history Ar n Ic ^N Scrolls the history buffer forward .Ar n -lines (later). Each input line originally starts just after the last entry +lines (later). +Each input line originally starts just after the last entry in the history buffer, so .Ic down-history is not useful until either @@ -4245,7 +4507,8 @@ Places the cursor where the mark is and sets the mark to where the cursor was. Appends a .Ql * to the current word and replaces the word with the result of performing file -globbing on the word. If no files match the pattern, the bell is rung. +globbing on the word. +If no files match the pattern, the bell is rung. .It Ic forward-char Ar n Ic ^F Moves the cursor forward .Ar n @@ -4268,7 +4531,8 @@ is not specified; otherwise deletes characters between the cursor and column .Ar n . .It Ic list ^[? Prints a sorted, columnated list of command named or file names (if any) that -can complete the partial word containing the cursor. Directoary names have +can complete the partial word containing the cursor. +Directoary names have .Ql / appended to them. .It Ic list-command ^X? @@ -4276,16 +4540,17 @@ Prints a sorted, columnated list of command names (if any) that can complete the partial word containg the cursor. .It Ic list-file ^X^Y Prints a sorted, comunated list of file names (if any) that can complete the -partial word containing the cursor. File type indicators are appended as -described under +partial word containing the cursor. +File type indicators are appended as described under .Ic list above. .It Ic newline ^J , ^M -Causes the current input line to be processed by the shell. The current cursor -position may be anywhere on the line. +Causes the current input line to be processed by the shell. +The current cursor position may be anywhere on the line. .It Ic newline-and-next ^O Causes the current input line to be processed by the shell, and the next line -from history becomes the current line. This is only useful after an +from history becomes the current line. +This is only useful after an .Ic up-history or .ic search-history . @@ -4313,21 +4578,26 @@ Search forward in the current line for the .Ar n Ns th occurrence of the next character typed. .It Ic search-history ^R -Enter incremental search mode. The internal history list is searched -backwards for commands matching the input. An initial +Enter incremental search mode. +The internal history list is searched +backwards for commands matching the input. +An initial .Ql ^ -in the search string anchors the search. The abort key will leave search mode. -Other commands will be executed after leaving search mode. Successive +in the search string anchors the search. +The abort key will leave search mode. +Other commands will be executed after leaving search mode. +Successive .Ic search-history commands continue searching backward to the next previous occurrence of the -pattern. The history buffer retains only a finite number of lines; the oldest +pattern. +The history buffer retains only a finite number of lines; the oldest are discarded as necessary. .It Ic set-mark-command ^[ Ns No Set the mark at the cursor position. .It Ic stuff On systems supporting it, puhses the bound character back onto the terminal -input where it may receive special processing by the terminal handler. This -is useful for the BRL ^T mini-systat feature, for example. +input where it may receive special processing by the terminal handler. +This is useful for the BRL ^T mini-systat feature, for example. .It Ic stuff-reset Acts like .Ic stuff , @@ -4347,7 +4617,8 @@ Uppercase the next .Ar n words. .It Ic version ^V -Display the version of ksh. The current edit buffer is restored as soon as any +Display the version of ksh. +The current edit buffer is restored as soon as any key is pressed (the key is then processed, unless it is a space). .It Ic yank ^Y Inserts the most recently killed text string at the current cursor position. @@ -4399,28 +4670,34 @@ Like vi, there are two modes -- .Dq insert mode and .Dq command -mode. In insert mode, most characters are simply put in the buffer at the +mode. +In insert mode, most characters are simply put in the buffer at the current cursor position as they are typed; however, some characters are -treated specially. In particular, the following characters are taken from +treated specially. +In particular, the following characters are taken from current tty settings (see .Xr tty 1 ) and have their usual meaning (normal values are in parentheses): kill (^U), -erase (^?), werase (^W), eof (^D), intr (^C), and quit (^\e). In addition to +erase (^?), werase (^W), eof (^D), intr (^C), and quit (^\e). +In addition to the above, the following characters are also treated specially in insert mode: .Bl -tag -width 10n .It Ic ^H Erases previous character. .It Ic ^V -Liternal next. The next character typed is not treated specially (can be used +Liternal next. +The next character typed is not treated specially (can be used to insert the characters being described here). .It Ic ^J ^M -End of line. The current line is read, parsed and executed by the shell. +End of line. +The current line is read, parsed and executed by the shell. .It Ic Puts the editor in command mode (see below). .It Ic ^E Command and file name enumeration (see below). .It Ic ^F -Command and file name completion (see below). If used twice in a row, the +Command and file name completion (see below). +If used twice in a row, the list of possible completions is displayed; if used a third time, the completion is undone. .It Ic ^X @@ -4432,19 +4709,22 @@ above), enabled with .Ic set Fl o Ic vi-tabcomplete . .El .Pp -In command mode, each character is interpreted as a command. Characters that +In command mode, each character is interpreted as a command. +Characters that don't correspond to commands, are illegal combinations of commands, or are -commands that can't be carried out all cause beeps. In the following command -descriptions, an +commands that can't be carried out all cause beeps. +In the following command descriptions, an .Ar n indicates the command may be prefixed by a number (e.g., .Ic 10l moves right 10 characters); if no number prefix is used, .Ar n -is assumed to be 1 unless otherwise specified. The term +is assumed to be 1 unless otherwise specified. +The term .Dq current position refers to the position between the cursor and the character preceding the -cursor. A +cursor. +A .Dq word is a sequence of letters, digits and underscore characters or a sequence of non-letter, non-digit, non-underscore, non-whitespace characters (e.g., @@ -4482,14 +4762,16 @@ Edit line .Ar n using the vi editor; if .Ar n -is not specified, the current line is edited. The actual command executed is +is not specified, the current line is edited. +The actual command executed is .Ic fc Fl e Ic ${VISUAL;-${EDITOR:-vi}} Ar n . .It Ic \&* No and Ic ^X Command or file name expansion is applied to the current big-word (with an appended .Ql * , if the word contains no file globbing characters) -- the big-word is replaced -with the resulting words. If the current big-word is the first on the line (or +with the resulting words. +If the current big-word is the first on the line (or follows one of the following characters: .Ql \&; , .Ql | , @@ -4504,11 +4786,14 @@ Command expansion will match the big-word against all aliases, functions and built-in commands as well as any executable files found by searching the directories in the .Ev PATH -parameter. File name expansion matches the big-word against the files in the -current directory. After expansion, the cursor is places just past the last +parameter. +File name expansion matches the big-word against the files in the +current directory. +After expansion, the cursor is places just past the last word and the editor is in insert mode. .It n\e,\ n^F,\ n,\ and\ n -Command/file name completion. Replace the current big-word with the +Command/file name completion. +Replace the current big-word with the longest unique match obtained after performing command and file name expansion. .Ic is only recognized if the @@ -4526,14 +4811,15 @@ is specified, the possible completion is selected (as reported by the command/file name enumeration command). .It Ic \&= No and Ic ^E -Command/file name enumeration. List all the commands or files that match the -current big-word. +Command/file name enumeration. +List all the commands or files that match the current big-word. .It Ic ^V Display the version of .Nm pdksh ; it is displayed until another key is pressed (this key is ignored). .It Ic @ Ns Ar c -Macro expansion. Execute the commands found in the alias +Macro expansion. +Execute the commands found in the alias .Ar c . .El .Pp @@ -4585,7 +4871,8 @@ Move forward .Ar n big-words. .It Ic % -Find match. The editor looks forward for the nearest parenthesis, bracket or +Find match. +The editor looks forward for the nearest parenthesis, bracket or brace and then moves the cursor to the matching parenthesis, bracket or brace. .It Ar n Ns Ic f Ns Ar c Move forward to the @@ -4675,7 +4962,8 @@ Edit commands .It Ar n Ns Ic a Append text .Ar n -times; goes into insert mode just after the current position. The append is +times; goes into insert mode just after the current position. +The append is only replicated if command mode is re-entered (i.e., is used). .It Ar n Ns Ic A Same as @@ -4684,7 +4972,8 @@ except it appends at the end of the line. .It Ar n Ns Ic i Insert text .Ar n -times; goes into insert mode at the current position. The insertion is only +times; goes into insert mode at the current position. +The insertion is only replicated if command mode is re-entered (i.e., is used). .It Ar n Ns Ic I Same as @@ -4695,7 +4984,8 @@ Substitute the next .Ar n characters (i.e., delete the characters and go into insert mode). .It Ic S -Substitute whole line. All characters from the first non-blank character to the +Substitute whole line. +All characters from the first non-blank character to the end of the line are deleted and insert mode is entered. .It Ar n Ns Ic c Ns Ar move-cmd Change from the current position to the position resulting from @@ -4731,8 +5021,10 @@ Replace the next characters with the character .Ar c . .It Ar n Ns Ic R -Replace. Enter insert mode but overwrite existing characters instead of -inserting before existing characters. The replacement is repeated +Replace. +Enter insert mode but overwrite existing characters instead of +inserting before existing characters. +The replacement is repeated .Ar n times. .It Ar n Ns Ic \&~ @@ -4826,7 +5118,8 @@ deleted and a new prompt to be printed. .Sh BUGS Any bugs in .Nm pdksh -should be reported to pdksh@cs.mun.ca. Please include the version of +should be reported to pdksh@cs.mun.ca. +Please include the version of .Nm pdksh .Po .Ic echo $KSH_VERSION @@ -4843,7 +5136,8 @@ and a copy of your .Pa config.h (the file generated by the .Pa configure -script). New version of +script). +New versions of .Nm pdksh can be obtained from ftp://ftp.cs.mun.ca/pub/pdksh. .Pp @@ -4859,11 +5153,13 @@ domain Korn shell. .Sh AUTHORS This shell is based on the public domain 7th edition Bourne shell clone by Charles Forsyth and parts of the BRL shell by Doug A. Gwyn, Doug Kingston, -Ron Natalie, Arnold Robbins, Lou Salkind, and others. The first release of +Ron Natalie, Arnold Robbins, Lou Salkind, and others. +The first release of .Nm pdksh was created by Eric Gisin, and it was subsequently maintained by John R. MacMillan (change!john@sq.sq.com) and Simon J. Gerraty (sjg@zen.void.oz.au). -The current maintainer is Michael Rendell (michael@cs.mun.ca). The +The current maintainer is Michael Rendell (michael@cs.mun.ca). +The .Pa CONTRIBUTORS file in the source distribution contains a more complete list of people and their part in the shell's development. diff --git a/bin/ksh/ksh.1tbl b/bin/ksh/ksh.1tbl index a89f84f0499..402cbfdc54a 100644 --- a/bin/ksh/ksh.1tbl +++ b/bin/ksh/ksh.1tbl @@ -1,4 +1,4 @@ -.\" $OpenBSD: ksh.1tbl,v 1.30 2000/03/14 20:25:46 aaron Exp $ +.\" $OpenBSD: ksh.1tbl,v 1.31 2000/03/17 18:15:16 aaron Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -51,7 +51,8 @@ .Sh DESCRIPTION .Nm ksh is a command interpreter intended for both interactive and shell -script use. Its command language is a superset of the +script use. +Its command language is a superset of the .Xr sh 1 shell language. .Ss Shell startup @@ -81,8 +82,10 @@ If neither the nor the .Fl s option is specified, the first non-option argument specifies the name -of a file the shell reads commands from. If there are no non-option -arguments, the shell reads commands from the standard input. The name of +of a file the shell reads commands from. +If there are no non-option +arguments, the shell reads commands from the standard input. +The name of the shell (i.e., the contents of $0) is determined as follows: if the .Fl c option is used and there is a non-option argument, it is used as the name; @@ -94,8 +97,8 @@ A shell is if the .Fl i option is used or if both standard input and standard error are attached -to a tty. An interactive shell has job control enabled (if available), -ignores the +to a tty. +An interactive shell has job control enabled (if available), ignores the .Dv SIGINT , .Dv SIGQUIT , and @@ -171,9 +174,11 @@ A privileged shell does not process .Pa $HOME/.profile nor the .Ev ENV -parameter (see below). Instead, the file +parameter (see below). +Instead, the file .Pa /etc/suid_profile -is processed. Clearing the privileged option causes the shell to set +is processed. +Clearing the privileged option causes the shell to set its effective user ID (group ID) to its real user ID (group ID). .Pp If the basename of the name the shell is called with (i.e., argv[0]) @@ -196,7 +201,8 @@ after any profiles are processed), its value is subjected to parameter, command, arithmetic, and tilde .Pq Sq \&~ substitution and the resulting file -(if any) is read and executed. If the +(if any) is read and executed. +If the .Ev ENV parameter is not set (and not .Dv NULL ) @@ -209,7 +215,8 @@ mentioned substitutions have been performed). .Pp The exit status of the shell is 127 if the command file specified on the command line could not be opened, or non-zero if a fatal syntax error -occurred during the execution of a script. In the absence of fatal errors, +occurred during the execution of a script. +In the absence of fatal errors, the exit status is that of the last command executed, or zero, if no command is executed. .Ss Command syntax @@ -227,8 +234,8 @@ and .Ql \&) .Pc . Aside from delimiting words, spaces and tabs are ignored, while newlines -usually delimit commands. The meta-characters are used in building the -following tokens: +usually delimit commands. +The meta-characters are used in building the following tokens: .Ql < , .Ql <& , .Ql > , @@ -267,7 +274,8 @@ or in groups using double .Pq Sq \&" or single .Pq Sq \&' -quotes. Note that the following characters are also treated specially by the +quotes. +Note that the following characters are also treated specially by the shell and must be quoted if they are to represent themselves: .Ql \e , .Ql \&" , @@ -338,8 +346,10 @@ input/output redirections (see .Sx Input/output redirections below), and command words; the only restriction is that parameter assignments come -before any command words. The command words, if any, define the command -that is to be executed and its arguments. The command may be a shell built-in +before any command words. +The command words, if any, define the command +that is to be executed and its arguments. +The command may be a shell built-in command, a function or an external command (i.e., a separate executable file that is located using the .Ev PATH @@ -353,7 +363,8 @@ this is related to the status returned by be executed, the exit status is 126); the exit status of other command constructs (built-in commands, functions, compound-commands, pipelines, lists, etc.) are all well-defined and are described where the construct is -described. The exit status of a command consisting only of parameter +described. +The exit status of a command consisting only of parameter assignments is that of the last command substitution performed during the parameter assignment or 0 is there were no command substitutions. .Pp @@ -362,8 +373,9 @@ Commands can be chained together using the token to form pipelines, in which the standard output of each command but the last is piped (see .Xr pipe 2 ) -to the standard input of the following command. The exit status of a pipeline -is that of its last command. A pipeline may be prefixed by the +to the standard input of the following command. +The exit status of a pipeline is that of its last command. +A pipeline may be prefixed by the .Ql ! reversed word which causes the exit status of the pipeline to be logically complemented: if the original status was 0 the complemented status will be 1; @@ -399,13 +411,15 @@ have equal precedence which is higher than that of .Ql |& and .Ql \&; , -which also have equal precedence. The +which also have equal precedence. +The .Ql & token causes the preceding command to be executed asynchronously; that is, the shell starts the command but does not wait for it to complete (the shell does keep track of the status of asynchronous commands, see .Sx Job control -below). When an asynchronous command is started when job control is disabled +below). +When an asynchronous command is started when job control is disabled (i.e., in most scripts), the command is started with signals .Dv SIGINT and @@ -418,7 +432,8 @@ The operator starts a co-process which is a special kind of asynchronous process (see .Sx Co-processes -below). Note that a command must follow the +below). +Note that a command must follow the .Ql && and .Ql || @@ -430,7 +445,8 @@ or The exit status of a list is that of the last command executed, with the exception of asynchronous lists, for which the exit status is 0. .Pp -Compound commands are created using the following reserved words. These words +Compound commands are created using the following reserved words. +These words are only recognized if they are unquoted and if they are used as the first word of a command (i.e., they can't be preceded by parameter assignments or redirections): @@ -453,7 +469,8 @@ elif for select while } .Sy Note: Some shells (but not this one) execute control structure commands in a subshell when one or more of their file descriptors are redirected, so any -environment changes inside them may fail. To be portable, the +environment changes inside them may fail. +To be portable, the .Ic exec statement should be used instead to redirect file descriptors before the control structure. @@ -461,7 +478,8 @@ control structure. In the following compound command descriptions, command lists (denoted as .Em list ) that are followed by reserved words must end with a semicolon, a newline, or -a (syntactically correct) reserved word. For example, +a (syntactically correct) reserved word. +For example, .Pp .Bl -inset -indent -compact .It Ic { echo foo; echo bar; } @@ -480,12 +498,14 @@ is not. .It Ic \&( Ar list Ic \&) Execute .Ar list -in a subshell. There is no implicit way to pass environment changes from a +in a subshell. +There is no implicit way to pass environment changes from a subshell back to its parent. .It Ic \&{ Ar list Ic \&} Compound construct; .Ar list -is executed, but not in a subshell. Note that +is executed, but not in a subshell. +Note that .Ic \&{ and .Ic \&} @@ -505,19 +525,21 @@ against the specified .Ar pattern Ns s ; the .Ar list -associated with the first successfully matched pattern is executed. Patterns -used in +associated with the first successfully matched pattern is executed. +Patterns used in .Ic case statements are the same as those used for file name patterns except that the restrictions regarding .Ql \&. and .Ql / -are dropped. Note that any unquoted space before and after a pattern is -stripped; any space with a pattern must be quoted. Both the word and the -patterns are subject to parameter, command, and arithmetic substitution as -well as tilde substitution. For historical reasons, open and close braces -may be used instead of +are dropped. +Note that any unquoted space before and after a pattern is +stripped; any space with a pattern must be quoted. +Both the word and the +patterns are subject to parameter, command, and arithmetic substitution, as +well as tilde substitution. +For historical reasons, open and close braces may be used instead of .Ic in and .Ic esac @@ -540,11 +562,12 @@ in the specified word list, the parameter .Ar name is set to the word and .Ar list -is executed. If +is executed. +If .Ic in is not used to specify a word list, the positional parameters ($1, $2, etc.) -are used instead. For historical reasons, open and close braces may be used -instead of +are used instead. +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -573,8 +596,8 @@ is executed; otherwise, the .Ar list following the .Ic elif , -if any, is executed with similar consequences. If all the lists following -the +if any, is executed with similar consequences. +If all the lists following the .Ic if and .Ic elif Ns s @@ -582,7 +605,8 @@ fail (i.e., exit with non-zero status), the .Ar list following the .Ic else -is executed. The exit status of an +is executed. +The exit status of an .Ic if statement is that of non-conditional .Ar list @@ -596,7 +620,8 @@ is executed, the exit status is zero. The .Ic select statement provides an automatic method of presenting the user with a menu and -selecting from it. An enumerated list of the specified +selecting from it. +An enumerated list of the specified .Ar word Ns s is printed on standard error, followed by a prompt .Po @@ -621,13 +646,15 @@ completes, the enumerated list is printed if .Ev REPLY is .Dv NULL , -the prompt is printed and so on. This process continues until an end-of-file +the prompt is printed and so on. +This process continues until an end-of-file is read, an interrupt is received, or a .Ic break -statement is executed inside the loop. If +statement is executed inside the loop. +If .Ic in Ar word Ar ... -is omitted, the positional parameters are used (i.e., $1, $2, etc.). For -historical reasons, open and close braces may be used instead of +is omitted, the positional parameters are used (i.e., $1, $2, etc.). +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -651,10 +678,11 @@ is non-zero. .Xc A .Ic while -is a pre-checked loop. Its body is executed as often as the exit status of -the first +is a pre-checked loop. +Its body is executed as often as the exit status of the first .Ar list -is zero. The exit status of a +is zero. +The exit status of a .Ic while statement is the last exit status of the .Ar list @@ -666,7 +694,8 @@ Defines the function .Ar name (see .Sx Functions -below). Note that redirections specified after a function definition are +below). +Note that redirections specified after a function definition are performed whenever the function is executed, not when the function definition is executed. .It Ar name Ic () Ar command @@ -750,7 +779,8 @@ are evaluated and lazy expression evaluation is used for the .Ql && and .Ql || -operators. This means that in the statement +operators. +This means that in the statement .Pp .Ic \&[[ -r foo && $(< foo) = b*r ]] .Pp @@ -763,15 +793,18 @@ exists and is readable. .El .Ss Quoting Quoting is used to prevent the shell from treating characters or words -specially. There are three methods of quoting. First, +specially. +There are three methods of quoting. +First, .Ql \e quotes the following character, unless it is at the end of a line, in which case both the .Ql \e -and the newline are stripped. Second, a single quote +and the newline are stripped. +Second, a single quote .Pq Sq ' -quotes everything up to the next single quote (this may span lines). Third, -a double quote +quotes everything up to the next single quote (this may span lines). +Third, a double quote .Pq Sq \&" quotes all characters, except .Ql $ , @@ -784,7 +817,8 @@ and .Ql ` inside double quotes have their usual meaning (i.e., parameter, command or arithmetic substitution) except no field splitting is carried out on the -results of double-quoted substitutions. If a +results of double-quoted substitutions. +If a .Ql \e inside a double-quoted string is followed by .Ql \e , @@ -807,13 +841,15 @@ below for a special rule regarding sequences of the form .Ss Aliases There are two types of aliases: normal command aliases and tracked aliases. Command aliases are normally used as a short hand for a long or often used -command. The shell expands command aliases (i.e., substitutes the alias name -for its value) when it reads the first word of a command. An expanded alias -is re-processed to check for more aliases. If a command alias ends in a -space or tab, the following word is also checked for alias expansion. The -alias expansion process stops when a word that is not an alias is found, when -a quoted word is found or when an alias word that is currently being expanded -is found. +command. +The shell expands command aliases (i.e., substitutes the alias name +for its value) when it reads the first word of a command. +An expanded alias is re-processed to check for more aliases. +If a command alias ends in a +space or tab, the following word is also checked for alias expansion. +The alias expansion process stops when a word that is not an alias is found, +when a quoted word is found or when an alias word that is currently being +expanded is found. .Pp The following command aliases are defined automatically by the shell: .Pp @@ -847,22 +883,27 @@ The following command aliases are defined automatically by the shell: .El .Pp Tracked aliases allow the shell to remember where it found a particular -command. The first time the shell does a path search for a command that is -marked as a tracked alias, it saves the full path of the command. The next +command. +The first time the shell does a path search for a command that is +marked as a tracked alias, it saves the full path of the command. +The next time the command is executed, the shell checks the saved path to see that it -is still valid, and if so, avoids repeating the path search. Tracked aliases -can be listed and created using +is still valid, and if so, avoids repeating the path search. +Tracked aliases can be listed and created using .Ic alias -t . Note that changing the .Ev PATH -parameter clears the saved paths for all tracked aliases. If the +parameter clears the saved paths for all tracked aliases. +If the .Ic trackall option is set (i.e., .Ic set Fl o Ic trackall or .Ic set Fl h ) , -the shell tracks all commands. This option is set automatically for -non-interactive shells. For interactive shells, only the following commands are +the shell tracks all commands. +This option is set automatically for +non-interactive shells. +For interactive shells, only the following commands are automatically tracked: .Ic cat , cc , chmod , cp , .Ic date , ed , emacs , grep , @@ -873,8 +914,10 @@ and .Ic who . .Ss Substitution The first step the shell takes in executing a simple-command is to perform -substitutions on the words of the command. There are three kinds of -substitution: parameter, command, and arithmetic. Parameter substitutions, +substitutions on the words of the command. +There are three kinds of +substitution: parameter, command, and arithmetic. +Parameter substitutions, which are described in detail in the next section, take the form .Ic $ Ns Ar name or @@ -890,7 +933,8 @@ If a substitution appears outside of double quotes, the results of the substitution are generally subject to word or field splitting according to the current value of the .Ev IFS -parameter. The +parameter. +The .Ev IFS parameter specifies a list of characters which are used to break a string up into several words; any characters from the set space, tab, and newline that @@ -903,7 +947,8 @@ Sequences of one or more whitespace characters, in combination with zero or no .Pf non- Ev IFS whitespace -characters, delimit a field. As a special case, leading and trailing +characters, delimit a field. +As a special case, leading and trailing .Ev IFS whitespace is stripped (i.e., no leading or trailing empty field is created by it); leading or trailing @@ -932,7 +977,8 @@ The results of substitution are, unless otherwise specified, also subject to brace expansion and file name expansion (see the relevant sections below). .Pp A command substitution is replaced by the output generated by the specified -command, which is run in a subshell. For +command, which is run in a subshell. +For .Ic $( Ns Ar command Ns Ic \&) substitutions, normal quoting rules are used when .Ar command @@ -947,8 +993,8 @@ or .Ql \e is stripped (a .Ql \e -followed by any other character is unchanged). As a special case in command -substitutions, a command of the form +followed by any other character is unchanged). +As a special case in command substitutions, a command of the form .Ic \&< Ar file is interpreted to mean substitute the contents of .Ar file @@ -961,17 +1007,20 @@ but it is carried out more efficiently because no process is started). .Sy Note: .Ic $( Ns Ar command Ns Ic \&) expressions are currently parsed by finding the matching parenthesis, -regardless of quoting. This should be fixed soon. +regardless of quoting. +This should be fixed soon. .Pp Arithmetic substitutions are replaced by the value of the specified expression. For example, the command .Ic echo $((2+3*4)) -prints 14. See +prints 14. +See .Sx Arithmetic expressions for a description of an expression. .Ss Parameters Parameters are shell variables; they can be assigned values and their values -can be accessed using a parameter substitution. A parameter name is either one +can be accessed using a parameter substitution. +A parameter name is either one of the special single punctuation or digit character parameters described below, or a letter followed by zero or more letters or digits .Po @@ -1006,12 +1055,12 @@ or .Pc is set, in which case an error occurs. .Pp -Parameters can be assigned valued in a number of ways. First, the shell -implicitly sets some parameters like +Parameters can be assigned valued in a number of ways. +First, the shell implicitly sets some parameters like .Ic # , PWD , etc.; this is the only way the special single character parameters are set. -Second, parameters are imported from the shell's environment at startup. Third, -parameters can be assigned values on the command line, for example, +Second, parameters are imported from the shell's environment at startup. +Third, parameters can be assigned values on the command line, for example, .Ic FOO=bar sets the parameter .Ev FOO @@ -1020,18 +1069,19 @@ to multiple parameter assignments can be given on a single command line and they can be followed by a simple-command, in which case the assignments are in effect only for the duration of the command (such assignments are also -exported, see below for implications of this). Note that both the parameter -name and the +exported, see below for implications of this). +Note that both the parameter name and the .Ql = -must be unquoted for the shell to recognize a parameter assignment. The fourth -way of setting a parameter is with the +must be unquoted for the shell to recognize a parameter assignment. +The fourth way of setting a parameter is with the .Ic export , .Ic readonly and .Ic typeset commands; see their descriptions in the .Sx Command execution -section. Fifth, +section. +Fifth, .Ic for and .Ic select @@ -1040,7 +1090,8 @@ loops set parameters as well as the .Ic read and .Ic set Fl A -commands. Lastly, parameters can be assigned values using assignment operators +commands. +Lastly, parameters can be assigned values using assignment operators inside arithmetic expressions (see .Sx Arithmetic expressions below) or using the @@ -1058,8 +1109,10 @@ the environment (see .Xr environ 5 ) of commands run by the shell as .Ar name Ns No = Ns Ar value -pairs. The order in which parameters appear in the environment of a command is -unspecified. When the shell starts up, it extracts parameters and their values +pairs. +The order in which parameters appear in the environment of a command is +unspecified. +When the shell starts up, it extracts parameters and their values from its environment and automatically sets the export attribute for those parameters. .Pp @@ -1110,7 +1163,8 @@ it is substituted; otherwise, is printed on standard error (preceded by .Ar name Ns No \&: ) and an error occurs (normally causing termination of a shell script, function -or .-script). If word is omitted the string +or .-script). +If word is omitted the string .Dq parameter null or not set is used instead. .El @@ -1156,7 +1210,8 @@ If .Ar pattern matches the beginning of the value of parameter .Ar name , -the matched text is deleted from the result of substitution. A single +the matched text is deleted from the result of substitution. +A single .Ql # results in the shortest match, and two of them result in the longest match. @@ -1178,8 +1233,8 @@ The following special parameters are implicitly set by the shell and cannot be set directly using assignments: .Bl -tag -width "1 ... 9" .It Ev \&! -Process ID of the last background process started. If no background processes -have been started, the parameter is not set. +Process ID of the last background process started. +If no background processes have been started, the parameter is not set. .It Ev \&# The number of positional parameters (i.e., $1, $2, etc.). .It Ev \&$ @@ -1192,8 +1247,8 @@ The concatenation of the current single letter options (see .Ic set command below for list of options). .It Ev \&? -The exit status of the last non-asynchronous command executed. If the last -command was killed by a signal, +The exit status of the last non-asynchronous command executed. +If the last command was killed by a signal, .Ic \&$\&? is set to 128 plus the signal number. .It Ev 0 @@ -1207,17 +1262,20 @@ option and the .Ar command-name was supplied, or the .Ar file -argument, if it was supplied. If the +argument, if it was supplied. +If the .Ic posix option is not set, .Ic \&$0 is the name of the current function or script. .It Ev 1 ... Ev 9 The first nine positional parameters that were supplied to the shell, function -or .-script. Further positional parameters may be accessed using +or .-script. +Further positional parameters may be accessed using .Ic ${ Ns Ar number Ns Ic \&} . .It Ev \&* -All positional parameters (except parameter 0), i.e., $1, $2, $3... If used +All positional parameters (except parameter 0), i.e., $1, $2, $3... +If used outside of double quotes, parameters are separate words (which are subjected to word splitting); if used within double quotes, parameters are separated by the first character of the @@ -1230,8 +1288,8 @@ is Same as .Ic \&$\&* , unless it is used inside double quotes, in which case a separate word is -generated for each positional parameter. If there are no positional parameters, -no word is generated. +generated for each positional parameter. +If there are no positional parameters, no word is generated. .Ic \&$\&@ can be used to access arguments, verbatim, without losing .Dv NULL @@ -1242,9 +1300,10 @@ The following parameters are set and/or used by the shell: .Bl -tag -width "EXECSHELL" .It Ev \&_ No (underscore) When an external command is executed by the shell, this parameter is set in the -environment of the new process to the path of the executed command. In -interactive use, this parameter is also set in the parent shell to the last -word of the previous command. When +environment of the new process to the path of the executed command. +In interactive use, this parameter is also set in the parent shell to the last +word of the previous command. +When .Ev MAILPATH messages are evaluated, this parameter contains the name of the file that changed (see @@ -1253,27 +1312,31 @@ parameter below). .It Ev CDPATH Search path for the .Ic cd -built-in command. Works the same way as +built-in command. +Works the same way as .Ev PATH for those directories not beginning with .Ql / in .Ic cd -commands. Note that if +commands. +Note that if .Ev CDPATH is set and does not contain .Dq \&. -or contains an empty path, the current directory is not searched. Also, the +or contains an empty path, the current directory is not searched. +Also, the .Ic cd built-in command will display the resulting directory when a match is found in any search path other than the empty path. .It Ev COLUMNS -Set to the number of columns on the terminal or window. Currently set to the +Set to the number of columns on the terminal or window. +Currently set to the .Dq cols value as reported by .Xr stty 1 -if that value is non-zero. This parameter is used by the interactive line -editing modes, and by +if that value is non-zero. +This parameter is used by the interactive line editing modes, and by .Ic select , .Ic set Fl o , and @@ -1283,18 +1346,20 @@ commands to format information columns. If the .Ev VISUAL parameter is not set, this parameter controls the command-line editing mode for -interactive shells. See +interactive shells. +See .Ev VISUAL parameter below for how this works. .It Ev ENV If this parameter is found to be set after any profile files are executed, the -expanded value is used as a shell startup file. It typically contains function -and alias definitions. +expanded value is used as a shell startup file. +It typically contains function and alias definitions. .It Ev ERRNO Integer value of the shell's .Va errno -variable. It indicates the reason the last system call failed. Not yet -implemented. +variable. +It indicates the reason the last system call failed. +Not yet implemented. .It Ev EXECSHELL If set, this parameter is assumed to contain the shell that is to be used to execute commands that @@ -1310,14 +1375,16 @@ command (see below). Like .Ev PATH , but used when an undefined function is executed to locate the file defining the -function. It is also searched when a command can't be found using +function. +It is also searched when a command can't be found using .Ev PATH . See .Sx Functions below for more information. .It Ev HISTFILE -The name of the file used to store command history. When assigned to, history -is loaded from the specified file. Also, several invocations of the shell +The name of the file used to store command history. +When assigned to, history is loaded from the specified file. +Also, several invocations of the shell running on the same machine will share history if their .Ev HISTFILE parameters all point to the same file. @@ -1325,14 +1392,15 @@ parameters all point to the same file. .Sy Note: If .Ev HISTFILE -isn't set, no history file is used. This is different from the original Korn -shell, which uses +isn't set, no history file is used. +This is different from the original Korn shell, which uses .Pa $HOME/.sh_history ; in future, .Nm pdksh may also use a default history file. .It Ev HISTSIZE -The number of commands normally stored for history. The default is 128. +The number of commands normally stored for history. +The default is 128. .It Ev HOME The default directory for the .Ic cd @@ -1345,7 +1413,8 @@ below). Internal field separator, used during substitution and by the .Ic read command, to split values into distinct arguments; normally set to space, tab -and newline. See +and newline. +See .Sx Substitution above for details. .Pp @@ -1363,7 +1432,8 @@ sections, below. The line number of the function or shell script that is currently being executed. .It Ev LINES -Set to the number of lines on the terminal or window. Not yet implemented. +Set to the number of lines on the terminal or window. +Not yet implemented. .It Ev MAIL If set, the user will be informed of the arrival of mail in the named file. This parameter is ignored if the @@ -1375,20 +1445,23 @@ by .Ev MAIL or .Ev MAILPATH . -If set to 0, the shell checks before each prompt. The default is 600 (10 -minutes). +If set to 0, the shell checks before each prompt. +The default is 600 (10 minutes). .It Ev MAILPATH -A list of files to be checked for mail. The list is colon separated, and each -file may be followed by a +A list of files to be checked for mail. +The list is colon separated, and each file may be followed by a .Ql ? -and a message to be printed if new mail has arrived. Command, parameter and +and a message to be printed if new mail has arrived. +Command, parameter and arithmetic substitution is performed on the message, and, during substitution, the parameter .Ev $_ -contains the name of the file. The default message is +contains the name of the file. +The default message is .Dq you have mail in $_ . .It Ev OLDPWD -The previous working directory. Unset if +The previous working directory. +Unset if .Ic cd has not successfully changed directories since the shell started, or if the shell doesn't know where it is. @@ -1404,25 +1477,29 @@ Assigning 1 to this parameter causes to process arguments from the beginning the next time it is invoked. .It Ev PATH A colon separated list of directories that are searched when looking for -commands and .'d files. An empty string resulting from a leading or trailing +commands and .'d files. +An empty string resulting from a leading or trailing colon, or two adjacent colons, is treated as a .Dq \&. , the current directory. .It Ev POSIXLY_CORRECT If set, this parameter causes the .Ic posix -option to be enabled. See +option to be enabled. +See .Sx POSIX mode below. .It Ev PPID The process ID of the shell's parent (read-only). .It Ev PS1 -The primary prompt for interactive shells. Parameter, command, and arithmetic +The primary prompt for interactive shells. +Parameter, command, and arithmetic substitutions are performed, and .Ql ! is replaced with the current command number (see .Ic fc -command below). A literal +command below). +A literal .Ql ! can be put in the prompt by placing .Ql !! @@ -1430,11 +1507,13 @@ in .Ev PS1 . Note that since the command-line editors try to figure out how long the prompt is (so they know how far it is to the edge of the screen), escape codes in -the prompt tend to mess things up. You can tell the shell not to count certain +the prompt tend to mess things up. +You can tell the shell not to count certain sequences (such as escape codes) by prefixing your prompt with a non-printing character (such as control-A) followed by a carriage return and then delimiting -the escape codes with this non-printing character. If you don't have any -non-printing characters, you're out of luck. By the way, don't blame me for +the escape codes with this non-printing character. +If you don't have any non-printing characters, you're out of luck. +By the way, don't blame me for this hack; it's in the original .Xr ksh . Default is @@ -1449,30 +1528,36 @@ used when more input is needed to complete a command. .It Ev PS3 Prompt used by .Ic select -statement when reading a menu selection. Default is +statement when reading a menu selection. +Default is .Dq \&#\&?\ \& . .It Ev PS4 Used to prefix commands that are printed during execution tracing (see .Ic set Fl x -command below). Parameter, command, and arithmetic substitutions are performed -before it is printed. Default is +command below). +Parameter, command, and arithmetic substitutions are performed +before it is printed. +Default is .Dq \&+\ \& . .It Ev PWD -The current working directory. May be unset or +The current working directory. +May be unset or .Dv NULL if the shell doesn't know where it is. .It Ev RANDOM -A simple random number generator. Every time +A simple random number generator. +Every time .Ev RANDOM -is referenced, it is assigned the next number in a random number series. The -point in the series can be set by assigning a number to +is referenced, it is assigned the next number in a random number series. +The point in the series can be set by assigning a number to .Ev RANDOM (see .Xr rand 3 ) . .It Ev REPLY Default parameter for the .Ic read -command if no names are given. Also used in +command if no names are given. +Also used in .Ic select loops to store the value that is read from standard input. .It Ev SECONDS @@ -1486,13 +1571,15 @@ prompt .Pq Ev PS1 . If the time is exceeded, the shell exits. .It Ev TMPDIR -The directory shell temporary files are created in. If this parameter is not +The directory shell temporary files are created in. +If this parameter is not set, or does not contain the absolute path of a writable directory, temporary files are created in .Pa /tmp . .It Ev VISUAL If set, this parameter controls the command-line editing mode for interactive -shells. If the last component of the path specified in this parameter contains +shells. +If the last component of the path specified in this parameter contains the string .Dq vi , .Dq emacs @@ -1511,7 +1598,8 @@ on words starting with an unquoted .Ql ~ . The characters following the tilde, up to the first .Ql / , -if any, are assumed to be a login name. If the login name is empty, +if any, are assumed to be a login name. +If the login name is empty, .Ql + or .Ql - , @@ -1520,9 +1608,11 @@ the value of the .Ev PWD , or .Ev OLDPWD -parameter is substituted, respectively. Otherwise, the password file is +parameter is substituted, respectively. +Otherwise, the password file is searched for the login name, and the tilde expression is substituted with the -user's home directory. If the login name is not found in the password file or +user's home directory. +If the login name is not found in the password file or if any quoting or parameter substitution occurs in the login name, no substitution is performed. .Pp @@ -1564,13 +1654,15 @@ expands to four words: and .Dq ade ) . As noted in the example, brace expressions can be nested and the resulting -words are not sorted. Brace expressions must contain an unquoted comma +words are not sorted. +Brace expressions must contain an unquoted comma .Pq Sq \&, for expansion to occur (i.e., .Ic {} and .Ic {foo} -are not expanded). Brace expansion is carried out after parameter substitution +are not expanded). +Brace expansion is carried out after parameter substitution and before file name generation. .Ss File name patterns A file name pattern is a word containing one or more unquoted @@ -1579,30 +1671,34 @@ or .Ql * characters or .Dq [..] -sequences. Once brace expansion has been performed, the shell replaces file +sequences. +Once brace expansion has been performed, the shell replaces file name patterns with the sorted named of all the files that match the pattern -(if no files match, the word is left unchanged). The pattern elements have the -following meaning: +(if no files match, the word is left unchanged). +The pattern elements have the following meaning: .Bl -tag -width Ds .It Ic \&? Matches any single character. .It Ic \&* Matches any sequence of characters. .It Ic \&[ Ns No .. Ns Ic \&] -Matches any of the characters inside the brackets. Ranges of characters can be +Matches any of the characters inside the brackets. +Ranges of characters can be specified by separating two characters by a .Ql - (e.g., .Dq [a0-9] matches the letter .Dq a -or any digit). In order to represent itself, a +or any digit). +In order to represent itself, a .Ql - must either be quoted or the first or last character in the character list. Similarly, a .Ql \&] must be quoted or the first character in the list if it is to represent itself -instead of the end of the list. Also, a +instead of the end of the list. +Also, a .Ql ! appearing at the start of the list has special meaning (see below), so to represent itself it must be quoted or appear later in the list. @@ -1616,7 +1712,8 @@ except it matches any character not inside the brackets. .Xc .Sm on Matches any string of characters that matches zero or more occurrences of the -specified patterns. Example: The pattern +specified patterns. +Example: The pattern .Ic \&*(foo\&|bar) matches the strings .Dq , @@ -1630,7 +1727,8 @@ etc. .Xc .Sm on Matches any string of characters that matches one or more occurrences of the -specified patterns. Example: The pattern +specified patterns. +Example: The pattern .Ic \&+(foo\&|bar) matches the strings .Dq foo , @@ -1643,7 +1741,8 @@ etc. .Xc .Sm on Matches the empty string or a string that matches one of the specified -patterns. Example: The pattern +patterns. +Example: The pattern .Ic \&?(foo\&|bar) only matches the strings .Dq , @@ -1655,8 +1754,8 @@ and .Ic \&| Ar pattern Ic \&) .Xc .Sm on -Matches a string that matches one of the specified patterns. Example: The -pattern +Matches a string that matches one of the specified patterns. +Example: The pattern .Ic \&@(foo\&|bar) only matches the strings .Dq foo @@ -1667,8 +1766,8 @@ and .Ic \&| Ar pattern Ic \&) .Xc .Sm on -Matches any string that does not match one of the specified patterns. Examples: -The pattern +Matches any string that does not match one of the specified patterns. +Examples: The pattern .Ic \&!(foo\&|bar) matches all strings except .Dq foo @@ -1724,7 +1823,8 @@ expression) are not yet implemented. .Ss Input/output redirection When a command is executed, its standard input, standard output, and standard error (file descriptors 0, 1, and 2, respectively) are normally inherited from -the shell. Three exceptions to this are commands in pipelines, for which +the shell. +Three exceptions to this are commands in pipelines, for which standard input and/or standard output are those set up by the pipeline, asynchronous commands created when job control is disabled, for which standard input is initially set to be from @@ -1738,8 +1838,8 @@ If .Ar file does not exist, it is created; if it does exist, is a regular file and the .Ic noclobber -option is set, an error occurs; otherwise, the file is truncated. Note that -this means the command +option is set, an error occurs; otherwise, the file is truncated. +Note that this means the command .Ic cmd < foo > foo will open .Ar foo @@ -1758,7 +1858,8 @@ Same as .Ic \&> , except if .Ar file -exists it is appended to instead of being truncated. Also, the file is opened +exists it is appended to instead of being truncated. +Also, the file is opened in append mode, so writes always go to the end of the file (see .Fn open 2 ) . .It Ic \&< Ar file @@ -1775,8 +1876,10 @@ After reading the command line containing this kind of redirection (called a the shell copies lines from the command source into a temporary file until a line matching .Ar marker -is read. When the command is executed, standard input is redirected from the -temporary file. If +is read. +When the command is executed, standard input is redirected from the +temporary file. +If .Ar marker contains no quoted characters, the contents of the temporary file are processed as if enclosed in double quotes each time the command is executed, so @@ -1814,16 +1917,19 @@ except the operation is done on standard output. .Pp In any of the above redirections, the file descriptor that is redirected (i.e., standard input or standard output) can be explicitly given by preceding the -redirection with a single digit. Parameter, command, and arithmetic +redirection with a single digit. +Parameter, command, and arithmetic substitutions, tilde substitutions, and (if the shell is interactive) file name generation are all performed on the .Ar file , .Ar marker and .Ar fd -arguments of redirections. Note, however, that the results of any file name +arguments of redirections. +Note, however, that the results of any file name generation are only used if a single file is matched; if multiple files match, -the word with the expanded file name generation characters is used. Note +the word with the expanded file name generation characters is used. +Note that in restricted shells, redirections which can create files cannot be used. .Pp For simple-commands, redirections may appear anywhere in the command; for @@ -1832,7 +1938,8 @@ compound-commands .Ic if statements, etc. .Pc , -any redirections must appear at the end. Redirections are processed after +any redirections must appear at the end. +Redirections are processed after pipelines are created and in the order they are given, so .Pp .Ic cat /foo/bar 2\&>&1 \&> /dev/null \&| cat -n @@ -1927,7 +2034,8 @@ Arithmetic (bit-wise) .Tn NOT . .It Ic \&+\&+ Increment; must be applied to a parameter (not a literal or other expression). -The parameter is incremented by 1. When used as a prefix operator, the result +The parameter is incremented by 1. +When used as a prefix operator, the result is the incremented value of the parameter; when used as a postfix operator, the result is the original value of the parameter. .It Ic \&-\&- @@ -1936,8 +2044,8 @@ Similar to except the parameter is decremented by 1. .It Ic \&, Separates two arithmetic expressions; the left-hand side is evaluated first, -then the right. The result is the value of the expression on the right-hand -side. +then the right. +The result is the value of the expression on the right-hand side. .It Ic = Assignment; variable on the left is set to the value on the right. .It Xo Ic \&*= /= \&+= \&-= \&<\&<= @@ -1957,13 +2065,13 @@ is the same as .It Ic \&|\&| Logical .Tn OR ; -the result is 1 if either argument is non-zero, 0 if not. The right -argument is evaluated only if the left argument is zero. +the result is 1 if either argument is non-zero, 0 if not. +The right argument is evaluated only if the left argument is zero. .It Ic \&&\&& Logical .Tn AND ; -the result is 1 if both arguments are non-zero, 0 if not. The -right argument is evaluated only if the left argument is non-zero. +the result is 1 if both arguments are non-zero, 0 if not. +The right argument is evaluated only if the left argument is non-zero. .It Ic \&| Arithmetic (bit-wise) .Tn OR . @@ -1982,7 +2090,8 @@ Not equal; the result is 0 if both arguments are equal, 1 if not. Less than; the result is 1 if the left argument is less than the right, 0 if not. .It Ic \&<= \&>= \&> -Less than or equal, greater than or equal, greater than. See +Less than or equal, greater than or equal, greater than. +See .Ic \&< . .It Ic \&<\&< \&>\&> Shift left (right); the result is the left argument with its bits shifted left @@ -1991,8 +2100,8 @@ Shift left (right); the result is the left argument with its bits shifted left Addition, subtraction, multiplication, and division. .It Ic % Remainder; the result is the remainder of the division of the left argument by -the right. The sign of the result is unspecified if either argument is -negative. +the right. +The sign of the result is unspecified if either argument is negative. .It Xo Ao Ar arg1 Ac Ic \ \&? .Ao Ar arg2 Ac Ic \ \&: Ao Ar arg3 Ac .Xc @@ -2014,11 +2123,13 @@ The input and output of the co-process can also be manipulated using .Ic \&>\&&p and .Ic \&<\&&p -redirections, respectively. Once a co-process has been started, another can't +redirections, respectively. +Once a co-process has been started, another can't be started until the co-process exits, or until the co-process's input has been redirected using an .Ic exec Ar n Ns Ic \&>\&&p -redirection. If a co-process's input is redirected in this way, the next +redirection. +If a co-process's input is redirected in this way, the next co-process to be started will share the output with the first co-process, unless the output of the initial co-process has been redirected using an .Ic exec Ar n Ns Ic \&<\&&p @@ -2033,11 +2144,14 @@ close that file descriptor (e.g., .Ic exec 3\&>\&&p\&; exec 3>\&>\&&\&- ) . .It In order for co-processes to share a common output, the shell must keep the -write portion of the output pipe open. This means that end-of-file will not be +write portion of the output pipe open. +This means that end-of-file will not be detected until all co-processes sharing the co-process output have exited -(when they all exit, the shell closes its copy of the pipe). This can be +(when they all exit, the shell closes its copy of the pipe). +This can be avoided by redirecting the output to a numbered file descriptor (as this also -causes the shell to close its copy). Note that this behaviour is slightly +causes the shell to close its copy). +Note that this behaviour is slightly different from the original Korn shell which closes its copy of the write portion of the co-process output when the most recently started co-process (instead of when all sharing co-processes) exits. @@ -2056,12 +2170,15 @@ Functions are defined using either Korn shell .Ic function Ar name syntax or the Bourne/POSIX shell .Fn name -syntax (see below for the difference between the two forms). Functions are like +syntax (see below for the difference between the two forms). +Functions are like .Li .-scripts -in that they are executed in the current environment. However, unlike +in that they are executed in the current environment. +However, unlike .Li .-scripts , shell arguments (i.e., positional parameters $1, $2, etc.) are never visible -inside them. When the shell is determining the location of a command, functions +inside them. +When the shell is determining the location of a command, functions are searched after special built-in commands, before regular and non-regular built-ins, and before the .Ev PATH @@ -2080,7 +2197,8 @@ may be used to create undefined functions; when an undefined function is executed, the shell searches the path specified in the .Ev FPATH parameter for a file with the same name as the function, which, if found, is -read and executed. If after executing the file the named function is found to +read and executed. +If after executing the file the named function is found to be defined, the function is executed; otherwise, the normal command search is continued (i.e., the shell searches the regular built-in command table and .Ev PATH ) . @@ -2098,24 +2216,28 @@ which can be set with .Ic typeset \&-ft and .Ic typeset \&-fx , -respectively. When a traced function is executed, the shell's +respectively. +When a traced function is executed, the shell's .Ic xtrace option is turned on for the function's duration; otherwise, the .Ic xtrace -option is turned off. The +option is turned off. +The .Dq export -attribute of functions is currently not used. In the original Korn shell, +attribute of functions is currently not used. +In the original Korn shell, exported functions are visible to shell scripts that are executed. .Pp Since functions are executed in the current shell environment, parameter assignments made inside functions are visible after the function completes. If this is not the desired effect, the .Ic typeset -command can be used inside a function to create a local parameter. Note that -special parameters (e.g., $$, $\&!) can't be scoped in this way. +command can be used inside a function to create a local parameter. +Note that special parameters (e.g., $$, $\&!) can't be scoped in this way. .Pp The exit status of a function is that of the last command executed in the -function. A function can be made to finish immediately using the +function. +A function can be made to finish immediately using the .Ic return command; this may also be used to explicitly specify the exit status. .Pp @@ -2143,12 +2265,13 @@ untouched, so using .Ic getopts inside a function interferes with using .Ic getopts -outside the function). In the future, the following differences will also be -added: +outside the function). +In the future, the following differences will also be added: .Bl -bullet -offset indent .It A separate trap/signal environment will be used during the execution of -functions. This will mean that traps set inside a function will not affect the +functions. +This will mean that traps set inside a function will not affect the shell's traps and signals that are not ignored in the shell (but may be trapped) will have their default effect in a function. .It @@ -2162,22 +2285,22 @@ The shell is intended to be compliant; however, in some cases, .Tn POSIX behaviour is contrary either to the original Korn shell behaviour or to user -convenience. How the shell behaves in these cases is determined by the state -of the +convenience. +How the shell behaves in these cases is determined by the state of the .Ic posix option .Pq Ic set Fl o Ic posix . If it is on, the .Tn POSIX -behaviour is followed; otherwise, it is not. The +behaviour is followed; otherwise, it is not. +The .Ic posix option is set automatically when the shell starts up if the environment contains the .Dv POSIXLY_CORRECT parameter. (The shell can also be compiled so that it is in .Tn POSIX -mode by -default; however, this is usually not desirable). +mode by default; however, this is usually not desirable). .Pp The following is a list of things that are affected by the state of the .Ic posix @@ -2188,15 +2311,16 @@ Occurrences of .Ic \e\&" inside double quoted .Ic `\&.\&.` -command substitutions. In +command substitutions. +In .Tn POSIX mode, the .Ic \e\&" is interpreted when the command is interpreted; in .Pf non- Tn POSIX mode, the -backslash is stripped before the command substitution is interpreted. For -example, +backslash is stripped before the command substitution is interpreted. +For example, .Ic echo \&"`echo \e\&"hi\e\&"`\&" produces .Dq \&"hi\&" @@ -2206,38 +2330,43 @@ mode, .Dq hi in .Pf non- Tn POSIX -mode. To avoid problems, use the +mode. +To avoid problems, use the .Ic $(...) form of command substitution. .It .Ic kill -l -output. In +output. +In .Tn POSIX mode, signal names are listed one per line; in .Pf non- Tn POSIX mode, -signal numbers, names and descriptions are printed in columns. In future, a new -option +signal numbers, names and descriptions are printed in columns. +In future, a new option .Po Fl v \ perhaps .Pc will be added to distinguish the two behaviours. .It .Ic fg -exit status. In +exit status. +In .Tn POSIX mode, the exit status is 0 if no errors occur; in .Pf non- Tn POSIX mode, the exit status is that of the last foregrounded job. .It .Ic eval -exit status. If +exit status. +If .Ic eval gets to see an empty command (i.e., .Ic eval "`false`" ) , its exit status in .Tn POSIX -mode will be 0. In +mode will be 0. +In .Pf non- Tn POSIX mode, it will be the exit status of the last command substitution that was done in the processing of the arguments to @@ -2256,12 +2385,14 @@ mode, options can start with either or .Ql + . .It -Brace expansion (also known as alternation). In +Brace expansion (also known as alternation). +In .Tn POSIX mode, brace expansion is disabled; in .Pf non- Tn POSIX -mode, brace expansion is enabled. Note that +mode, brace expansion is enabled. +Note that .Ic set Fl o Ic posix (or setting the .Ev POSIXLY_CORRECT @@ -2281,7 +2412,8 @@ options; in mode, it does. .It .Ic set -exit status. In +exit status. +In .Tn POSIX mode, the exit status of .Ic set @@ -2290,14 +2422,15 @@ is 0 if there are no errors; in mode, the exit status is that of any command substitutions performed in generating the .Ic set -command. For example, +command. +For example, .Ic set \&-\&- `false`; echo $? prints 0 in .Tn POSIX mode, 1 in .Pf non- Tn POSIX -mode. This construct is used in most -shell scripts that use the old +mode. +This construct is used in most shell scripts that use the old .Xr getopt 1 command. .It @@ -2307,7 +2440,8 @@ Argument expansion of .Ic readonly , and .Ic typeset -commands. In +commands. +In .Tn POSIX mode, normal argument expansion is done; in .Pf non- Tn POSIX @@ -2315,7 +2449,8 @@ mode, field splitting, file globbing, brace expansion, and (normal) tilde expansion are turned off, while assignment tilde expansion is turned on. .It -Signal specification. In +Signal specification. +In .Tn POSIX mode, signals can be specified as digits, only if signal numbers match @@ -2325,13 +2460,15 @@ KILL=9, ALRM=14, and TERM=15); in .Pf non- Tn POSIX mode, signals can always be digits. .It -Alias expansion. In +Alias expansion. +In .Tn POSIX mode, alias expansion is only carried out when reading command words; in .Pf non- Tn POSIX mode, alias expansion is carried out on any -word following an alias that ended in a space. For example, the following +word following an alias that ended in a space. +For example, the following .Ic for loop .Pp @@ -2352,7 +2489,8 @@ in .Pf non- Tn POSIX mode. .It -Test. In +Test. +In .Tn POSIX mode, the expression .Dq Fl t @@ -2360,8 +2498,7 @@ mode, the expression .Dq Ic \&! arguments) is always true as it is a non-zero length string; in .Pf non- Tn POSIX -mode, -it tests if file descriptor 1 is a tty (i.e., the +mode, it tests if file descriptor 1 is a tty (i.e., the .Ar fd argument to the .Fl t @@ -2369,28 +2506,29 @@ test may be left out and defaults to 1). .El .Ss Command execution After evaluation of command-line arguments, redirections and parameter -assignments, the type of command is determined: a special built-in, a +assignments, the type of command is determined: a special built-in, a function, a regular built-in, or the name of a file to execute found using the .Ev PATH -parameter. The checks are made in the above order. Special built-in commands -differ from other commands in that the +parameter. +The checks are made in the above order. +Special built-in commands differ from other commands in that the .Ev PATH parameter is not used to find them, and an error during their execution can cause a non-interactive shell to exit and parameter assignments that are -specified before the command are kept after the command completes. Just to -confuse things, if the +specified before the command are kept after the command completes. +Just to confuse things, if the .Ic posix option is turned off (see .Ic set command below), some special commands are very special in that no field splitting, file globbing, brace expansion, nor tilde expansion is performed -on arguments that look like assignments. Regular built-in commands are -different only in that the +on arguments that look like assignments. +Regular built-in commands are different only in that the .Ev PATH parameter is not used to find them. .Pp The original -.Nm +.Nm ksh and .Tn POSIX differ somewhat in which commands are considered @@ -2439,15 +2577,18 @@ The following described the special and regular built-in commands: .It Ic \&. Ar file Op Ar arg1 ... Execute the commands in .Ar file -in the current environment. The file is searched for in the directories of +in the current environment. +The file is searched for in the directories of .Ev PATH . If arguments are given, the positional parameters may be used to access them while .Ar file -is being executed. If no arguments are given, the positional parameters are +is being executed. +If no arguments are given, the positional parameters are those of the environment the command is used in. .It Ic \&: Op Ar ... -The null command. Exit status is set to zero. +The null command. +Exit status is set to zero. .It Xo Ic alias .Op Fl d | Ic +-t Op Fl r .Op Ic +-px @@ -2459,23 +2600,26 @@ The null command. Exit status is set to zero. .Xc Without arguments, .Ic alias -lists all aliases. For any name without a value, the existing alias is listed. +lists all aliases. +For any name without a value, the existing alias is listed. Any name with a value defines an alias (see .Sx Aliases above). .Pp -When listing aliases, one of two formats is used. Normally, aliases are listed -as +When listing aliases, one of two formats is used. +Normally, aliases are listed as .Ar name Ns No = Ar value , where .Ar value -is quoted. If options were preceded with +is quoted. +If options were preceded with .Ql + , or a lone .Ql + is given on the command line, only .Ar name -is printed. In addition, if the +is printed. +In addition, if the .Fl p option is used, each alias is prefixed with the string .Dq alias\ \& . @@ -2492,7 +2636,8 @@ with the export attribute (exporting an alias has no effect). The .Fl t option indicates that tracked aliases are to be listed/set (values specified on -the command line are ignored for tracked aliases). The +the command line are ignored for tracked aliases). +The .Fl r option indicates that all tracked aliases are to be reset. .Pp @@ -2503,11 +2648,11 @@ listed or set (see .Sx Tilde expansion above). .It Ic bg Op Ar job ... -Resume the specified stopped job(s) in the background. If no jobs are -specified, +Resume the specified stopped job(s) in the background. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic bind Op Fl m @@ -2545,7 +2690,8 @@ is set, it lists the search path for the directory containing .Ar dir . A .Dv NULL -path means the current directory. If +path means the current directory. +If .Ar dir is found in any component of the .Ev CDPATH @@ -2556,13 +2702,15 @@ If .Ar dir is missing, the home directory .Ev HOME -is used. If +is used. +If .Ar dir is .Dq - , the previous working directory is used (see .Ev OLDPWD -parameter). If the +parameter). +If the .Fl L option (logical path) is used or if the .Ic physical @@ -2572,13 +2720,15 @@ command below) isn't set, references to .Dq \&.\&. in .Ar dir -are relative to the path used to get to the directory. If the +are relative to the path used to get to the directory. +If the .Fl P option (physical path) is used or if the .Ic physical option is set, .Dq \&.\&. -is relative to the filesystem directory tree. The +is relative to the filesystem directory tree. +The .Ev PWD and .Ev OLDPWD @@ -2604,11 +2754,13 @@ options are given, .Ar cmd is executed exactly as if the .Ic command -had not been specified, with two exceptions. First, +had not been specified, with two exceptions. +First, .Ar cmd cannot be a shell function, and second, special built-in commands lose their specialness (i.e., redirection and utility errors do not cause the shell to -exit, and command assignments are not permanent). If the +exit, and command assignments are not permanent). +If the .Fl p option is given, a default search path is used instead of the current value of .Ev PATH @@ -2628,10 +2780,12 @@ For special and regular built-in commands and functions, their names are simply printed; for aliases, a command that defines them is printed; and for commands found by searching the .Ev PATH -parameter, the full path of the command is printed. If no command is found +parameter, the full path of the command is printed. +If no command is found (i.e., the path search fails), nothing is printed and .Ic command -exits with a non-zero status. The +exits with a non-zero status. +The .Fl V option is like the .Fl v @@ -2652,7 +2806,8 @@ defaults to 1. .Op Ar arg ... .Xc Prints its arguments (separated by spaces) followed by a newline, to the -standard output. The newline is suppressed if any of the arguments contain the +standard output. +The newline is suppressed if any of the arguments contain the backslash sequence .Ql \ec . See the @@ -2661,7 +2816,8 @@ command below for a list of other backslash sequences that are recognized. .Pp The options are provided for compatibility with .Bx -shell scripts. The +shell scripts. +The .Fl n option suppresses the trailing newline, .Fl e @@ -2678,13 +2834,16 @@ The command is executed without forking, replacing the shell process. .Pp If no command is given except for I/O redirection, the I/O redirection is permanent and the shell is -not replaced. Any file descriptors greater than 2 which are opened or +not replaced. +Any file descriptors greater than 2 which are opened or .Xr dup 2 Ns 'd in this way are not made available to other executed commands (i.e., commands -that are not built-in to the shell). Note that the Bourne shell differs here; +that are not built-in to the shell). +Note that the Bourne shell differs here; it does pass these file descriptors on. .It Ic exit Op Ar status -The shell exits with the specified exit status. If +The shell exits with the specified exit status. +If .Ar status is not specified, the exit status is the current value of the .Ic \&? @@ -2692,9 +2851,9 @@ parameter. .It Xo Ic export Op Fl p .Op Ar parameter Ns Op \&= Ns Ar value .Xc -Sets the export attribute of the named parameters. Exported parameters are -passed in the environment to executed commands. If values are specified, the -named parameters are also assigned. +Sets the export attribute of the named parameters. +Exported parameters are passed in the environment to executed commands. +If values are specified, the named parameters are also assigned. .Pp If no parameters are specified, the names of all parameters with the export attribute are printed one per line, unless the @@ -2713,14 +2872,18 @@ A command that exits with a non-zero status. .Ar first and .Ar last -select commands from the history. Commands can be selected by history number -or a string specifying the most recent command starting with that string. The +select commands from the history. +Commands can be selected by history number +or a string specifying the most recent command starting with that string. +The .Fl l option lists the command on stdout, and .Fl n -inhibits the default command numbers. The +inhibits the default command numbers. +The .Fl r -option reverses the order of the list. Without +option reverses the order of the list. +Without .Fl l , the selected commands are edited by the editor specified with the .Fl e @@ -2751,10 +2914,11 @@ are replaced with This command is usually accessed with the predefined .Ic alias r='fx -e -' . .It Ic fg Op Ar job ... -Resume the specified job(s) in the foreground. If no jobs are specified, +Resume the specified job(s) in the foreground. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic getopts Ar optstring name @@ -2765,9 +2929,11 @@ parameters, if no arguments are given) and to check for legal options. .Ar optstring contains the option letters that .Ic getopts -is to recognize. If a letter is followed by a colon, the option is expected to -have an argument. Options that do not take arguments may be grouped in a single -argument. If an option takes an argument and the option character is not the +is to recognize. +If a letter is followed by a colon, the option is expected to +have an argument. +Options that do not take arguments may be grouped in a single argument. +If an option takes an argument and the option character is not the last character of the argument it is found in, the remainder of the argument is taken to be the option's argument; otherwise, the next argument is the option's argument. @@ -2793,14 +2959,15 @@ mark or a colon is placed in .Ar name (indicating an illegal option or missing argument, respectively) and .Ev OPTAG -is set to the option character that caused the problem. An error message is -also printed to standard error if +is set to the option character that caused the problem. +An error message is also printed to standard error if .Ar optstring does not being with a colon. .Pp When the end of the options is encountered, .Ic getopts -exits with a non-zero exit status. Options end at the first (non-option +exits with a non-zero exit status. +Options end at the first (non-option argument) argument that does not start with a .Ql - , or when a @@ -2821,9 +2988,11 @@ may lead to unexpected results. .It Xo Ic hash Op Fl r .Op Ar name ... .Xc -Without arguments, any hashed executable command pathnames are listed. The +Without arguments, any hashed executable command pathnames are listed. +The .Fl r -option causes all hashed commands to be removed from the hash table. Each +option causes all hashed commands to be removed from the hash table. +Each .Ar name is searched as if it were a command name and added to the hash table if it is an executable command. @@ -2831,14 +3000,18 @@ an executable command. .Op Ar job ... .Xc Display information about the specified job(s); if no jobs are specified, all -jobs are displayed. The +jobs are displayed. +The .Fl n option causes information to be displayed only for jobs that have changed -state since the last notification. If the +state since the last notification. +If the .Fl l -option is used, the process ID of each process in a job is also listed. The +option is used, the process ID of each process in a job is also listed. +The .Fl p -option causes only the process group of each job to be printed. See +option causes only the process group of each job to be printed. +See .Sx Job control below for the format of .Ar job @@ -2851,10 +3024,12 @@ and the displayed job. .Ar pgrp No } Ar ... .Xc Send the specified signal to the specified jobs, process IDs, or process -groups. If no signal is specified, the +groups. +If no signal is specified, the .Dv TERM -signal is sent. If a job is specified, the signal is sent to the job's -process group. See +signal is sent. +If a job is specified, the signal is sent to the job's process group. +See .Sx Job control below for the format of .Ar job . @@ -2867,8 +3042,10 @@ a short description of them are printed. .It Ic let Op Ar expression ... Each expression is evaluated (see .Sx Arithmetic expressions -above). If all expressions are successfully evaluated, the exit status is 0 (1) -if the last expression evaluated to non-zero (zero). If an error occurs during +above). +If all expressions are successfully evaluated, the exit status is 0 (1) +if the last expression evaluated to non-zero (zero). +If an error occurs during the parsing or evaluation of an expression, the exit status is greater than 1. Since expressions may need to be quoted, .Ic (( Ar expr Ic )) @@ -2881,9 +3058,11 @@ is syntactic sugar for .Xc .Ic print prints its arguments on the standard output, separated by spaces and -terminated with a newline. The +terminated with a newline. +The .Fl n -option suppresses the newline. By default, certain C escapes are translated. +option suppresses the newline. +By default, certain C escapes are translated. These include .Ql \eb , .Ql \ef , @@ -2904,7 +3083,8 @@ option. .Ql \e expansion may be inhibited with the .Fl r -option. The +option. +The .Fl s option prints to the history file instead of standard output, the .Fl u @@ -2929,11 +3109,13 @@ command, which does not process .Ql \e sequences unless the .Fl e -option is given. As above, the +option is given. +As above, the .Fl n option suppresses the trailing newline. .It Ic pwd Op Fl LP -Print the present working directory. If the +Print the present working directory. +If the .Fl L option is used or if the .Ic physical @@ -2941,7 +3123,8 @@ option (see .Ic set command below) isn't set, the logical path is printed (i.e., the path used to .Ic cd -to the current directory). If the +to the current directory). +If the .Fl P option (physical path) is used or if the .Ic physical @@ -2956,17 +3139,19 @@ using the .Ev IFS parameter (see .Sx Substitution -above), and assigns each field to the specified parameters. If there are more -parameters than fields, the extra parameters are set to +above), and assigns each field to the specified parameters. +If there are more parameters than fields, the extra parameters are set to .Dv NULL , or alternatively, if there are more fields than parameters, the last parameter -is assigned the remaining fields (inclusive of any separating spaces). If no -parameters are specified, the +is assigned the remaining fields (inclusive of any separating spaces). +If no parameters are specified, the .Ev REPLY -parameter is used. If the input line ends in a backslash and the +parameter is used. +If the input line ends in a backslash and the .Fl r option was not used, the backslash and the newline are stripped and more input -is read. If no input is read, +is read. +If no input is read, .Ic read exits with a non-zero status. .Pp @@ -2983,7 +3168,8 @@ options cause input to be read from file descriptor .Ar n or the current co-process (see .Sx Co-processes -above for comments on this), respectively. If the +above for comments on this), respectively. +If the .Fl s option is used, input is saved to the history file. .It Xo Ic readonly Op Fl p @@ -2991,8 +3177,10 @@ option is used, input is saved to the history file. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Sets the read-only attribute of the named parameters. If values are given, -parameters are set to them before setting the attribute. Once a parameter is +Sets the read-only attribute of the named parameters. +If values are given, +parameters are set to them before setting the attribute. +Once a parameter is made read-only, it cannot be unset and its value cannot be changed. .Pp If no parameters are specified, the names of all parameters with the read-only @@ -3009,8 +3197,8 @@ script, with exit status .Ar status . If no .Ar status -is given, the exit status of the last executed command is used. If used -outside of a function or +is given, the exit status of the last executed command is used. +If used outside of a function or .Ic \&. script, it has the same effect as .Ic exit . @@ -3062,7 +3250,8 @@ the rest are left untouched. All new parameters are created with the export attribute. .It Fl b Ic notify Print job notification messages asynchronously, instead of just before the -prompt. Only used if job control is enabled +prompt. +Only used if job control is enabled .Pq Fl m . .It Fl C Ic noclobber Prevent @@ -3076,7 +3265,8 @@ must be used to force an overwrite Exit (after executing the .Dv ERR trap) as soon as an error occurs or a command fails (i.e., exits with a -non-zero status). This does not apply to commands whose exit status is +non-zero status). +This does not apply to commands whose exit status is explicitly tested by a shell construct such as .Ic if , .Ic until , @@ -3090,34 +3280,40 @@ Do not expand file name patterns. .It Fl h Ic trackall Create tracked aliases for all executed commands (see .Sx Aliases -above). Enabled by default for non-interactive shells. +above). +Enabled by default for non-interactive shells. .It Fl i Ic interactive -Enable interactive mode. This can only be set/unset when the shell is invoked. +Enable interactive mode. +This can only be set/unset when the shell is invoked. .It Fl k Ic keyword Parameter assignments are recognized anywhere in a command. .It Fl l Ic login -The shell is a login shell. This can only be set/unset when the shell is +The shell is a login shell. +This can only be set/unset when the shell is invoked (see .Sx Shell startup above). .It Fl m Ic monitor Enable job control (default for interactive shells). .It Fl n lc noexec -Do not execute any commands. Useful for checking the syntax of scripts +Do not execute any commands. +Useful for checking the syntax of scripts (ignored if interactive). .It Fl p Ic privileged Set automatically if, when the shell starts, the read UID or GID does not match -the effective UID (EUID) or GID (EGID), respectively. See +the effective UID (EUID) or GID (EGID), respectively. +See .Sx Shell startup above for a description of what this means. .It Fl r Ic restricted -Enable restricted mode. This option can only be used when the shell is invoked. +Enable restricted mode. +This option can only be used when the shell is invoked. See .Sx Shell startup above for a description of what this means. .It Fl s Ic stdin -If used where the shell is invoked, commands are read from standard input. Set -automatically if the shell is invoked with no arguments. +If used where the shell is invoked, commands are read from standard input. +Set automatically if the shell is invoked with no arguments. .Pp When .Fl s @@ -3154,8 +3350,8 @@ Enable brace expansion (a.k.a., alternation). Enable BRL emacs-like command-line editing (interactive shells only); see .Sx Emacs editing mode. .It Ic gmacs -Enable gmacs-like command-line editing (interactive shells only). Currently -identical to emacs editing except that transpose (^T) acts slightly +Enable gmacs-like command-line editing (interactive shells only). +Currently identical to emacs editing except that transpose (^T) acts slightly differently. .It Ic ignoreeof The shell will not (easily) exit when end-of-file is read; @@ -3167,13 +3363,15 @@ is read 13 times in a row. .It Ic nohup Do not kill running jobs with a .Dv HUP -signal when a login shell exists. Currently set by default, but this will +signal when a login shell exists. +Currently set by default, but this will change in the future to be compatible with the original Korn shell (which doesn't have this option, but does send the .Dv HUP signal). .It Ic nolog -No effect. In the original Korn shell, this prevents function definitions from +No effect. +In the original Korn shell, this prevents function definitions from being stored in the history file. .It Ic physical Causes the @@ -3188,9 +3386,9 @@ directories instead of .Dq logical directories (i.e., the shell handles .Dq \&.\&. , -which allows the user to be oblivious of symbolic links to directories). Clear -by default. Note that setting this option does not affect the current value of -the +which allows the user to be oblivious of symbolic links to directories). +Clear by default. +Note that setting this option does not affect the current value of the .Ev PWD parameter; only the .Ic cd @@ -3204,13 +3402,15 @@ commands above for more details. .It Ic posix Enable .Tn POSIX -mode. See +mode. +See .Sx POSIX mode above. .It Ic vi Enable vi-like command-line editing (interactive shells only). .It Ic viraw -No effect. In the original Korn shell, unless +No effect. +In the original Korn shell, unless .Ic viraw was set, the vi command-line mode would let the tty driver do the work until .Tn ESC @@ -3227,10 +3427,12 @@ If this option is not set, characters in the range 128-160 are printed as is, which may cause problems. .It Ic vi-tabcomplete In vi command-line editing, do command and file name completion when tab (^I) -is entered in insert mode. This is the default. +is entered in insert mode. +This is the default. .El .Pp -These options can also be used upon invocation of the shell. The current set of +These options can also be used upon invocation of the shell. +The current set of options (with single letter names) can be found in the parameter .Dv \&- . .Ic set Fl o @@ -3239,11 +3441,12 @@ with no option name will list all the options and whether each is on or off; will print the long names of all options that are currently on. .Pp Remaining arguments, if any, are positional parameters and are assigned, in -order, to the positional parameters (i.e., $1, $2, etc.). If options end with +order, to the positional parameters (i.e., $1, $2, etc.). +If options end with .Ql -- -and there are no remaining arguments, all positional parameters are cleared. If -no options or arguments are given, the values of all names are printed. For -unknown historical reasons, a lone +and there are no remaining arguments, all positional parameters are cleared. +If no options or arguments are given, the values of all names are printed. +For unknown historical reasons, a lone .Ql - option is treated specially -- it clears both the .Fl x @@ -3266,15 +3469,18 @@ defaults to 1. evaluates the .Ar expression and returns zero status if true, 1 status if false, or greater than 1 if there -was an error. It is normally used as the condition command of +was an error. +It is normally used as the condition command of .Ic if and .Ic while -statements. The following basic expressions are available: +statements. +The following basic expressions are available: .Bl -tag -width 17n .It Ar str .Ar str -has non-zero length. Note that there is the potential for problems if +has non-zero length. +Note that there is the potential for problems if .Ar str turns out to be an operator (e.g., .Fl r ) . @@ -3350,8 +3556,8 @@ Shell .Ar option is set (see .Ic set -command above for a list of options). As a non-standard extension, if the -option starts with a +command above for a list of options). +As a non-standard extension, if the option starts with a .Ql ! , the test is negated; the test always fails if .Ar option @@ -3389,7 +3595,8 @@ is the same file as second .It Fl t Op Ar fd File descriptor .Ar fd -is a tty device. If the +is a tty device. +If the .Ic posix option is not set, .Ar fd @@ -3452,7 +3659,8 @@ is a file descriptor number), the .Ic test command will attempt to fake it for all tests that operate on files (except the .Fl e -test). For example, +test). +For example, .Ic \&[ -w /dev/fd/2 \&] tests if file descriptor 2 is writable. .Pp @@ -3495,7 +3703,8 @@ instead. .Xc If a .Ar pipeline -is given, the times used to execute the pipeline are reported. If no pipeline +is given, the times used to execute the pipeline are reported. +If no pipeline is given, then the user and system time used by the shell itself, and all the commands it has run since it was started, are reported. The times reported are the real time (elapsed time from start to finish), @@ -3515,7 +3724,8 @@ is a simple command), in which case the output is slightly longer: .Dl user 0.00 .Dl sys 0.00 .Pp -(the number of digits after the decimal may vary from system to system). Note +(the number of digits after the decimal may vary from system to system). +Note that simple redirections of standard error do not effect the output of the time command: .Pp @@ -3550,7 +3760,8 @@ or .Dv ALRM ) or the number of the signal (see .Ic kill -l -command above). There are two special signals: +command above). +There are two special signals: .Dv EXIT (also known as 0), which is executed when the shell is about to exit, and .Dv ERR , @@ -3563,7 +3774,8 @@ option were see -- see .Ic set command above). .Dv EXIT -handlers are executed in the environment of the last executed command. Note +handlers are executed in the environment of the last executed command. +Note that for non-interactive shells, the trap handler cannot be changed for signals that were ignored when the shell started. .Pp @@ -3598,7 +3810,8 @@ A command that exits with a zero value. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Display or set parameter attributes. With no +Display or set parameter attributes. +With no .Ar name arguments, parameter attributes are displayed; if no options are used, the current attributes of all parameters are printed as @@ -3616,7 +3829,8 @@ arguments are given, the attributes of the named parameters are set .Pq Ic \&- or cleared .Pq Ic \&+ . -Values for parameters may optionally be specified. If +Values for parameters may optionally be specified. +If .Ic typeset is used inside a function, any newly created parameters are local to the function. @@ -3625,7 +3839,8 @@ When .Fl f is used, .Ic typeset -operates on the attributes of functions. As with parameters, if no +operates on the attributes of functions. +As with parameters, if no .Ar name Ns s are given, functions are listed with their values (i.e., definitions) unless options are introduced with @@ -3635,24 +3850,31 @@ in which case only the function names are reported. .It Fl L Ns Ar n Left justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Leading whitespace (and zeros, if used with the +assigned value) is used. +Leading whitespace (and zeros, if used with the .Fl Z -option) is stripped. If necessary, values are either truncated or space padded +option) is stripped. +If necessary, values are either truncated or space padded to fit the field width. .It Fl R Ns Ar n Right justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Trailing whitespace is stripped. If necessary, values +assigned value) is used. +Trailing whitespace is stripped. +If necessary, values are either stripped of leading characters or space padded to make them fit the field width. .It Fl Z Ns Ar n -Zero fill attribute. If not combined with +Zero fill attribute. +If not combined with .Fl L , this is the same as .Fl R , @@ -3661,19 +3883,23 @@ except zero padding is used instead of space padding. Integer attribute. .Ar n specifies the base to use when displaying the integer (if not specified, the -base given in the first assignment is used). Parameters with this attribute may +base given in the first assignment is used). +Parameters with this attribute may be assigned values containing arithmetic expressions. .It Fl U -Unsigned integer attribute. Integers are printed as unsigned values (only +Unsigned integer attribute. +Integers are printed as unsigned values (only useful when combined with the .Fl i -option). This option is not in the original Korn shell. +option). +This option is not in the original Korn shell. .It Fl f -Function mode. Display or set functions and their attributes, instead of -parameters. +Function mode. +Display or set functions and their attributes, instead of parameters. .It Fl l -Lower case attribute. All upper case characters in values are converted to -lower case. (In the original Korn shell, this parameter meant +Lower case attribute. +All upper case characters in values are converted to lower case. +(In the original Korn shell, this parameter meant .Dq long integer when used with the .Fl i @@ -3682,52 +3908,63 @@ option.) Print complete .Ic typeset commands that can be used to re-create the attributes (but not the values) or -parameters. This is the default action (option exists for ksh93 compatibility). +parameters. +This is the default action (option exists for ksh93 compatibility). .It Fl r -Read-only attribute. Parameters with this attribute may not be assigned to or -unset. Once this attribute is set, it can not be turned off. +Read-only attribute. +Parameters with this attribute may not be assigned to or unset. +Once this attribute is set, it can not be turned off. .It Fl t -Tag attribute. Has no meaning to the shell; provided for application use. +Tag attribute. +Has no meaning to the shell; provided for application use. .Pp For functions, .Fl t -is the trace attribute. When functions with the trace attribute are executed, -the +is the trace attribute. +When functions with the trace attribute are executed, the .Ic xtrace .Pq Fl x shell option is temporarily turned on. .It Fl u -Upper case attribute. All lower case characters in values are converted to -upper case. (In the original Korn shell, this parameter meant +Upper case attribute. +All lower case characters in values are converted to upper case. +(In the original Korn shell, this parameter meant .Dq unsigned integer when used with the .Fl i option, which meant upper case letters would never be used for bases greater -than 10. See the +than 10. +See the .Fl U option.) .Pp For functions, .Fl u -is the undefined attribute. See +is the undefined attribute. +See .Sx Functions above for the implications of this. .It Fl x -Export attribute. Parameters (or functions) are placed in the environment of -any executed commands. Exported functions are not yet implemented. +Export attribute. +Parameters (or functions) are placed in the environment of +any executed commands. +Exported functions are not yet implemented. .El .It Xo Ic ulimit Op Fl acdfHlmnpsStvw .Op Ar value .Xc -Display or set process limits. If no options are used, the file size limit +Display or set process limits. +If no options are used, the file size limit .Pq Fl f is assumed. .Ar value , if specified, may be either an arithmetic expression or the word .Dq unlimited . The limits affect the shell and any processes created by the shell after a -limit is imposed. Note that some systems may not allow limits to be increased -once they are set. Also note that the types of limits available are system +limit is imposed. +Note that some systems may not allow limits to be increased +once they are set. +Also note that the types of limits available are system dependent -- some systems have only the .Fl f limit. @@ -3815,9 +4052,11 @@ and is equivalent (on most systems) to the octal mask .It Xo Ic unalias Op Fl adt .Op Ar name1 ... .Xc -The aliases for the given names are removed. If the +The aliases for the given names are removed. +If the .Fl a -option is used, all aliases are removed. If the +option is used, all aliases are removed. +If the .Fl t or .Fl d @@ -3836,7 +4075,8 @@ or functions The exit status is non-zero if any of the parameters were already unset, zero otherwise. .It Ic wait Op Ar job ... -Wait for the specified job(s) to finish. The exit status of +Wait for the specified job(s) to finish. +The exit status of .Ic wait is that of the last specified job; if the last job is killed by a signal, the exit status is 128 + the number of the signal (see @@ -3844,7 +4084,8 @@ exit status is 128 + the number of the signal (see above); if the last specified job can't be found (because it never existed, or had already finished), the exit status of .Ic wait -is 127. See +is 127. +See .Sx Job control below for the format of .Ar job . @@ -3859,7 +4100,8 @@ signal is received. If no jobs are specified, .Ic wait waits for all currently running jobs (if any) to finish and exits with a zero -status. If job monitoring is enabled, the completion status of jobs is printed +status. +If job monitoring is enabled, the completion status of jobs is printed (this is not the case when jobs are explicitly specified). .It Xo Ic whence Op Fl pv .Op Ar name ... @@ -3867,11 +4109,13 @@ status. If job monitoring is enabled, the completion status of jobs is printed For each .Ar name , the type of command is listed (reserved word, built-in, alias, -function, tracked alias, or executable). If the +function, tracked alias, or executable). +If the .Fl p option is used, a path search is performed even if .Ar name -is a reserved word, alias, etc. Without the +is a reserved word, alias, etc. +Without the .Fl v option, .Ic whence @@ -3879,7 +4123,8 @@ is similar to .Ic command Fl v except that .Ic whence -will find reserved words and won't print aliases as alias commands. With the +will find reserved words and won't print aliases as alias commands. +With the .Fl v option, .Ic whence @@ -3896,17 +4141,19 @@ status is non-zero. .El .Ss Job control Job control refers to the shell's ability to monitor and control jobs, which -are processes or groups of processes created for commands or pipelines. At a -minimum, the shell keeps track of the status of the background (i.e., +are processes or groups of processes created for commands or pipelines. +At a minimum, the shell keeps track of the status of the background (i.e., asynchronous) jobs that currently exist; this information can be displayed using the .Ic jobs -commands. If job control is fully enabled (using +commands. +If job control is fully enabled (using .Ic set Fl m or .Ic set Fl o Ic monitor ) , as it is for interactive shells, the processes of a job are placed in their -own process group. Foreground jobs can be stopped by typing the suspend +own process group. +Foreground jobs can be stopped by typing the suspend character from the terminal (normally ^Z), jobs can be restarted in either the foreground or background using the .Ic fg @@ -3921,11 +4168,12 @@ commands like .Ic read cannot be. .Pp -When a job is created, it is assigned a job number. For interactive shells, -this number is printed inside +When a job is created, it is assigned a job number. +For interactive shells, this number is printed inside .Dq \&[..\&] , followed by the process IDs of the processes in the job when an asynchronous -command is run. A job may be referred to in +command is run. +A job may be referred to in .Ic bg , .Ic fg , .Ic jobs , @@ -4000,12 +4248,14 @@ The job was stopped by the indicated .It Ar signal-description Op Dq core dumped The job was killed by a signal (e.g., memory fault, hangup, etc.; use .Ic kill -l -for a list of signal descriptions). The +for a list of signal descriptions). +The .Dq core dumped message indicates the process created a core file. .El .It Ar command -is the command that created the process. If there are multiple processes in +is the command that created the process. +If there are multiple processes in the job, each process will have a line showing its .Ar command and possibly its @@ -4018,10 +4268,12 @@ state, the shell warns the user that there are stopped jobs and does not exit. If another attempt is immediately made to exit the shell, the stopped jobs are sent a .Dv SIGHUP -signal and the shell exits. Similarly, if the +signal and the shell exits. +Similarly, if the .Ic nohup option is not set and there are running jobs when an attempt is made to exit -a login shell, the shell warns the user and does not exit. If another attempt +a login shell, the shell warns the user and does not exit. +If another attempt is immediately made to exit the shell, the running jobs are sent a .Dv SIGHUP signal and the shell exits. @@ -4060,11 +4312,14 @@ The line is scrolled horizontally as necessary. .Ss Emacs editing mode When the .Ic emacs -option is set, interactive input line editing is enabled. Warning: This mode is +option is set, interactive input line editing is enabled. +Warning: This mode is slightly different from the emacs mode in the original Korn shell and the 8th -bit is stripped in emacs mode. In this mode, various editing commands +bit is stripped in emacs mode. +In this mode, various editing commands (typically bound to one or more control characters) cause immediate actions -without waiting for a newline. Several editing commands are bound to particular +without waiting for a newline. +Several editing commands are bound to particular control characters when the shell is invoked; these binding can be changed using the following commands: .Bl -tag -width Ds @@ -4079,15 +4334,15 @@ which should consist of a control character (which may be written using caret notation, i.e., ^X), optionally preceded by one of the two prefix characters. Future input of the .Ar string -will cause the editing command to be immediately invoked. Note that although -only two prefix characters (usually +will cause the editing command to be immediately invoked. +Note that although only two prefix characters (usually .Tn ESC and ^X) are supported, some -multi-character sequences can be supported. The following binds the arrow keys -on an +multi-character sequences can be supported. +The following binds the arrow keys on an .Tn ANSI -terminal, or xterm (these are in the default bindings). Of course -some escape sequences won't work out quite this nicely. +terminal, or xterm (these are in the default bindings). +Of course some escape sequences won't work out quite this nicely. .Pp .Bl -item -compact .It @@ -4115,24 +4370,28 @@ will afterwards be immediately replaced by the given string, which may contain editing commands. .El .Pp -The following is a list of available editing commands. Each description starts -with the name of the command, an +The following is a list of available editing commands. +Each description starts with the name of the command, an .Ar n (if the command can be prefixed with a count), and any keys the command is bound to by default (written using caret notation, i.e., .Tn "ASCII ESC" character is -written as ^[). A count prefix for a command is entered using the sequence +written as ^[). +A count prefix for a command is entered using the sequence .Ic ^\&[ Ns Ar n , where .Ar n is a sequence of 1 or more digits; unless otherwise specified, if a count is -omitted, it defaults to 1. Note that editing command names are used only with -the +omitted, it defaults to 1. +Note that editing command names are used only with the .Ic bind -command. Furthermore, many editing commands are useful only on terminals with -a visible cursor. The default bindings were chosen to resemble corresponding -Emacs key bindings. The users' tty characters (e.g., +command. +Furthermore, many editing commands are useful only on terminals with +a visible cursor. +The default bindings were chosen to resemble corresponding +Emacs key bindings. +The users' tty characters (e.g., .Dv ERASE ) are bound to reasonable substitutes and override the default bindings. @@ -4142,8 +4401,8 @@ Useful as a response to a request for a .Ic search-history pattern in order to about the search. .It Ic auto-insert Ar n -Simply causes the character to appear as literal input. Most ordinary -characters are bound to this. +Simply causes the character to appear as literal input. +Most ordinary characters are bound to this. .It Ic backward-char Ar n Ic ^B Moves the cursor backward .Ar n @@ -4171,11 +4430,13 @@ is placed at the beginning of the line. .It Ic complete ^[^[ .It Ic complete ^I Automatically completes as much as is unique of the command name or the file -name containing the cursor. If the entire remaining command or file name is +name containing the cursor. +If the entire remaining command or file name is unique, a space is printed after its completion, unless it is a directory name in which case .Ql / -is appended. If there is no command or file name with the current partialword +is appended. +If there is no command or file name with the current partialword as its prefix, a bell character is output (usually causing a beep to be sounded). .It Ic complete-command ^X^[ @@ -4213,7 +4474,8 @@ words. .It Ic down-history Ar n Ic ^N Scrolls the history buffer forward .Ar n -lines (later). Each input line originally starts just after the last entry +lines (later). +Each input line originally starts just after the last entry in the history buffer, so .Ic down-history is not useful until either @@ -4245,7 +4507,8 @@ Places the cursor where the mark is and sets the mark to where the cursor was. Appends a .Ql * to the current word and replaces the word with the result of performing file -globbing on the word. If no files match the pattern, the bell is rung. +globbing on the word. +If no files match the pattern, the bell is rung. .It Ic forward-char Ar n Ic ^F Moves the cursor forward .Ar n @@ -4268,7 +4531,8 @@ is not specified; otherwise deletes characters between the cursor and column .Ar n . .It Ic list ^[? Prints a sorted, columnated list of command named or file names (if any) that -can complete the partial word containing the cursor. Directoary names have +can complete the partial word containing the cursor. +Directoary names have .Ql / appended to them. .It Ic list-command ^X? @@ -4276,16 +4540,17 @@ Prints a sorted, columnated list of command names (if any) that can complete the partial word containg the cursor. .It Ic list-file ^X^Y Prints a sorted, comunated list of file names (if any) that can complete the -partial word containing the cursor. File type indicators are appended as -described under +partial word containing the cursor. +File type indicators are appended as described under .Ic list above. .It Ic newline ^J , ^M -Causes the current input line to be processed by the shell. The current cursor -position may be anywhere on the line. +Causes the current input line to be processed by the shell. +The current cursor position may be anywhere on the line. .It Ic newline-and-next ^O Causes the current input line to be processed by the shell, and the next line -from history becomes the current line. This is only useful after an +from history becomes the current line. +This is only useful after an .Ic up-history or .ic search-history . @@ -4313,21 +4578,26 @@ Search forward in the current line for the .Ar n Ns th occurrence of the next character typed. .It Ic search-history ^R -Enter incremental search mode. The internal history list is searched -backwards for commands matching the input. An initial +Enter incremental search mode. +The internal history list is searched +backwards for commands matching the input. +An initial .Ql ^ -in the search string anchors the search. The abort key will leave search mode. -Other commands will be executed after leaving search mode. Successive +in the search string anchors the search. +The abort key will leave search mode. +Other commands will be executed after leaving search mode. +Successive .Ic search-history commands continue searching backward to the next previous occurrence of the -pattern. The history buffer retains only a finite number of lines; the oldest +pattern. +The history buffer retains only a finite number of lines; the oldest are discarded as necessary. .It Ic set-mark-command ^[ Ns No Set the mark at the cursor position. .It Ic stuff On systems supporting it, puhses the bound character back onto the terminal -input where it may receive special processing by the terminal handler. This -is useful for the BRL ^T mini-systat feature, for example. +input where it may receive special processing by the terminal handler. +This is useful for the BRL ^T mini-systat feature, for example. .It Ic stuff-reset Acts like .Ic stuff , @@ -4347,7 +4617,8 @@ Uppercase the next .Ar n words. .It Ic version ^V -Display the version of ksh. The current edit buffer is restored as soon as any +Display the version of ksh. +The current edit buffer is restored as soon as any key is pressed (the key is then processed, unless it is a space). .It Ic yank ^Y Inserts the most recently killed text string at the current cursor position. @@ -4399,28 +4670,34 @@ Like vi, there are two modes -- .Dq insert mode and .Dq command -mode. In insert mode, most characters are simply put in the buffer at the +mode. +In insert mode, most characters are simply put in the buffer at the current cursor position as they are typed; however, some characters are -treated specially. In particular, the following characters are taken from +treated specially. +In particular, the following characters are taken from current tty settings (see .Xr tty 1 ) and have their usual meaning (normal values are in parentheses): kill (^U), -erase (^?), werase (^W), eof (^D), intr (^C), and quit (^\e). In addition to +erase (^?), werase (^W), eof (^D), intr (^C), and quit (^\e). +In addition to the above, the following characters are also treated specially in insert mode: .Bl -tag -width 10n .It Ic ^H Erases previous character. .It Ic ^V -Liternal next. The next character typed is not treated specially (can be used +Liternal next. +The next character typed is not treated specially (can be used to insert the characters being described here). .It Ic ^J ^M -End of line. The current line is read, parsed and executed by the shell. +End of line. +The current line is read, parsed and executed by the shell. .It Ic Puts the editor in command mode (see below). .It Ic ^E Command and file name enumeration (see below). .It Ic ^F -Command and file name completion (see below). If used twice in a row, the +Command and file name completion (see below). +If used twice in a row, the list of possible completions is displayed; if used a third time, the completion is undone. .It Ic ^X @@ -4432,19 +4709,22 @@ above), enabled with .Ic set Fl o Ic vi-tabcomplete . .El .Pp -In command mode, each character is interpreted as a command. Characters that +In command mode, each character is interpreted as a command. +Characters that don't correspond to commands, are illegal combinations of commands, or are -commands that can't be carried out all cause beeps. In the following command -descriptions, an +commands that can't be carried out all cause beeps. +In the following command descriptions, an .Ar n indicates the command may be prefixed by a number (e.g., .Ic 10l moves right 10 characters); if no number prefix is used, .Ar n -is assumed to be 1 unless otherwise specified. The term +is assumed to be 1 unless otherwise specified. +The term .Dq current position refers to the position between the cursor and the character preceding the -cursor. A +cursor. +A .Dq word is a sequence of letters, digits and underscore characters or a sequence of non-letter, non-digit, non-underscore, non-whitespace characters (e.g., @@ -4482,14 +4762,16 @@ Edit line .Ar n using the vi editor; if .Ar n -is not specified, the current line is edited. The actual command executed is +is not specified, the current line is edited. +The actual command executed is .Ic fc Fl e Ic ${VISUAL;-${EDITOR:-vi}} Ar n . .It Ic \&* No and Ic ^X Command or file name expansion is applied to the current big-word (with an appended .Ql * , if the word contains no file globbing characters) -- the big-word is replaced -with the resulting words. If the current big-word is the first on the line (or +with the resulting words. +If the current big-word is the first on the line (or follows one of the following characters: .Ql \&; , .Ql | , @@ -4504,11 +4786,14 @@ Command expansion will match the big-word against all aliases, functions and built-in commands as well as any executable files found by searching the directories in the .Ev PATH -parameter. File name expansion matches the big-word against the files in the -current directory. After expansion, the cursor is places just past the last +parameter. +File name expansion matches the big-word against the files in the +current directory. +After expansion, the cursor is places just past the last word and the editor is in insert mode. .It n\e,\ n^F,\ n,\ and\ n -Command/file name completion. Replace the current big-word with the +Command/file name completion. +Replace the current big-word with the longest unique match obtained after performing command and file name expansion. .Ic is only recognized if the @@ -4526,14 +4811,15 @@ is specified, the possible completion is selected (as reported by the command/file name enumeration command). .It Ic \&= No and Ic ^E -Command/file name enumeration. List all the commands or files that match the -current big-word. +Command/file name enumeration. +List all the commands or files that match the current big-word. .It Ic ^V Display the version of .Nm pdksh ; it is displayed until another key is pressed (this key is ignored). .It Ic @ Ns Ar c -Macro expansion. Execute the commands found in the alias +Macro expansion. +Execute the commands found in the alias .Ar c . .El .Pp @@ -4585,7 +4871,8 @@ Move forward .Ar n big-words. .It Ic % -Find match. The editor looks forward for the nearest parenthesis, bracket or +Find match. +The editor looks forward for the nearest parenthesis, bracket or brace and then moves the cursor to the matching parenthesis, bracket or brace. .It Ar n Ns Ic f Ns Ar c Move forward to the @@ -4675,7 +4962,8 @@ Edit commands .It Ar n Ns Ic a Append text .Ar n -times; goes into insert mode just after the current position. The append is +times; goes into insert mode just after the current position. +The append is only replicated if command mode is re-entered (i.e., is used). .It Ar n Ns Ic A Same as @@ -4684,7 +4972,8 @@ except it appends at the end of the line. .It Ar n Ns Ic i Insert text .Ar n -times; goes into insert mode at the current position. The insertion is only +times; goes into insert mode at the current position. +The insertion is only replicated if command mode is re-entered (i.e., is used). .It Ar n Ns Ic I Same as @@ -4695,7 +4984,8 @@ Substitute the next .Ar n characters (i.e., delete the characters and go into insert mode). .It Ic S -Substitute whole line. All characters from the first non-blank character to the +Substitute whole line. +All characters from the first non-blank character to the end of the line are deleted and insert mode is entered. .It Ar n Ns Ic c Ns Ar move-cmd Change from the current position to the position resulting from @@ -4731,8 +5021,10 @@ Replace the next characters with the character .Ar c . .It Ar n Ns Ic R -Replace. Enter insert mode but overwrite existing characters instead of -inserting before existing characters. The replacement is repeated +Replace. +Enter insert mode but overwrite existing characters instead of +inserting before existing characters. +The replacement is repeated .Ar n times. .It Ar n Ns Ic \&~ @@ -4826,7 +5118,8 @@ deleted and a new prompt to be printed. .Sh BUGS Any bugs in .Nm pdksh -should be reported to pdksh@cs.mun.ca. Please include the version of +should be reported to pdksh@cs.mun.ca. +Please include the version of .Nm pdksh .Po .Ic echo $KSH_VERSION @@ -4843,7 +5136,8 @@ and a copy of your .Pa config.h (the file generated by the .Pa configure -script). New version of +script). +New versions of .Nm pdksh can be obtained from ftp://ftp.cs.mun.ca/pub/pdksh. .Pp @@ -4859,11 +5153,13 @@ domain Korn shell. .Sh AUTHORS This shell is based on the public domain 7th edition Bourne shell clone by Charles Forsyth and parts of the BRL shell by Doug A. Gwyn, Doug Kingston, -Ron Natalie, Arnold Robbins, Lou Salkind, and others. The first release of +Ron Natalie, Arnold Robbins, Lou Salkind, and others. +The first release of .Nm pdksh was created by Eric Gisin, and it was subsequently maintained by John R. MacMillan (change!john@sq.sq.com) and Simon J. Gerraty (sjg@zen.void.oz.au). -The current maintainer is Michael Rendell (michael@cs.mun.ca). The +The current maintainer is Michael Rendell (michael@cs.mun.ca). +The .Pa CONTRIBUTORS file in the source distribution contains a more complete list of people and their part in the shell's development. diff --git a/bin/ksh/sh.1 b/bin/ksh/sh.1 index 679a8fa2e3b..8082546623f 100644 --- a/bin/ksh/sh.1 +++ b/bin/ksh/sh.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: sh.1,v 1.16 1999/07/05 19:50:53 aaron Exp $ +.\" $OpenBSD: sh.1,v 1.17 2000/03/17 18:15:16 aaron Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -79,8 +79,10 @@ If neither the nor the .Fl s option is specified, the first non-option argument specifies the name -of a file the shell reads commands from. If there are no non-option -arguments, the shell reads commands from the standard input. The name of +of a file the shell reads commands from. +If there are no non-option +arguments, the shell reads commands from the standard input. +The name of the shell (i.e., the contents of $0) is determined as follows: if the .Fl c option is used and there is a non-option argument, it is used as the name; @@ -92,8 +94,8 @@ A shell is if the .Fl i option is used or if both standard input and standard error are attached -to a tty. An interactive shell has job control enabled (if available), -ignores the +to a tty. +An interactive shell has job control enabled (if available), ignores the .Dv SIGINT , .Dv SIGQUIT , and @@ -169,9 +171,11 @@ A privileged shell does not process .Pa $HOME/.profile nor the .Ev ENV -parameter (see below). Instead, the file +parameter (see below). +Instead, the file .Pa /etc/suid_profile -is processed. Clearing the privileged option causes the shell to set +is processed. +Clearing the privileged option causes the shell to set its effective user ID (group ID) to its real user ID (group ID). .Pp If the basename of the name the shell is called with (i.e., argv[0]) @@ -194,7 +198,8 @@ after any profiles are processed), its value is subjected to parameter, command, arithmetic, and tilde .Pq Sq \&~ substitution and the resulting file -(if any) is read and executed. If the +(if any) is read and executed. +If the .Ev ENV parameter is not set (and not .Dv NULL ) @@ -207,7 +212,8 @@ mentioned substitutions have been performed). .Pp The exit status of the shell is 127 if the command file specified on the command line could not be opened, or non-zero if a fatal syntax error -occurred during the execution of a script. In the absence of fatal errors, +occurred during the execution of a script. +In the absence of fatal errors, the exit status is that of the last command executed, or zero, if no command is executed. .Ss Command syntax @@ -225,8 +231,8 @@ and .Ql \&) .Pc . Aside from delimiting words, spaces and tabs are ignored, while newlines -usually delimit commands. The meta-characters are used in building the -following tokens: +usually delimit commands. +The meta-characters are used in building the following tokens: .Ql < , .Ql <& , .Ql << , @@ -260,7 +266,8 @@ or in groups using double .Pq Sq \&" or single .Pq Sq \&' -quotes. Note that the following characters are also treated specially by the +quotes. +Note that the following characters are also treated specially by the shell and must be quoted if they are to represent themselves: .Ql \e , .Ql \&" , @@ -331,8 +338,10 @@ input/output redirections (see .Sx Input/output redirections below), and command words; the only restriction is that parameter assignments come -before any command words. The command words, if any, define the command -that is to be executed and its arguments. The command may be a shell built-in +before any command words. +The command words, if any, define the command +that is to be executed and its arguments. +The command may be a shell built-in command, a function or an external command (i.e., a separate executable file that is located using the .Ev PATH @@ -346,7 +355,8 @@ this is related to the status returned by be executed, the exit status is 126); the exit status of other command constructs (built-in commands, functions, compound-commands, pipelines, lists, etc.) are all well-defined and are described where the construct is -described. The exit status of a command consisting only of parameter +described. +The exit status of a command consisting only of parameter assignments is that of the last command substitution performed during the parameter assignment or 0 is there were no command substitutions. .Pp @@ -355,8 +365,9 @@ Commands can be chained together using the token to form pipelines, in which the standard output of each command but the last is piped (see .Xr pipe 2 ) -to the standard input of the following command. The exit status of a pipeline -is that of its last command. A pipeline may be prefixed by the +to the standard input of the following command. +The exit status of a pipeline is that of its last command. +A pipeline may be prefixed by the .Ql ! reversed word which causes the exit status of the pipeline to be logically complemented: if the original status was 0 the complemented status will be 1; @@ -387,18 +398,20 @@ is non-zero. .Ql && and .Ql || -have equal precedence which is higher that that of +have equal precedence which is higher than that of .Ql & , .Ql |& and .Ql \&; , -which also have equal precedence. The +which also have equal precedence. +The .Ql & token causes the preceding command to be executed asynchronously; that is, the shell starts the command but does not wait for it to complete (the shell does keep track of the status of asynchronous commands, see .Sx Job control -below). When an asynchronous command is started when job control is disabled +below). +When an asynchronous command is started when job control is disabled (i.e., in most scripts), the command is started with signals .Dv SIGINT and @@ -418,7 +431,8 @@ or The exit status of a list is that of the last command executed, with the exception of asynchronous lists, for which the exit status is 0. .Pp -Compound commands are created using the following reserved words. These words +Compound commands are created using the following reserved words. +These words are only recognized if they are unquoted and if they are used as the first word of a command (i.e., they can't be preceded by parameter assignments or redirections): @@ -435,7 +449,8 @@ elif for time then } .Sy Note: Some shells (but not this one) execute control structure commands in a subshell when one or more of their file descriptors are redirected, so any -environment changes inside them may fail. To be portable, the +environment changes inside them may fail. +To be portable, the .Ic exec statement should be used instead to redirect file descriptors before the control structure. @@ -443,7 +458,8 @@ control structure. In the following compound command descriptions, command lists (denoted as .Em list ) that are followed by reserved words must end with a semicolon, a newline, or -a (syntactically correct) reserved word. For example, +a (syntactically correct) reserved word. +For example, .Pp .Bl -inset -indent -compact .It Ic { echo foo; echo bar; } @@ -462,12 +478,14 @@ is not. .It Ic \&( Ar list Ic \&) Execute .Ar list -in a subshell. There is no implicit way to pass environment changes from a +in a subshell. +There is no implicit way to pass environment changes from a subshell back to its parent. .It Ic \&{ Ar list Ic \&} Compound construct; .Ar list -is executed, but not in a subshell. Note that +is executed, but not in a subshell. +Note that .Ic \&{ and .Ic \&} @@ -487,19 +505,21 @@ against the specified .Ar pattern Ns s ; the .Ar list -associated with the first successfully matched pattern is executed. Patterns -used in +associated with the first successfully matched pattern is executed. +Patterns used in .Ic case statements are the same as those used for file name patterns except that the restrictions regarding .Ql \&. and .Ql / -are dropped. Note that any unquoted space before and after a pattern is -stripped; any space with a pattern must be quoted. Both the word and the +are dropped. +Note that any unquoted space before and after a pattern is +stripped; any space with a pattern must be quoted. +Both the word and the patterns are subject to parameter, command, and arithmetic substitution, as -well as tilde substitution. For historical reasons, open and close braces -may be used instead of +well as tilde substitution. +For historical reasons, open and close braces may be used instead of .Ic in and .Ic esac @@ -522,11 +542,12 @@ in the specified word list, the parameter .Ar name is set to the word and .Ar list -is executed. If +is executed. +If .Ic in is not used to specify a word list, the positional parameters ($1, $2, etc.) -are used instead. For historical reasons, open and close braces may be used -instead of +are used instead. +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -555,8 +576,8 @@ is executed; otherwise, the .Ar list following the .Ic elif , -if any, is executed with similar consequences. If all the lists following -the +if any, is executed with similar consequences. +If all the lists following the .Ic if and .Ic elif Ns s @@ -564,7 +585,8 @@ fail (i.e., exit with non-zero status), the .Ar list following the .Ic else -is executed. The exit status of an +is executed. +The exit status of an .Ic if statement is that of non-conditional .Ar list @@ -584,10 +606,11 @@ is non-zero. .Xc A .Ic while -is a pre-checked loop. Its body is executed as often as the exit status of -the first +is a pre-checked loop. +Its body is executed as often as the exit status of the first .Ar list -is zero. The exit status of a +is zero. +The exit status of a .Ic while statement is the last exit status of the .Ar list @@ -599,7 +622,8 @@ Defines the function .Ar name (see .Sx Functions -below). Note that redirections specified after a function definition are +below). +Note that redirections specified after a function definition are performed whenever the function is executed, not when the function definition is executed. .It Ar name Ic () Ar command @@ -611,15 +635,18 @@ below). .El .Ss Quoting Quoting is used to prevent the shell from treating characters or words -specially. There are three methods of quoting. First, +specially. +There are three methods of quoting. +First, .Ql \e quotes the following character, unless it is at the end of a line, in which case both the .Ql \e -and the newline are stripped. Second, a single quote +and the newline are stripped. +Second, a single quote .Pq Sq ' -quotes everything up to the next single quote (this may span lines). Third, -a double quote +quotes everything up to the next single quote (this may span lines). +Third, a double quote .Pq Sq \&" quotes all characters, except .Ql $ , @@ -632,7 +659,8 @@ and .Ql ` inside double quotes have their usual meaning (i.e., parameter, command or arithmetic substitution) except no field splitting is carried out on the -results of double-quoted substitutions. If a +results of double-quoted substitutions. +If a .Ql \e inside a double-quoted string is followed by .Ql \e , @@ -655,13 +683,15 @@ below for a special rule regarding sequences of the form .Ss Aliases There are two types of aliases: normal command aliases and tracked aliases. Command aliases are normally used as a short hand for a long or often used -command. The shell expands command aliases (i.e., substitutes the alias name -for its value) when it reads the first word of a command. An expanded alias -is re-processed to check for more aliases. If a command alias ends in a -space or tab, the following word is also checked for alias expansion. The -alias expansion process stops when a word that is not an alias is found, when -a quoted word is found or when an alias word that is currently being expanded -is found. +command. +The shell expands command aliases (i.e., substitutes the alias name +for its value) when it reads the first word of a command. +An expanded alias is re-processed to check for more aliases. +If a command alias ends in a +space or tab, the following word is also checked for alias expansion. +The alias expansion process stops when a word that is not an alias is found, +when a quoted word is found or when an alias word that is currently being +expanded is found. .Pp The following command aliases are defined automatically by the shell: .Pp @@ -673,22 +703,26 @@ The following command aliases are defined automatically by the shell: .El .Pp Tracked aliases allow the shell to remember where it found a particular -command. The first time the shell does a path search for a command that is -marked as a tracked alias, it saves the full path of the command. The next +command. +The first time the shell does a path search for a command that is +marked as a tracked alias, it saves the full path of the command. +The next time the command is executed, the shell checks the saved path to see that it -is still valid, and if so, avoids repeating the path search. Tracked aliases -can be listed and created using +is still valid, and if so, avoids repeating the path search. +Tracked aliases can be listed and created using .Ic alias -t . Note that changing the .Ev PATH -parameter clears the saved paths for all tracked aliases. If the +parameter clears the saved paths for all tracked aliases. +If the .Ic trackall option is set (i.e., .Ic set Fl o Ic trackall or .Ic set Fl h ) , -the shell tracks all commands. This option is set automatically for -non-interactive shells. For interactive shells, only the following commands are +the shell tracks all commands. +This option is set automatically for non-interactive shells. +For interactive shells, only the following commands are automatically tracked: .Ic cat , cc , chmod , cp , .Ic date , ed , emacs , grep , @@ -699,14 +733,16 @@ and .Ic who . .Ss Substitution The first step the shell takes in executing a simple-command is to perform -substitutions on the words of the command. There are three kinds of -substitution: parameter, command, and arithmetic. Parameter substitutions, +substitutions on the words of the command. +There are three kinds of +substitution: parameter, command, and arithmetic. +Parameter substitutions, which are described in detail in the next section, take the form -.Ic $name +.Ic $ Ns Ar name or -.Ic ${...} ; +.Ic ${ Ns Ar ... Ns Ic \&} ; command substitutions take the form -.Ic $( Ns Ar command Ns Ic ) +.Ic $( Ns Ar command Ns Ic \&) or .Ic ` Ns Ar command Ns Ic ` ; and arithmetic substitutions take the form @@ -716,7 +752,8 @@ If a substitution appears outside of double quotes, the results of the substitution are generally subject to word or field splitting according to the current value of the .Ev IFS -parameter. The +parameter. +The .Ev IFS parameter specifies a list of characters which are used to break a string up into several words; any characters from the set space, tab, and newline that @@ -729,7 +766,8 @@ Sequences of one or more whitespace characters, in combination with zero or no .Pf non- Ev IFS whitespace -characters, delimit a field. As a special case, leading and trailing +characters, delimit a field. +As a special case, leading and trailing .Ev IFS whitespace is stripped (i.e., no leading or trailing empty field is created by it); leading or trailing @@ -756,7 +794,8 @@ string, no field splitting is done; if the parameter is unset, the default value of space, tab, and newline is used. .Pp Also, note that the field splitting applies only to the immediate result of -the substitution. Using the previous example, the substitution for $VAR:E +the substitution. +Using the previous example, the substitution for $VAR:E results in the fields: .Dq A , .Dq B , @@ -779,8 +818,9 @@ The results of substitution are, unless otherwise specified, also subject to brace expansion and file name expansion (see the relevant sections below). .Pp A command substitution is replaced by the output generated by the specified -command, which is run in a subshell. For -.Ic $( Ns Ar command Ns Ic ) +command, which is run in a subshell. +For +.Ic $( Ns Ar command Ns Ic \&) substitutions, normal quoting rules are used when .Ar command is parsed; however, for the @@ -794,8 +834,8 @@ or .Ql \e is stripped (a .Ql \e -followed by any other character is unchanged). As a special case in command -substitutions, a command of the form +followed by any other character is unchanged). +As a special case in command substitutions, a command of the form .Ic \&< Ar file is interpreted to mean substitute the contents of .Ar file @@ -808,17 +848,20 @@ but it is carried out more efficiently because no process is started). .Sy Note: .Ic $( Ns Ar command Ns Ic \&) expressions are currently parsed by finding the matching parenthesis, -regardless of quoting. This should be fixed soon. +regardless of quoting. +This should be fixed soon. .Pp Arithmetic substitutions are replaced by the value of the specified expression. For example, the command .Ic echo $((2+3*4)) -prints 14. See +prints 14. +See .Sx Arithmetic expressions for a description of an expression. .Ss Parameters Parameters are shell variables; they can be assigned values and their values -can be accessed using a parameter substitution. A parameter name is either one +can be accessed using a parameter substitution. +A parameter name is either one of the special single punctuation or digit character parameters described below, or a letter followed by zero or more letters or digits .Po @@ -831,10 +874,9 @@ or .Ic ${ Ns Ar name Ns Ic \&} , where .Ar name -is a parameter name. If substitution is performed on a parameter that is not -set, a -.Dv NULL -string is substituted unless the +is a parameter name. +If substitution is performed on a parameter that is not set, a +null string is substituted unless the .Ic nounset option .Po @@ -844,12 +886,12 @@ or .Pc is set, in which case an error occurs. .Pp -Parameters can be assigned valued in a number of ways. First, the shell -implicitly sets some parameters like +Parameters can be assigned valued in a number of ways. +First, the shell implicitly sets some parameters like .Ic # , PWD , etc.; this is the only way the special single character parameters are set. -Second, parameters are imported from the shell's environment at startup. Third, -parameters can be assigned values on the command line, for example, +Second, parameters are imported from the shell's environment at startup. +Third, parameters can be assigned values on the command line, for example, .Ic FOO=bar sets the parameter .Ev FOO @@ -858,25 +900,27 @@ to multiple parameter assignments can be given on a single command line and they can be followed by a simple-command, in which case the assignments are in effect only for the duration of the command (such assignments are also -exported, see below for implications of this). Note that both the parameter -name and the +exported, see below for implications of this). +Note that both the parameter name and the .Ql = -must be unquoted for the shell to recognize a parameter assignment. The fourth -way of setting a parameter is with the +must be unquoted for the shell to recognize a parameter assignment. +The fourth way of setting a parameter is with the .Ic export , .Ic readonly and .Ic typeset commands; see their descriptions in the .Sx Command execution -section. Fifth, +section. +Fifth, .Ic for loops set parameters as well as the .Ic getopts , .Ic read and .Ic set Fl A -commands. Lastly, parameters can be assigned values using assignment operators +commands. +Lastly, parameters can be assigned values using assignment operators inside arithmetic expressions (see .Sx Arithmetic expressions below) or using the @@ -894,8 +938,10 @@ the environment (see .Xr environ 5 ) of commands run by the shell as .Ar name Ns No = Ns Ar value -pairs. The order in which parameters appear in the environment of a command is -unspecified. When the shell starts up, it extracts parameters and their values +pairs. +The order in which parameters appear in the environment of a command is +unspecified. +When the shell starts up, it extracts parameters and their values from its environment and automatically sets the export attribute for those parameters. .Pp @@ -946,7 +992,8 @@ it is substituted; otherwise, is printed on standard error (preceded by .Ar name Ns No \&: ) and an error occurs (normally causing termination of a shell script, function -or .-script). If word is omitted the string +or .-script). +If word is omitted the string .Dq parameter null or not set is used instead. .El @@ -989,7 +1036,8 @@ If .Ar pattern matches the beginning of the value of parameter .Ar name , -the matched text is deleted from the result of substitution. A single +the matched text is deleted from the result of substitution. +A single .Ql # results in the shortest match, and two of them result in the longest match. @@ -1008,8 +1056,8 @@ The following special parameters are implicitly set by the shell and cannot be set directly using assignments: .Bl -tag -width "1 ... 9" .It Ev \&! -Process ID of the last background process started. If no background processes -have been started, the parameter is not set. +Process ID of the last background process started. +If no background processes have been started, the parameter is not set. .It Ev \&# The number of positional parameters (i.e., $1, $2, etc.). .It Ev \&$ @@ -1022,8 +1070,8 @@ The concatenation of the current single letter options (see .Ic set command below for list of options). .It Ev \&? -The exit status of the last non-asynchronous command executed. If the last -command was killed by a signal, +The exit status of the last non-asynchronous command executed. +If the last command was killed by a signal, .Ic \&$\&? is set to 128 plus the signal number. .It Ev 0 @@ -1037,17 +1085,20 @@ option and the .Ar command-name was supplied, or the .Ar file -argument, if it was supplied. If the +argument, if it was supplied. +If the .Ic posix option is not set, .Ic \&$0 is the name of the current function or script. .It Ev 1 ... Ev 9 The first nine positional parameters that were supplied to the shell, function -or .-script. Further positional parameters may be accessed using +or .-script. +Further positional parameters may be accessed using .Ic ${ Ns Ar number Ns Ic \&} . .It Ev \&* -All positional parameters (except parameter 0), i.e., $1, $2, $3... If used +All positional parameters (except parameter 0), i.e., $1, $2, $3... +If used outside of double quotes, parameters are separate words (which are subjected to word splitting); if used within double quotes, parameters are separated by the first character of the @@ -1060,8 +1111,8 @@ is Same as .Ic \&$\&* , unless it is used inside double quotes, in which case a separate word is -generated for each positional parameter. If there are no positional parameters, -no word is generated. +generated for each positional parameter. +If there are no positional parameters, no word is generated. .Ic \&$\&@ can be used to access arguments, verbatim, without losing .Dv NULL @@ -1073,39 +1124,45 @@ The following parameters are set and/or used by the shell: .It Ev CDPATH Search path for the .Ic cd -built-in command. Works the same way as +built-in command. +Works the same way as .Ev PATH for those directories not beginning with .Ql / in .Ic cd -commands. Note that if +commands. +Note that if .Ev CDPATH is set and does not contain .Dq \&. -or contains an empty path, the current directory is not searched. Also, the +or contains an empty path, the current directory is not searched. +Also, the .Ic cd built-in command will display the resulting directory when a match is found in any search path other than the empty path. .It Ev COLUMNS -Set to the number of columns on the terminal or window. Currently set to the +Set to the number of columns on the terminal or window. +Currently set to the .Dq cols value as reported by .Xr stty 1 -if that value is non-zero. This parameter is used by +if that value is non-zero. +This parameter is used by .Ic set Fl o and .Ic kill -l commands to format information columns. .It Ev ENV If this parameter is found to be set after any profile files are executed, the -expanded value is used as a shell startup file. It typically contains function -and alias definitions. +expanded value is used as a shell startup file. +It typically contains function and alias definitions. .It Ev ERRNO Integer value of the shell's .Va errno -variable. It indicates the reason the last system call failed. Not yet -implemented. +variable. +It indicates the reason the last system call failed. +Not yet implemented. .It Ev EXECSHELL If set, this parameter is assumed to contain the shell that is to be used to execute commands that @@ -1121,7 +1178,8 @@ command (see below). Like .Ev PATH , but used when an undefined function is executed to locate the file defining the -function. It is also searched when a command can't be found using +function. +It is also searched when a command can't be found using .Ev PATH . See .Sx Functions @@ -1138,7 +1196,8 @@ below). Internal field separator, used during substitution and by the .Ic read command, to split values into distinct arguments; normally set to space, tab -and newline. See +and newline. +See .Sx Substitution above for details. .Pp @@ -1151,9 +1210,11 @@ The version of shell and the date the version was created (read-only). The line number of the function or shell script that is currently being executed. .It Ev LINES -Set to the number of lines on the terminal or window. Not yet implemented. +Set to the number of lines on the terminal or window. +Not yet implemented. .It Ev OLDPWD -The previous working directory. Unset if +The previous working directory. +Unset if .Ic cd has not successfully changed directories since the shell started, or if the shell doesn't know where it is. @@ -1169,14 +1230,16 @@ Assigning 1 to this parameter causes to process arguments from the beginning the next time it is invoked. .It Ev PATH A colon separated list of directories that are searched when looking for -commands and .'d files. An empty string resulting from a leading or trailing +commands and .'d files. +An empty string resulting from a leading or trailing colon, or two adjacent colons, is treated as a .Dq \&. , the current directory. .It Ev POSIXLY_CORRECT If set, this parameter causes the .Ic posix -option to be enabled. See +option to be enabled. +See .Sx POSIX mode below. .It Ev PPID @@ -1195,11 +1258,13 @@ used when more input is needed to complete a command. .It Ev PS4 Used to prefix commands that are printed during execution tracing (see .Ic set Fl x -command below). The prompt is printed verbatim (i.e., no substitutions are -done). Default is +command below). +The prompt is printed verbatim (i.e., no substitutions are done). +Default is .Dq \&+\ \& . .It Ev PWD -The current working directory. May be unset or +The current working directory. +May be unset or .Dv NULL if the shell doesn't know where it is. .It Ev REPLY @@ -1207,7 +1272,8 @@ Default parameter for the .Ic read command if no names are given. .It Ev TMPDIR -The directory shell temporary files are created in. If this parameter is not +The directory shell temporary files are created in. +If this parameter is not set, or does not contain the absolute path of a writable directory, temporary files are created in .Pa /tmp . @@ -1218,7 +1284,8 @@ on words starting with an unquoted .Ql ~ . The characters following the tilde, up to the first .Ql / , -if any, are assumed to be a login name. If the login name is empty, +if any, are assumed to be a login name. +If the login name is empty, .Ql + or .Ql - , @@ -1227,9 +1294,11 @@ the value of the .Ev PWD , or .Ev OLDPWD -parameter is substituted, respectively. Otherwise, the password file is +parameter is substituted, respectively. +Otherwise, the password file is searched for the login name, and the tilde expression is substituted with the -user's home directory. If the login name is not found in the password file or +user's home directory. +If the login name is not found in the password file or if any quoting or parameter substitution occurs in the login name, no substitution is performed. .Pp @@ -1256,30 +1325,34 @@ or .Ql * characters or .Dq [..] -sequences. Once brace expansion has been performed, the shell replaces file +sequences. +Once brace expansion has been performed, the shell replaces file name patterns with the sorted named of all the files that match the pattern -(if no files match, the word is left unchanged). The pattern elements have the -following meaning: +(if no files match, the word is left unchanged). +The pattern elements have the following meaning: .Bl -tag -width Ds .It Ic \&? Matches any single character. .It Ic \&* Matches any sequence of characters. .It Ic \&[ Ns No .. Ns Ic \&] -Matches any of the characters inside the brackets. Ranges of characters can be +Matches any of the characters inside the brackets. +Ranges of characters can be specified by separating two characters by a .Ql - (e.g., .Dq [a0-9] matches the letter .Dq a -or any digit). In order to represent itself, a +or any digit). +In order to represent itself, a .Ql - must either be quoted or the first or last character in the character list. Similarly, a .Ql \&] must be quoted or the first character in the list if it is to represent itself -instead of the end of the list. Also, a +instead of the end of the list. +Also, a .Ql ! appearing at the start of the list has special meaning (see below), so to represent itself it must be quoted or appear later in the list. @@ -1332,7 +1405,8 @@ expression) are not yet implemented. .Ss Input/output redirection When a command is executed, its standard input, standard output, and standard error (file descriptors 0, 1, and 2, respectively) are normally inherited from -the shell. Three exceptions to this are commands in pipelines, for which +the shell. +Three exceptions to this are commands in pipelines, for which standard input and/or standard output are those set up by the pipeline, asynchronous commands created when job control is disabled, for which standard input is initially set to be from @@ -1346,8 +1420,8 @@ If .Ar file does not exist, it is created; if it does exist, is a regular file and the .Ic noclobber -option is set, an error occurs; otherwise, the file is truncated. Note that this -means the command +option is set, an error occurs; otherwise, the file is truncated. +Note that this means the command .Ic cmd < foo > foo will open .Ar foo @@ -1366,7 +1440,8 @@ Same as .Ic \&> , except if .Ar file -exists it is appended to instead of being truncated. Also, the file is opened +exists it is appended to instead of being truncated. +Also, the file is opened in append mode, so writes always go to the end of the file (see .Fn open 2 ) . .It Ic \&< Ar file @@ -1383,8 +1458,10 @@ After reading the command line containing this kind of redirection (called a the shell copies lines from the command source into a temporary file until a line matching .Ar marker -is read. When the command is executed, standard input is redirected from the -temporary file. If +is read. +When the command is executed, standard input is redirected from the +temporary file. +If .Ar marker contains no quoted characters, the contents of the temporary file are processed as if enclosed in double quotes each time the command is executed, so @@ -1396,7 +1473,7 @@ escapes for .Ql ` , .Ql \e , and -.Dq \enewline . +.Ql \enewline . If multiple here documents are used on the same command line, they are saved in order. .It Ic \&<\&<\&- Ar marker @@ -1422,16 +1499,19 @@ except the operation is done on standard output. .Pp In any of the above redirections, the file descriptor that is redirected (i.e., standard input or standard output) can be explicitly given by preceding the -redirection with a single digit. Parameter, command, and arithmetic +redirection with a single digit. +Parameter, command, and arithmetic substitutions, tilde substitutions, and (if the shell is interactive) file name generation are all performed on the .Ar file , .Ar marker and .Ar fd -arguments of redirections. Note, however, that the results of any file name +arguments of redirections. +Note, however, that the results of any file name generation are only used if a single file is matched; if multiple files match, -the word with the expanded file name generation characters is used. Note +the word with the expanded file name generation characters is used. +Note that in restricted shells, redirections which can create files cannot be used. .Pp For simple-commands, redirections may appear anywhere in the command; for @@ -1440,7 +1520,8 @@ compound-commands .Ic if statements, etc. .Pc , -any redirections must appear at the end. Redirections are processed after +any redirections must appear at the end. +Redirections are processed after pipelines are created and in the order they are given, so .Pp .Ic cat /foo/bar 2\&>&1 \&> /dev/null \&| cat -n @@ -1535,7 +1616,8 @@ Arithmetic (bit-wise) .Tn NOT . .It Ic \&+\&+ Increment; must be applied to a parameter (not a literal or other expression). -The parameter is incremented by 1. When used as a prefix operator, the result +The parameter is incremented by 1. +When used as a prefix operator, the result is the incremented value of the parameter; when used as a postfix operator, the result is the original value of the parameter. .It Ic \&-\&- @@ -1544,8 +1626,8 @@ Similar to except the parameter is decremented by 1. .It Ic \&, Separates two arithmetic expressions; the left-hand side is evaluated first, -then the right. The result is the value of the expression on the right-hand -side. +then the right. +The result is the value of the expression on the right-hand side. .It Ic = Assignment; variable on the left is set to the value on the right. .It Xo Ic \&*= /= \&+= \&-= \&<\&<= @@ -1565,13 +1647,13 @@ is the same as .It Ic \&|\&| Logical .Tn OR ; -the result is 1 if either argument is non-zero, 0 if not. The right -argument is evaluated only if the left argument is zero. +the result is 1 if either argument is non-zero, 0 if not. +The right argument is evaluated only if the left argument is zero. .It Ic \&&\&& Logical .Tn AND ; -the result is 1 if both arguments are non-zero, 0 if not. The -right argument is evaluated only if the left argument is non-zero. +the result is 1 if both arguments are non-zero, 0 if not. +The right argument is evaluated only if the left argument is non-zero. .It Ic \&| Arithmetic (bit-wise) .Tn OR . @@ -1590,7 +1672,8 @@ Not equal; the result is 0 if both arguments are equal, 1 if not. Less than; the result is 1 if the left argument is less than the right, 0 if not. .It Ic \&<= \&>= \&> -Less than or equal, greater than or equal, greater than. See +Less than or equal, greater than or equal, greater than. +See .Ic \&< . .It Ic \&<\&< \&>\&> Shift left (right); the result is the left argument with its bits shifted left @@ -1599,8 +1682,8 @@ Shift left (right); the result is the left argument with its bits shifted left Addition, subtraction, multiplication, and division. .It Ic % Remainder; the result is the remainder of the division of the left argument by -the right. The sign of the result is unspecified if either argument is -negative. +the right. +The sign of the result is unspecified if either argument is negative. .It Xo Ao Ar arg1 Ac Ic \ \&? .Ao Ar arg2 Ac Ic \ \&: Ao Ar arg3 Ac .Xc @@ -1616,12 +1699,15 @@ Functions are defined using either Korn shell .Ic function Ar name syntax or the Bourne/POSIX shell .Fn name -syntax (see below for the difference between the two forms). Functions are like +syntax (see below for the difference between the two forms). +Functions are like .Li .-scripts -in that they are executed in the current environment. However, unlike +in that they are executed in the current environment. +However, unlike .Li .-scripts , shell arguments (i.e., positional parameters $1, $2, etc.) are never visible -inside them. When the shell is determining the location of a command, functions +inside them. +When the shell is determining the location of a command, functions are searched after special built-in commands, before regular and non-regular built-ins, and before the .Ev PATH @@ -1640,7 +1726,8 @@ may be used to create undefined functions; when an undefined function is executed, the shell searches the path specified in the .Ev FPATH parameter for a file with the same name as the function, which, if found, is -read and executed. If after executing the file the named function is found to +read and executed. +If after executing the file the named function is found to be defined, the function is executed; otherwise, the normal command search is continued (i.e., the shell searches the regular built-in command table and .Ev PATH ) . @@ -1658,24 +1745,28 @@ which can be set with .Ic typeset \&-ft and .Ic typeset \&-fx , -respectively. When a traced function is executed, the shell's +respectively. +When a traced function is executed, the shell's .Ic xtrace option is turned on for the function's duration; otherwise, the .Ic xtrace -option is turned off. The +option is turned off. +The .Dq export -attribute of functions is currently not used. In the original Korn shell, +attribute of functions is currently not used. +In the original Korn shell, exported functions are visible to shell scripts that are executed. .Pp Since functions are executed in the current shell environment, parameter assignments made inside functions are visible after the function completes. If this is not the desired effect, the .Ic typeset -command can be used inside a function to create a local parameter. Note that -special parameters (e.g., $$, $\&!) can't be scoped in this way. +command can be used inside a function to create a local parameter. +Note that special parameters (e.g., $$, $\&!) can't be scoped in this way. .Pp The exit status of a function is that of the last command executed in the -function. A function can be made to finish immediately using the +function. +A function can be made to finish immediately using the .Ic return command; this may also be used to explicitly specify the exit status. .Pp @@ -1703,12 +1794,13 @@ untouched, so using .Ic getopts inside a function interferes with using .Ic getopts -outside the function). In the future, the following differences will also be -added: +outside the function). +In the future, the following differences will also be added: .Bl -bullet -offset indent .It A separate trap/signal environment will be used during the execution of -functions. This will mean that traps set inside a function will not affect the +functions. +This will mean that traps set inside a function will not affect the shell's traps and signals that are not ignored in the shell (but may be trapped) will have their default effect in a function. .It @@ -1722,14 +1814,15 @@ The shell is intended to be compliant; however, in some cases, .Tn POSIX behaviour is contrary either to the original Korn shell behaviour or to user -convenience. How the shell behaves in these cases is determined by the state -of the +convenience. +How the shell behaves in these cases is determined by the state of the .Ic posix option .Pq Ic set Fl o Ic posix . If it is on, the .Tn POSIX -behaviour is followed; otherwise, it is not. The +behaviour is followed; otherwise, it is not. +The .Ic posix option is set automatically when the shell starts up if the environment contains the @@ -1755,15 +1848,16 @@ Occurrences of .Ic \e\&" inside double quoted .Ic `\&.\&.` -command substitutions. In +command substitutions. +In .Tn POSIX mode, the .Ic \e\&" is interpreted when the command is interpreted; in .Pf non- Tn POSIX mode, the -backslash is stripped before the command substitution is interpreted. For -example, +backslash is stripped before the command substitution is interpreted. +For example, .Ic echo \&"`echo \e\&"hi\e\&"`\&" produces .Dq \&"hi\&" @@ -1773,25 +1867,28 @@ mode, .Dq hi in .Pf non- Tn POSIX -mode. To avoid problems, use the +mode. +To avoid problems, use the .Ic $(...) form of command substitution. .It .Ic kill -l -output. In +output. +In .Tn POSIX mode, signal names are listed one per line; in .Pf non- Tn POSIX mode, -signal numbers, names and descriptions are printed in columns. In future, a new -option +signal numbers, names and descriptions are printed in columns. +In future, a new option .Po Fl v \ perhaps .Pc will be added to distinguish the two behaviours. .It .Ic fg -exit status. In +exit status. +In .Tn POSIX mode, the exit status is 0 if no errors occur; in .Pf non- Tn POSIX @@ -1809,18 +1906,20 @@ mode, options can start with either or .Ql + . .It -Brace expansion (also known as alternation). In +Brace expansion (also known as alternation). +In .Tn POSIX mode, brace expansion is disabled; in .Pf non- Tn POSIX -mode, brace expansion is enabled. Note that +mode, brace expansion is enabled. +Note that .Ic set Fl o Ic posix (or setting the .Ev POSIXLY_CORRECT parameter) automatically turns the .Ic braceexpand -option off, although it can be explicitly turned on later. +option off; however, it can be explicitly turned on later. .It .Ic set \&- . In @@ -1834,7 +1933,8 @@ options; in mode, it does. .It .Ic set -exit status. In +exit status. +In .Tn POSIX mode, the exit status of .Ic set @@ -1843,13 +1943,15 @@ is 0 if there are no errors; in mode, the exit status is that of any command substitutions performed in generating the .Ic set -command. For example, +command. +For example, .Ic set \&-\&- `false`; echo $? prints 0 in .Tn POSIX mode, 1 in .Pf non- Tn POSIX -mode. This construct is used in most shell scripts that use the old +mode. +This construct is used in most shell scripts that use the old .Xr getopt 1 command. .It @@ -1859,7 +1961,8 @@ Argument expansion of .Ic readonly , and .Ic typeset -commands. In +commands. +In .Tn POSIX mode, normal argument expansion is done; in .Pf non- Tn POSIX @@ -1867,7 +1970,8 @@ mode, field splitting, file globbing, brace expansion, and (normal) tilde expansion are turned off, while assignment tilde expansion is turned on. .It -Signal specification. In +Signal specification. +In .Tn POSIX mode, signals can be specified as digits, only if signal numbers match @@ -1877,13 +1981,15 @@ KILL=9, ALRM=14, and TERM=15); in .Pf non- Tn POSIX mode, signals can always be digits. .It -Alias expansion. In +Alias expansion. +In .Tn POSIX mode, alias expansion is only carried out when reading command words; in .Pf non- Tn POSIX mode, alias expansion is carried out on any -word following an alias that ended in a space. For example, the following +word following an alias that ended in a space. +For example, the following .Ic for loop .Pp @@ -1904,7 +2010,8 @@ in .Pf non- Tn POSIX mode. .It -Test. In +Test. +In .Tn POSIX mode, the expression .Ql Fl t @@ -1920,27 +2027,30 @@ test may be left out and defaults to 1). .El .Ss Command execution After evaluation of command-line arguments, redirections and parameter -assignments, the type of command is determined: a special built-in, a +assignments, the type of command is determined: a special built-in, a function, a regular built-in, or the name of a file to execute found using the .Ev PATH -parameter. The checks are made in the above order. Special built-in commands -differ from other commands in that the +parameter. +The checks are made in the above order. +Special built-in commands differ from other commands in that the .Ev PATH parameter is not used to find them, and an error during their execution can cause a non-interactive shell to exit and parameter assignments that are -specified before the command are kept after the command completes. Just to -confuse things, if the +specified before the command are kept after the command completes. +Just to confuse things, if the .Ic posix option is turned off (see .Ic set command below), some special commands are very special in that no field splitting, file globbing, brace expansion, nor tilde expansion is performed -on arguments that look like assignments. Regular built-in commands are -different only in that the +on arguments that look like assignments. +Regular built-in commands are different only in that the .Ev PATH parameter is not used to find them. .Pp -The original ksh and +The original +.Nm ksh +and .Tn POSIX differ somewhat in which commands are considered special or regular: @@ -1985,15 +2095,18 @@ The following described the special and regular built-in commands: .It Ic \&. Ar file Op Ar arg1 ... Execute the commands in .Ar file -in the current environment. The file is searched for in the directories of +in the current environment. +The file is searched for in the directories of .Ev PATH . If arguments are given, the positional parameters may be used to access them while .Ar file -is being executed. If no arguments are given, the positional parameters are +is being executed. +If no arguments are given, the positional parameters are those of the environment the command is used in. .It Ic \&: Op Ar ... -The null command. Exit status is set to zero. +The null command. +Exit status is set to zero. .It Xo Ic alias .Op Fl d | Ic +-t Op Fl r .Op Ic +-px @@ -2005,21 +2118,26 @@ The null command. Exit status is set to zero. .Xc Without arguments, .Ic alias -lists all aliases. For any name without a value, the existing alias is listed. +lists all aliases. +For any name without a value, the existing alias is listed. Any name with a value defines an alias (see .Sx Aliases above). .Pp -When listing aliases, one of two formats is used. Normally, aliases are listed -as +When listing aliases, one of two formats is used. +Normally, aliases are listed as .Ar name Ns No = Ar value , where .Ar value -is quoted. If options were preceded with +is quoted. +If options were preceded with .Ql + , -or a lone \&+ is given on the command line, only +or a lone +.Ql + +is given on the command line, only .Ar name -is printed. In addition, if the +is printed. +In addition, if the .Fl p option is used, each alias is prefixed with the string .Dq alias\ \& . @@ -2036,7 +2154,8 @@ with the export attribute (exporting an alias has no effect). The .Fl t option indicates that tracked aliases are to be listed/set (values specified on -the command line are ignored for tracked aliases). The +the command line are ignored for tracked aliases). +The .Fl r option indicates that all tracked aliases are to be reset. .Pp @@ -2047,11 +2166,11 @@ listed or set (see .Sx Tilde expansion above). .It Ic bg Op Ar job ... -Resume the specified stopped job(s) in the background. If no jobs are -specified, +Resume the specified stopped job(s) in the background. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic bind Op Fl m @@ -2088,7 +2207,8 @@ is set, it lists the search path for the directory containing .Ar dir . A .Dv NULL -path means the current directory. If +path means the current directory. +If .Ar dir is found in any component of the .Ev CDPATH @@ -2099,13 +2219,15 @@ If .Ar dir is missing, the home directory .Ev HOME -is used. If +is used. +If .Ar dir is .Ql - , the previous working directory is used (see .Ev OLDPWD -parameter). If the +parameter). +If the .Fl L option (logical path) is used or if the .Ic physical @@ -2115,13 +2237,15 @@ command below) isn't set, references to .Dq \&.\&. in .Ar dir -are relative to the path used to get to the directory. If the +are relative to the path used to get to the directory. +If the .Fl P option (physical path) is used or if the .Ic physical option is set, .Dq \&.\&. -is relative to the filesystem directory tree. The +is relative to the filesystem directory tree. +The .Ev PWD and .Ev OLDPWD @@ -2142,15 +2266,17 @@ directory. .Ar cmd is executed exactly as if .Ic command -had not been specified, with two exceptions. First, +had not been specified, with two exceptions. +First, .Ar cmd cannot be a shell function, and second, special built-in commands lose their specialness (i.e., redirection and utility errors do not cause the shell to -exit, and command assignments are not permanent). If the +exit, and command assignments are not permanent). +If the .Fl p option is given, a default search path is used instead of the current value of .Ev PATH -(the actual value of the default path is system dependent: on POSIXish +(the actual value of the default path is system dependent: on POSIXish systems, it is the value returned by .Ic getconf CS_PATH ) . .It Ic continue Op Ar level @@ -2168,7 +2294,8 @@ defaults to 1. .Op Ar arg ... .Xc Prints its arguments (separated by spaces) followed by a newline, to the -standard output. The newline is suppressed if any of the arguments contain the +standard output. +The newline is suppressed if any of the arguments contain the backslash sequence .Ql \ec . See the @@ -2177,7 +2304,8 @@ command below for a list of other backslash sequences that are recognized. .Pp The options are provided for compatibility with .Bx -shell scripts. The +shell scripts. +The .Fl n option suppresses the trailing newline, .Fl e @@ -2194,12 +2322,14 @@ The command is executed without forking, replacing the shell process. .Pp If no command is given except for I/O redirection, the I/O redirection is permanent and the shell is -not replaced. Any file descriptors which are opened or +not replaced. +Any file descriptors which are opened or .Xr dup 2 Ns No 'd in this way are made available to other executed commands (note that the Korn shell differs here: it does not pass on file descriptors greater than 2). .It Ic exit Op Ar status -The shell exits with the specified exit status. If +The shell exits with the specified exit status. +If .Ar status is not specified, the exit status is the current value of the .Ic \&? @@ -2207,9 +2337,9 @@ parameter. .It Xo Ic export Op Fl p .Op Ar parameter Ns Op \&= Ns Ar value .Xc -Sets the export attribute of the named parameters. Exported parameters are -passed in the environment to executed commands. If values are specified, the -named parameters are also assigned. +Sets the export attribute of the named parameters. +Exported parameters are passed in the environment to executed commands. +If values are specified, the named parameters are also assigned. .Pp If no parameters are specified, the names of all parameters with the export attribute are printed one per line, unless the @@ -2239,10 +2369,11 @@ are replaced with This command is usually accessed with the predefined .Ic alias r='fx -e -' . .It Ic fg Op Ar job ... -Resume the specified job(s) in the foreground. If no jobs are specified, +Resume the specified job(s) in the foreground. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic getopts Ar optstring name @@ -2253,9 +2384,11 @@ parameters, if no arguments are given) and to check for legal options. .Ar optstring contains the option letters that .Ic getopts -is to recognize. If a letter is followed by a colon, the option is expected to -have an argument. Options that do not take arguments may be grouped in a single -argument. If an option takes an argument and the option character is not the +is to recognize. +If a letter is followed by a colon, the option is expected to +have an argument. +Options that do not take arguments may be grouped in a single argument. +If an option takes an argument and the option character is not the last character of the argument it is found in, the remainder of the argument is taken to be the option's argument; otherwise, the next argument is the option's argument. @@ -2281,14 +2414,15 @@ mark or a colon is placed in .Ar name (indicating an illegal option or missing argument, respectively) and .Ev OPTAG -is set to the option character that caused the problem. An error message is -also printed to standard error if +is set to the option character that caused the problem. +An error message is also printed to standard error if .Ar optstring does not being with a colon. .Pp When the end of the options is encountered, .Ic getopts -exits with a non-zero exit status. Options end at the first (non-option +exits with a non-zero exit status. +Options end at the first (non-option argument) argument that does not start with a .Ql - , or when a @@ -2309,9 +2443,11 @@ may lead to unexpected results. .It Xo Ic hash Op Fl r .Op Ar name ... .Xc -Without arguments, any hashed executable command pathnames are listed. The +Without arguments, any hashed executable command pathnames are listed. +The .Fl r -option causes all hashed commands to be removed from the hash table. Each +option causes all hashed commands to be removed from the hash table. +Each .Ar name is searched as if it were a command name and added to the hash table if it is an executable command. @@ -2319,14 +2455,18 @@ an executable command. .Op Ar job ... .Xc Display information about the specified job(s); if no jobs are specified, all -jobs are displayed. The +jobs are displayed. +The .Fl n option causes information to be displayed only for jobs that have changed -state since the last notification. If the +state since the last notification. +If the .Fl l -option is used, the process ID of each process in a job is also listed. The +option is used, the process ID of each process in a job is also listed. +The .Fl p -option causes only the process group of each job to be printed. See +option causes only the process group of each job to be printed. +See .Sx Job control below for the format of .Ar job @@ -2339,10 +2479,12 @@ and the displayed job. .Ar pgrp No } Ar ... .Xc Send the specified signal to the specified jobs, process IDs, or process -groups. If no signal is specified, the +groups. +If no signal is specified, the .Dv TERM -signal is sent. If a job is specified, the signal is sent to the job's -process group. See +signal is sent. +If a job is specified, the signal is sent to the job's process group. +See .Sx Job control below for the format of .Ar job . @@ -2359,9 +2501,11 @@ a short description of them are printed. .Xc .Ic print prints its arguments on the standard output, separated by spaces and -terminated with a newline. The +terminated with a newline. +The .Fl n -option suppresses the newline. By default, certain C escapes are translated. +option suppresses the newline. +By default, certain C escapes are translated. These include .Ql \eb , .Ql \ef , @@ -2382,7 +2526,8 @@ option. .Ql \e expansion may be inhibited with the .Fl r -option. The +option. +The .Fl s option prints to the history file instead of standard output, the .Fl u @@ -2407,11 +2552,13 @@ command, which does not process .Ql \e sequences unless the .Fl e -option is given. As above, the +option is given. +As above, the .Fl n option suppresses the trailing newline. .It Ic pwd Op Fl LP -Print the present working directory. If the +Print the present working directory. +If the .Fl L option is used or if the .Ic physical @@ -2419,7 +2566,8 @@ option (see .Ic set command below) isn't set, the logical path is printed (i.e., the path used to .Ic cd -to the current directory). If the +to the current directory). +If the .Fl P option (physical path) is used or if the .Ic physical @@ -2434,17 +2582,19 @@ using the .Ev IFS parameter (see .Sx Substitution -above), and assigns each field to the specified parameters. If there are more -parameters than fields, the extra parameters are set to +above), and assigns each field to the specified parameters. +If there are more parameters than fields, the extra parameters are set to .Dv NULL , or alternatively, if there are more fields than parameters, the last parameter -is assigned the remaining fields (inclusive of any separating spaces). If no -parameters are specified, the +is assigned the remaining fields (inclusive of any separating spaces). +If no parameters are specified, the .Ev REPLY -parameter is used. If the input line ends in a backslash and the +parameter is used. +If the input line ends in a backslash and the .Fl r option was not used, the backslash and the newline are stripped and more input -is read. If no input is read, +is read. +If no input is read, .Ic read exits with a non-zero status. .Pp @@ -2461,7 +2611,8 @@ options cause input to be read from file descriptor .Ar n or the current co-process (see .Sx Co-processes -above for comments on this), respectively. If the +above for comments on this), respectively. +If the .Fl s option is used, input is saved to the history file. .It Xo Ic readonly Op Fl p @@ -2469,8 +2620,10 @@ option is used, input is saved to the history file. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Sets the read-only attribute of the named parameters. If values are given, -parameters are set to them before setting the attribute. Once a parameter is +Sets the read-only attribute of the named parameters. +If values are given, +parameters are set to them before setting the attribute. +Once a parameter is made read-only, it cannot be unset and its value cannot be changed. .Pp If no parameters are specified, the names of all parameters with the read-only @@ -2487,8 +2640,8 @@ script, with exit status .Ar status . If no .Ar status -is given, the exit status of the last executed command is used. If used -outside of a function or +is given, the exit status of the last executed command is used. +If used outside of a function or .Ic \&. script, it has the same effect as .Ic exit . @@ -2540,7 +2693,8 @@ the rest are left untouched. All new parameters are created with the export attribute. .It Fl b Ic notify Print job notification messages asynchronously, instead of just before the -prompt. Only used if job control is enabled +prompt. +Only used if job control is enabled .Pq Fl m . .It Fl C Ic noclobber Prevent @@ -2554,7 +2708,8 @@ must be used to force an overwrite Exit (after executing the .Dv ERR trap) as soon as an error occurs or a command fails (i.e., exits with a -non-zero status). This does not apply to commands whose exit status is +non-zero status). +This does not apply to commands whose exit status is explicitly tested by a shell construct such as .Ic if , .Ic until , @@ -2568,34 +2723,39 @@ Do not expand file name patterns. .It Fl h Ic trackall Create tracked aliases for all executed commands (see .Sx Aliases -above). Enabled by default for non-interactive shells. +above). +Enabled by default for non-interactive shells. .It Fl i Ic interactive -Enable interactive mode. This can only be set/unset when the shell is invoked. +Enable interactive mode. +This can only be set/unset when the shell is invoked. .It Fl k Ic keyword Parameter assignments are recognized anywhere in a command. .It Fl l Ic login -The shell is a login shell. This can only be set/unset when the shell is -invoked (see +The shell is a login shell. +This can only be set/unset when the shell is invoked (see .Sx Shell startup above). .It Fl m Ic monitor Enable job control (default for interactive shells). .It Fl n lc noexec -Do not execute any commands. Useful for checking the syntax of scripts +Do not execute any commands. +Useful for checking the syntax of scripts (ignored if interactive). .It Fl p Ic privileged Set automatically if, when the shell starts, the read UID or GID does not match -the effective UID (EUID) or GID (EGID), respectively. See +the effective UID (EUID) or GID (EGID), respectively. +See .Sx Shell startup above for a description of what this means. .It Fl r Ic restricted -Enable restricted mode. This option can only be used when the shell is invoked. +Enable restricted mode. +This option can only be used when the shell is invoked. See .Sx Shell startup above for a description of what this means. .It Fl s Ic stdin -If used where the shell is invoked, commands are read from standard input. Set -automatically if the shell is invoked with no arguments. +If used where the shell is invoked, commands are read from standard input. +Set automatically if the shell is invoked with no arguments. .Pp When .Fl s @@ -2633,13 +2793,15 @@ must be used. .It Ic nohup Do not kill running jobs with a .Dv HUP -signal when a login shell exists. Currently set by default, but this will +signal when a login shell exists. +Currently set by default, but this will change in the future to be compatible with the original Korn shell (which doesn't have this option, but does send the .Dv HUP signal). .It Ic nolog -No effect. In the original Korn shell, this prevents function definitions from +No effect. +In the original Korn shell, this prevents function definitions from being stored in the history file. .It Ic physical Causes the @@ -2654,9 +2816,9 @@ directories instead of .Dq logical directories (i.e., the shell handles .Dq \&.\&. , -which allows the user to be oblivious of symbolic links to directories). Clear -by default. Note that setting this option does not affect the current value of -the +which allows the user to be oblivious of symbolic links to directories). +Clear by default. +Note that setting this option does not affect the current value of the .Ev PWD parameter; only the .Ic cd @@ -2670,13 +2832,15 @@ commands above for more details. .It Ic posix Enable .Tn POSIX -mode. See +mode. +See .Sx POSIX mode above. .It Ic vi Enable vi-like command-line editing (interactive shells only). .It Ic viraw -No effect. In the original Korn shell, unless +No effect. +In the original Korn shell, unless .Ic viraw was set, the vi command-line mode would let the tty driver do the work until .Tn ESC @@ -2696,7 +2860,8 @@ In vi command-line editing, do command and file name completion when tab (^I) is entered in insert mode. .El .Pp -These options can also be used upon invocation of the shell. The current set of +These options can also be used upon invocation of the shell. +The current set of options (with single letter names) can be found in the parameter .Dv \&- . .Ic set Fl o @@ -2705,11 +2870,12 @@ with no option name will list all the options and whether each is on or off; will print the long names of all options that are currently on. .Pp Remaining arguments, if any, are positional parameters and are assigned, in -order, to the positional parameters (i.e., $1, $2, etc.). If options end with +order, to the positional parameters (i.e., $1, $2, etc.). +If options end with .Ql -- -and there are no remaining arguments, all positional parameters are cleared. If -no options or arguments are given, the values of all names are printed. For -unknown historical reasons, a lone +and there are no remaining arguments, all positional parameters are cleared. +If no options or arguments are given, the values of all names are printed. +For unknown historical reasons, a lone .Ql - option is treated specially -- it clears both the .Fl x @@ -2732,15 +2898,18 @@ defaults to 1. evaluates the .Ar expression and returns zero status if true, 1 status if false, or greater than 1 if there -was an error. It is normally used as the condition command of +was an error. +It is normally used as the condition command of .Ic if and .Ic while -statements. The following basic expressions are available: +statements. +The following basic expressions are available: .Bl -tag -width 17n .It Ar str .Ar str -has non-zero length. Note that there is the potential for problems if +has non-zero length. +Note that there is the potential for problems if .Ar str turns out to be an operator (e.g., .Fl r ) . @@ -2816,8 +2985,8 @@ Shell .Ar option is set (see .Ic set -command above for a list of options). As a non-standard extension, if the -option starts with a +command above for a list of options). +As a non-standard extension, if the option starts with a .Ql ! , the test is negated; the test always fails if .Ar option @@ -2845,7 +3014,8 @@ is the same file as second .It Fl t Op Ar fd File descriptor .Ar fd -is a tty device. If the +is a tty device. +If the .Ic posix option is not set, .Ar fd @@ -2906,7 +3076,8 @@ is a file descriptor number), the .Ic test command will attempt to fake it for all tests that operate on files (except the .Fl e -test). For example, +test). +For example, .Ic \&[ -w /dev/fd/2 \&] tests if file descriptor 2 is writable. .Pp @@ -2969,7 +3140,8 @@ or .Dv ALRM ) or the number of the signal (see .Ic kill -l -command above). There are two special signals: +command above). +There are two special signals: .Dv EXIT (also known as 0), which is executed when the shell is about to exit, and .Dv ERR , @@ -2982,7 +3154,8 @@ option were see -- see .Ic set command above). .Dv EXIT -handlers are executed in the environment of the last executed command. Note +handlers are executed in the environment of the last executed command. +Note that for non-interactive shells, the trap handler cannot be changed for signals that were ignored when the shell started. .Pp @@ -3013,7 +3186,8 @@ A command that exits with a zero value. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Display or set parameter attributes. With no +Display or set parameter attributes. +With no .Ar name arguments, parameter attributes are displayed; if no options are used, the current attributes of all parameters are printed as @@ -3031,7 +3205,8 @@ arguments are given, the attributes of the named parameters are set .Pq Ic \&- or cleared .Pq Ic \&+ . -Values for parameters may optionally be specified. If +Values for parameters may optionally be specified. +If .Ic typeset is used inside a function, any newly created parameters are local to the function. @@ -3040,7 +3215,8 @@ When .Fl f is used, .Ic typeset -operates on the attributes of functions. As with parameters, if no +operates on the attributes of functions. +As with parameters, if no .Ar name Ns s are given, functions are listed with their values (i.e., definitions) unless options are introduced with @@ -3050,22 +3226,27 @@ in which case only the function names are reported. .It Fl L Ns Ar n Left justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Leading whitespace (and zeros, if used with the +assigned value) is used. +Leading whitespace (and zeros, if used with the .Fl Z -option) is stripped. If necessary, values are either truncated or space padded +option) is stripped. +If necessary, values are either truncated or space padded to fit the field width. .It Fl R Ns Ar n Right justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Trailing whitespace is stripped. If necessary, values -are either stripped of leading characters or space padded to make them fit the -field width. +assigned value) is used. +Trailing whitespace is stripped. +If necessary, values are either stripped of leading characters or space +padded to make them fit the field width. .It Fl Z Ns Ar n Zero fill attribute. If not combined with .Fl L , @@ -3076,19 +3257,23 @@ except zero padding is used instead of space padding. Integer attribute. .Ar n specifies the base to use when displaying the integer (if not specified, the -base given in the first assignment is used). Parameters with this attribute may +base given in the first assignment is used). +Parameters with this attribute may be assigned values containing arithmetic expressions. .It Fl U -Unsigned integer attribute. Integers are printed as unsigned values (only +Unsigned integer attribute. +Integers are printed as unsigned values (only useful when combined with the .Fl i -option). This option is not in the original Korn shell. +option). +This option is not in the original Korn shell. .It Fl f -Function mode. Display or set functions and their attributes, instead of -parameters. +Function mode. +Display or set functions and their attributes, instead of parameters. .It Fl l -Lower case attribute. All upper case characters in values are converted to -lower case. (In the original Korn shell, this parameter meant +Lower case attribute. +All upper case characters in values are converted to lower case. +(In the original Korn shell, this parameter meant .Dq long integer when used with the .Fl i @@ -3097,52 +3282,63 @@ option.) Print complete .Ic typeset commands that can be used to re-create the attributes (but not the values) or -parameters. This is the default action (option exists for ksh93 compatibility). +parameters. +This is the default action (option exists for ksh93 compatibility). .It Fl r -Read-only attribute. Parameters with this attribute may not be assigned to or -unset. Once this attribute is set, it can not be turned off. +Read-only attribute. +Parameters with this attribute may not be assigned to or unset. +Once this attribute is set, it can not be turned off. .It Fl t -Tag attribute. Has no meaning to the shell; provided for application use. +Tag attribute. +Has no meaning to the shell; provided for application use. .Pp For functions, .Fl t -is the trace attribute. When functions with the trace attribute are executed, -the +is the trace attribute. +When functions with the trace attribute are executed, the .Ic xtrace .Pq Fl x shell option is temporarily turned on. .It Fl u -Upper case attribute. All lower case characters in values are converted to -upper case. (In the original Korn shell, this parameter meant +Upper case attribute. +All lower case characters in values are converted to upper case. +(In the original Korn shell, this parameter meant .Dq unsigned integer when used with the .Fl i option, which meant upper case letters would never be used for bases greater -than 10. See the +than 10. +See the .Fl U option.) .Pp For functions, .Fl u -is the undefined attribute. See +is the undefined attribute. +See .Sx Functions above for the implications of this. .It Fl x -Export attribute. Parameters (or functions) are placed in the environment of -any executed commands. Exported functions are not yet implemented. +Export attribute. +Parameters (or functions) are placed in the environment of +any executed commands. +Exported functions are not yet implemented. .El .It Xo Ic ulimit Op Fl acdfHlmnpsStvw .Op Ar value .Xc -Display or set process limits. If no options are used, the file size limit +Display or set process limits. +If no options are used, the file size limit .Pq Fl f is assumed. .Ar value , if specified, may be either an arithmetic expression or the word .Dq unlimited . The limits affect the shell and any processes created by the shell after a -limit is imposed. Note that some systems may not allow limits to be increased -once they are set. Also note that the types of limits available are system +limit is imposed. +Note that some systems may not allow limits to be increased +once they are set. +Also note that the types of limits available are system dependent -- some systems have only the .Fl f limit. @@ -3229,9 +3425,11 @@ and is equivalent (on most systems) to the octal mask .It Xo Ic unalias Op Fl adt .Op Ar name1 ... .Xc -The aliases for the given names are removed. If the +The aliases for the given names are removed. +If the .Fl a -option is used, all aliases are removed. If the +option is used, all aliases are removed. +If the .Fl t or .Fl d @@ -3250,7 +3448,8 @@ or functions The exit status is non-zero if any of the parameters were already unset, zero otherwise. .It Ic wait Op Ar job ... -Wait for the specified job(s) to finish. The exit status of +Wait for the specified job(s) to finish. +The exit status of .Ic wait is that of the last specified job; if the last job is killed by a signal, the exit status is 128 + the number of the signal (see @@ -3258,7 +3457,8 @@ exit status is 128 + the number of the signal (see above); if the last specified job can't be found (because it never existed, or had already finished), the exit status of .Ic wait -is 127. See +is 127. +See .Sx Job control below for the format of .Ar job . @@ -3273,7 +3473,8 @@ signal is received. If no jobs are specified, .Ic wait waits for all currently running jobs (if any) to finish and exits with a zero -status. If job monitoring is enabled, the completion status of jobs is printed +status. +If job monitoring is enabled, the completion status of jobs is printed (this is not the case when jobs are explicitly specified). .It Xo Ic whence Op Fl pv .Op Ar name ... @@ -3281,11 +3482,13 @@ status. If job monitoring is enabled, the completion status of jobs is printed For each .Ar name , the type of command is listed (reserved word, built-in, alias, -function, tracked alias, or executable). If the +function, tracked alias, or executable). +If the .Fl p option is used, a path search is performed even if .Ar name -is a reserved word, alias, etc. Without the +is a reserved word, alias, etc. +Without the .Fl v option, .Ic whence @@ -3293,7 +3496,8 @@ is similar to .Ic command Fl v except that .Ic whence -will find reserved words and won't print aliases as alias commands. With the +will find reserved words and won't print aliases as alias commands. +With the .Fl v option, .Ic whence @@ -3310,17 +3514,19 @@ status is non-zero. .El .Ss Job control Job control refers to the shell's ability to monitor and control jobs, which -are processes or groups of processes created for commands or pipelines. At a -minimum, the shell keeps track of the status of the background (i.e., +are processes or groups of processes created for commands or pipelines. +At a minimum, the shell keeps track of the status of the background (i.e., asynchronous) jobs that currently exist; this information can be displayed using the .Ic jobs -commands. If job control is fully enabled (using +commands. +If job control is fully enabled (using .Ic set Fl m or .Ic set Fl o Ic monitor ) , as it is for interactive shells, the processes of a job are placed in their -own process group. Foreground jobs can be stopped by typing the suspend +own process group. +Foreground jobs can be stopped by typing the suspend character from the terminal (normally ^Z), jobs can be restarted in either the foreground or background using the .Ic fg @@ -3335,11 +3541,12 @@ commands like .Ic read cannot be. .Pp -When a job is created, it is assigned a job number. For interactive shells, -this number is printed inside +When a job is created, it is assigned a job number. +For interactive shells, this number is printed inside .Dq \&[..\&] , followed by the process IDs of the processes in the job when an asynchronous -command is run. A job may be referred to in +command is run. +A job may be referred to in .Ic bg , .Ic fg , .Ic jobs , @@ -3412,12 +3619,14 @@ The job was stopped by the indicated .It Ar signal-description Op Dq core dumped The job was killed by a signal (e.g., memory fault, hangup, etc.; use .Ic kill -l -for a list of signal descriptions). The +for a list of signal descriptions). +The .Dq core dumped message indicates the process created a core file. .El .It Ar command -is the command that created the process. If there are multiple processes in +is the command that created the process. +If there are multiple processes in the job, each process will have a line showing its .Ar command and possibly its @@ -3430,10 +3639,12 @@ state, the shell warns the user that there are stopped jobs and does not exit. If another attempt is immediately made to exit the shell, the stopped jobs are sent a .Dv HUP -signal and the shell exits. Similarly, if the +signal and the shell exits. +Similarly, if the .Ic nohup option is not set and there are running jobs when an attempt is made to exit -a login shell, the shell warns the user and does not exit. If another attempt +a login shell, the shell warns the user and does not exit. +If another attempt is immediately made to exit the shell, the running jobs are sent a .Dv HUP signal and the shell exits. @@ -3490,7 +3701,8 @@ is implemented as a run-time option of with only those .Nm ksh features whose syntax or semantics are incompatible with a traditional Bourne -shell disabled. Since this leaves some +shell disabled. +Since this leaves some .Nm ksh extensions exposed, caution should be used where backwards compatibility with traditional Bourne or @@ -3499,7 +3711,8 @@ compliant shells is an issue. .Sh BUGS Any bugs in .Nm pdksh -should be reported to pdksh@cs.mun.ca. Please include the version of +should be reported to pdksh@cs.mun.ca. +Please include the version of .Nm pdksh .Po .Ic echo $KSH_VERSION @@ -3516,7 +3729,8 @@ and a copy of your .Pa config.h (the file generated by the .Pa configure -script). New version of +script). +New versions of .Nm pdksh can be obtained from ftp://ftp.cs.mun.ca/pub/pdksh. .Pp @@ -3529,11 +3743,13 @@ I'm aware of this and there is no need to report it. .Sh AUTHORS This shell is based on the public domain 7th edition Bourne shell clone by Charles Forsyth and parts of the BRL shell by Doug A. Gwyn, Doug Kingston, -Ron Natalie, Arnold Robbins, Lou Salkind, and others. The first release of +Ron Natalie, Arnold Robbins, Lou Salkind, and others. +The first release of .Nm pdksh was created by Eric Gisin, and it was subsequently maintained by John R. MacMillan (change!john@sq.sq.com) and Simon J. Gerraty (sjg@zen.void.oz.au). -The current maintainer is Michael Rendell (michael@cs.mun.ca). The +The current maintainer is Michael Rendell (michael@cs.mun.ca). +The .Pa CONTRIBUTORS file in the source distribution contains a more complete list of people and their part in the shell's development. diff --git a/bin/ksh/sh.1tbl b/bin/ksh/sh.1tbl index 7e7a8a76f60..25787a52e3e 100644 --- a/bin/ksh/sh.1tbl +++ b/bin/ksh/sh.1tbl @@ -1,4 +1,4 @@ -.\" $OpenBSD: sh.1tbl,v 1.16 1999/07/05 19:50:53 aaron Exp $ +.\" $OpenBSD: sh.1tbl,v 1.17 2000/03/17 18:15:16 aaron Exp $ .\" .\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -79,8 +79,10 @@ If neither the nor the .Fl s option is specified, the first non-option argument specifies the name -of a file the shell reads commands from. If there are no non-option -arguments, the shell reads commands from the standard input. The name of +of a file the shell reads commands from. +If there are no non-option +arguments, the shell reads commands from the standard input. +The name of the shell (i.e., the contents of $0) is determined as follows: if the .Fl c option is used and there is a non-option argument, it is used as the name; @@ -92,8 +94,8 @@ A shell is if the .Fl i option is used or if both standard input and standard error are attached -to a tty. An interactive shell has job control enabled (if available), -ignores the +to a tty. +An interactive shell has job control enabled (if available), ignores the .Dv SIGINT , .Dv SIGQUIT , and @@ -169,9 +171,11 @@ A privileged shell does not process .Pa $HOME/.profile nor the .Ev ENV -parameter (see below). Instead, the file +parameter (see below). +Instead, the file .Pa /etc/suid_profile -is processed. Clearing the privileged option causes the shell to set +is processed. +Clearing the privileged option causes the shell to set its effective user ID (group ID) to its real user ID (group ID). .Pp If the basename of the name the shell is called with (i.e., argv[0]) @@ -194,7 +198,8 @@ after any profiles are processed), its value is subjected to parameter, command, arithmetic, and tilde .Pq Sq \&~ substitution and the resulting file -(if any) is read and executed. If the +(if any) is read and executed. +If the .Ev ENV parameter is not set (and not .Dv NULL ) @@ -207,7 +212,8 @@ mentioned substitutions have been performed). .Pp The exit status of the shell is 127 if the command file specified on the command line could not be opened, or non-zero if a fatal syntax error -occurred during the execution of a script. In the absence of fatal errors, +occurred during the execution of a script. +In the absence of fatal errors, the exit status is that of the last command executed, or zero, if no command is executed. .Ss Command syntax @@ -225,8 +231,8 @@ and .Ql \&) .Pc . Aside from delimiting words, spaces and tabs are ignored, while newlines -usually delimit commands. The meta-characters are used in building the -following tokens: +usually delimit commands. +The meta-characters are used in building the following tokens: .Ql < , .Ql <& , .Ql << , @@ -260,7 +266,8 @@ or in groups using double .Pq Sq \&" or single .Pq Sq \&' -quotes. Note that the following characters are also treated specially by the +quotes. +Note that the following characters are also treated specially by the shell and must be quoted if they are to represent themselves: .Ql \e , .Ql \&" , @@ -331,8 +338,10 @@ input/output redirections (see .Sx Input/output redirections below), and command words; the only restriction is that parameter assignments come -before any command words. The command words, if any, define the command -that is to be executed and its arguments. The command may be a shell built-in +before any command words. +The command words, if any, define the command +that is to be executed and its arguments. +The command may be a shell built-in command, a function or an external command (i.e., a separate executable file that is located using the .Ev PATH @@ -346,7 +355,8 @@ this is related to the status returned by be executed, the exit status is 126); the exit status of other command constructs (built-in commands, functions, compound-commands, pipelines, lists, etc.) are all well-defined and are described where the construct is -described. The exit status of a command consisting only of parameter +described. +The exit status of a command consisting only of parameter assignments is that of the last command substitution performed during the parameter assignment or 0 is there were no command substitutions. .Pp @@ -355,8 +365,9 @@ Commands can be chained together using the token to form pipelines, in which the standard output of each command but the last is piped (see .Xr pipe 2 ) -to the standard input of the following command. The exit status of a pipeline -is that of its last command. A pipeline may be prefixed by the +to the standard input of the following command. +The exit status of a pipeline is that of its last command. +A pipeline may be prefixed by the .Ql ! reversed word which causes the exit status of the pipeline to be logically complemented: if the original status was 0 the complemented status will be 1; @@ -387,18 +398,20 @@ is non-zero. .Ql && and .Ql || -have equal precedence which is higher that that of +have equal precedence which is higher than that of .Ql & , .Ql |& and .Ql \&; , -which also have equal precedence. The +which also have equal precedence. +The .Ql & token causes the preceding command to be executed asynchronously; that is, the shell starts the command but does not wait for it to complete (the shell does keep track of the status of asynchronous commands, see .Sx Job control -below). When an asynchronous command is started when job control is disabled +below). +When an asynchronous command is started when job control is disabled (i.e., in most scripts), the command is started with signals .Dv SIGINT and @@ -418,7 +431,8 @@ or The exit status of a list is that of the last command executed, with the exception of asynchronous lists, for which the exit status is 0. .Pp -Compound commands are created using the following reserved words. These words +Compound commands are created using the following reserved words. +These words are only recognized if they are unquoted and if they are used as the first word of a command (i.e., they can't be preceded by parameter assignments or redirections): @@ -435,7 +449,8 @@ elif for time then } .Sy Note: Some shells (but not this one) execute control structure commands in a subshell when one or more of their file descriptors are redirected, so any -environment changes inside them may fail. To be portable, the +environment changes inside them may fail. +To be portable, the .Ic exec statement should be used instead to redirect file descriptors before the control structure. @@ -443,7 +458,8 @@ control structure. In the following compound command descriptions, command lists (denoted as .Em list ) that are followed by reserved words must end with a semicolon, a newline, or -a (syntactically correct) reserved word. For example, +a (syntactically correct) reserved word. +For example, .Pp .Bl -inset -indent -compact .It Ic { echo foo; echo bar; } @@ -462,12 +478,14 @@ is not. .It Ic \&( Ar list Ic \&) Execute .Ar list -in a subshell. There is no implicit way to pass environment changes from a +in a subshell. +There is no implicit way to pass environment changes from a subshell back to its parent. .It Ic \&{ Ar list Ic \&} Compound construct; .Ar list -is executed, but not in a subshell. Note that +is executed, but not in a subshell. +Note that .Ic \&{ and .Ic \&} @@ -487,19 +505,21 @@ against the specified .Ar pattern Ns s ; the .Ar list -associated with the first successfully matched pattern is executed. Patterns -used in +associated with the first successfully matched pattern is executed. +Patterns used in .Ic case statements are the same as those used for file name patterns except that the restrictions regarding .Ql \&. and .Ql / -are dropped. Note that any unquoted space before and after a pattern is -stripped; any space with a pattern must be quoted. Both the word and the +are dropped. +Note that any unquoted space before and after a pattern is +stripped; any space with a pattern must be quoted. +Both the word and the patterns are subject to parameter, command, and arithmetic substitution, as -well as tilde substitution. For historical reasons, open and close braces -may be used instead of +well as tilde substitution. +For historical reasons, open and close braces may be used instead of .Ic in and .Ic esac @@ -522,11 +542,12 @@ in the specified word list, the parameter .Ar name is set to the word and .Ar list -is executed. If +is executed. +If .Ic in is not used to specify a word list, the positional parameters ($1, $2, etc.) -are used instead. For historical reasons, open and close braces may be used -instead of +are used instead. +For historical reasons, open and close braces may be used instead of .Ic do and .Ic done @@ -555,8 +576,8 @@ is executed; otherwise, the .Ar list following the .Ic elif , -if any, is executed with similar consequences. If all the lists following -the +if any, is executed with similar consequences. +If all the lists following the .Ic if and .Ic elif Ns s @@ -564,7 +585,8 @@ fail (i.e., exit with non-zero status), the .Ar list following the .Ic else -is executed. The exit status of an +is executed. +The exit status of an .Ic if statement is that of non-conditional .Ar list @@ -584,10 +606,11 @@ is non-zero. .Xc A .Ic while -is a pre-checked loop. Its body is executed as often as the exit status of -the first +is a pre-checked loop. +Its body is executed as often as the exit status of the first .Ar list -is zero. The exit status of a +is zero. +The exit status of a .Ic while statement is the last exit status of the .Ar list @@ -599,7 +622,8 @@ Defines the function .Ar name (see .Sx Functions -below). Note that redirections specified after a function definition are +below). +Note that redirections specified after a function definition are performed whenever the function is executed, not when the function definition is executed. .It Ar name Ic () Ar command @@ -611,15 +635,18 @@ below). .El .Ss Quoting Quoting is used to prevent the shell from treating characters or words -specially. There are three methods of quoting. First, +specially. +There are three methods of quoting. +First, .Ql \e quotes the following character, unless it is at the end of a line, in which case both the .Ql \e -and the newline are stripped. Second, a single quote +and the newline are stripped. +Second, a single quote .Pq Sq ' -quotes everything up to the next single quote (this may span lines). Third, -a double quote +quotes everything up to the next single quote (this may span lines). +Third, a double quote .Pq Sq \&" quotes all characters, except .Ql $ , @@ -632,7 +659,8 @@ and .Ql ` inside double quotes have their usual meaning (i.e., parameter, command or arithmetic substitution) except no field splitting is carried out on the -results of double-quoted substitutions. If a +results of double-quoted substitutions. +If a .Ql \e inside a double-quoted string is followed by .Ql \e , @@ -655,13 +683,15 @@ below for a special rule regarding sequences of the form .Ss Aliases There are two types of aliases: normal command aliases and tracked aliases. Command aliases are normally used as a short hand for a long or often used -command. The shell expands command aliases (i.e., substitutes the alias name -for its value) when it reads the first word of a command. An expanded alias -is re-processed to check for more aliases. If a command alias ends in a -space or tab, the following word is also checked for alias expansion. The -alias expansion process stops when a word that is not an alias is found, when -a quoted word is found or when an alias word that is currently being expanded -is found. +command. +The shell expands command aliases (i.e., substitutes the alias name +for its value) when it reads the first word of a command. +An expanded alias is re-processed to check for more aliases. +If a command alias ends in a +space or tab, the following word is also checked for alias expansion. +The alias expansion process stops when a word that is not an alias is found, +when a quoted word is found or when an alias word that is currently being +expanded is found. .Pp The following command aliases are defined automatically by the shell: .Pp @@ -673,22 +703,26 @@ The following command aliases are defined automatically by the shell: .El .Pp Tracked aliases allow the shell to remember where it found a particular -command. The first time the shell does a path search for a command that is -marked as a tracked alias, it saves the full path of the command. The next +command. +The first time the shell does a path search for a command that is +marked as a tracked alias, it saves the full path of the command. +The next time the command is executed, the shell checks the saved path to see that it -is still valid, and if so, avoids repeating the path search. Tracked aliases -can be listed and created using +is still valid, and if so, avoids repeating the path search. +Tracked aliases can be listed and created using .Ic alias -t . Note that changing the .Ev PATH -parameter clears the saved paths for all tracked aliases. If the +parameter clears the saved paths for all tracked aliases. +If the .Ic trackall option is set (i.e., .Ic set Fl o Ic trackall or .Ic set Fl h ) , -the shell tracks all commands. This option is set automatically for -non-interactive shells. For interactive shells, only the following commands are +the shell tracks all commands. +This option is set automatically for non-interactive shells. +For interactive shells, only the following commands are automatically tracked: .Ic cat , cc , chmod , cp , .Ic date , ed , emacs , grep , @@ -699,14 +733,16 @@ and .Ic who . .Ss Substitution The first step the shell takes in executing a simple-command is to perform -substitutions on the words of the command. There are three kinds of -substitution: parameter, command, and arithmetic. Parameter substitutions, +substitutions on the words of the command. +There are three kinds of +substitution: parameter, command, and arithmetic. +Parameter substitutions, which are described in detail in the next section, take the form -.Ic $name +.Ic $ Ns Ar name or -.Ic ${...} ; +.Ic ${ Ns Ar ... Ns Ic \&} ; command substitutions take the form -.Ic $( Ns Ar command Ns Ic ) +.Ic $( Ns Ar command Ns Ic \&) or .Ic ` Ns Ar command Ns Ic ` ; and arithmetic substitutions take the form @@ -716,7 +752,8 @@ If a substitution appears outside of double quotes, the results of the substitution are generally subject to word or field splitting according to the current value of the .Ev IFS -parameter. The +parameter. +The .Ev IFS parameter specifies a list of characters which are used to break a string up into several words; any characters from the set space, tab, and newline that @@ -729,7 +766,8 @@ Sequences of one or more whitespace characters, in combination with zero or no .Pf non- Ev IFS whitespace -characters, delimit a field. As a special case, leading and trailing +characters, delimit a field. +As a special case, leading and trailing .Ev IFS whitespace is stripped (i.e., no leading or trailing empty field is created by it); leading or trailing @@ -756,7 +794,8 @@ string, no field splitting is done; if the parameter is unset, the default value of space, tab, and newline is used. .Pp Also, note that the field splitting applies only to the immediate result of -the substitution. Using the previous example, the substitution for $VAR:E +the substitution. +Using the previous example, the substitution for $VAR:E results in the fields: .Dq A , .Dq B , @@ -779,8 +818,9 @@ The results of substitution are, unless otherwise specified, also subject to brace expansion and file name expansion (see the relevant sections below). .Pp A command substitution is replaced by the output generated by the specified -command, which is run in a subshell. For -.Ic $( Ns Ar command Ns Ic ) +command, which is run in a subshell. +For +.Ic $( Ns Ar command Ns Ic \&) substitutions, normal quoting rules are used when .Ar command is parsed; however, for the @@ -794,8 +834,8 @@ or .Ql \e is stripped (a .Ql \e -followed by any other character is unchanged). As a special case in command -substitutions, a command of the form +followed by any other character is unchanged). +As a special case in command substitutions, a command of the form .Ic \&< Ar file is interpreted to mean substitute the contents of .Ar file @@ -808,17 +848,20 @@ but it is carried out more efficiently because no process is started). .Sy Note: .Ic $( Ns Ar command Ns Ic \&) expressions are currently parsed by finding the matching parenthesis, -regardless of quoting. This should be fixed soon. +regardless of quoting. +This should be fixed soon. .Pp Arithmetic substitutions are replaced by the value of the specified expression. For example, the command .Ic echo $((2+3*4)) -prints 14. See +prints 14. +See .Sx Arithmetic expressions for a description of an expression. .Ss Parameters Parameters are shell variables; they can be assigned values and their values -can be accessed using a parameter substitution. A parameter name is either one +can be accessed using a parameter substitution. +A parameter name is either one of the special single punctuation or digit character parameters described below, or a letter followed by zero or more letters or digits .Po @@ -831,10 +874,9 @@ or .Ic ${ Ns Ar name Ns Ic \&} , where .Ar name -is a parameter name. If substitution is performed on a parameter that is not -set, a -.Dv NULL -string is substituted unless the +is a parameter name. +If substitution is performed on a parameter that is not set, a +null string is substituted unless the .Ic nounset option .Po @@ -844,12 +886,12 @@ or .Pc is set, in which case an error occurs. .Pp -Parameters can be assigned valued in a number of ways. First, the shell -implicitly sets some parameters like +Parameters can be assigned valued in a number of ways. +First, the shell implicitly sets some parameters like .Ic # , PWD , etc.; this is the only way the special single character parameters are set. -Second, parameters are imported from the shell's environment at startup. Third, -parameters can be assigned values on the command line, for example, +Second, parameters are imported from the shell's environment at startup. +Third, parameters can be assigned values on the command line, for example, .Ic FOO=bar sets the parameter .Ev FOO @@ -858,25 +900,27 @@ to multiple parameter assignments can be given on a single command line and they can be followed by a simple-command, in which case the assignments are in effect only for the duration of the command (such assignments are also -exported, see below for implications of this). Note that both the parameter -name and the +exported, see below for implications of this). +Note that both the parameter name and the .Ql = -must be unquoted for the shell to recognize a parameter assignment. The fourth -way of setting a parameter is with the +must be unquoted for the shell to recognize a parameter assignment. +The fourth way of setting a parameter is with the .Ic export , .Ic readonly and .Ic typeset commands; see their descriptions in the .Sx Command execution -section. Fifth, +section. +Fifth, .Ic for loops set parameters as well as the .Ic getopts , .Ic read and .Ic set Fl A -commands. Lastly, parameters can be assigned values using assignment operators +commands. +Lastly, parameters can be assigned values using assignment operators inside arithmetic expressions (see .Sx Arithmetic expressions below) or using the @@ -894,8 +938,10 @@ the environment (see .Xr environ 5 ) of commands run by the shell as .Ar name Ns No = Ns Ar value -pairs. The order in which parameters appear in the environment of a command is -unspecified. When the shell starts up, it extracts parameters and their values +pairs. +The order in which parameters appear in the environment of a command is +unspecified. +When the shell starts up, it extracts parameters and their values from its environment and automatically sets the export attribute for those parameters. .Pp @@ -946,7 +992,8 @@ it is substituted; otherwise, is printed on standard error (preceded by .Ar name Ns No \&: ) and an error occurs (normally causing termination of a shell script, function -or .-script). If word is omitted the string +or .-script). +If word is omitted the string .Dq parameter null or not set is used instead. .El @@ -989,7 +1036,8 @@ If .Ar pattern matches the beginning of the value of parameter .Ar name , -the matched text is deleted from the result of substitution. A single +the matched text is deleted from the result of substitution. +A single .Ql # results in the shortest match, and two of them result in the longest match. @@ -1008,8 +1056,8 @@ The following special parameters are implicitly set by the shell and cannot be set directly using assignments: .Bl -tag -width "1 ... 9" .It Ev \&! -Process ID of the last background process started. If no background processes -have been started, the parameter is not set. +Process ID of the last background process started. +If no background processes have been started, the parameter is not set. .It Ev \&# The number of positional parameters (i.e., $1, $2, etc.). .It Ev \&$ @@ -1022,8 +1070,8 @@ The concatenation of the current single letter options (see .Ic set command below for list of options). .It Ev \&? -The exit status of the last non-asynchronous command executed. If the last -command was killed by a signal, +The exit status of the last non-asynchronous command executed. +If the last command was killed by a signal, .Ic \&$\&? is set to 128 plus the signal number. .It Ev 0 @@ -1037,17 +1085,20 @@ option and the .Ar command-name was supplied, or the .Ar file -argument, if it was supplied. If the +argument, if it was supplied. +If the .Ic posix option is not set, .Ic \&$0 is the name of the current function or script. .It Ev 1 ... Ev 9 The first nine positional parameters that were supplied to the shell, function -or .-script. Further positional parameters may be accessed using +or .-script. +Further positional parameters may be accessed using .Ic ${ Ns Ar number Ns Ic \&} . .It Ev \&* -All positional parameters (except parameter 0), i.e., $1, $2, $3... If used +All positional parameters (except parameter 0), i.e., $1, $2, $3... +If used outside of double quotes, parameters are separate words (which are subjected to word splitting); if used within double quotes, parameters are separated by the first character of the @@ -1060,8 +1111,8 @@ is Same as .Ic \&$\&* , unless it is used inside double quotes, in which case a separate word is -generated for each positional parameter. If there are no positional parameters, -no word is generated. +generated for each positional parameter. +If there are no positional parameters, no word is generated. .Ic \&$\&@ can be used to access arguments, verbatim, without losing .Dv NULL @@ -1073,39 +1124,45 @@ The following parameters are set and/or used by the shell: .It Ev CDPATH Search path for the .Ic cd -built-in command. Works the same way as +built-in command. +Works the same way as .Ev PATH for those directories not beginning with .Ql / in .Ic cd -commands. Note that if +commands. +Note that if .Ev CDPATH is set and does not contain .Dq \&. -or contains an empty path, the current directory is not searched. Also, the +or contains an empty path, the current directory is not searched. +Also, the .Ic cd built-in command will display the resulting directory when a match is found in any search path other than the empty path. .It Ev COLUMNS -Set to the number of columns on the terminal or window. Currently set to the +Set to the number of columns on the terminal or window. +Currently set to the .Dq cols value as reported by .Xr stty 1 -if that value is non-zero. This parameter is used by +if that value is non-zero. +This parameter is used by .Ic set Fl o and .Ic kill -l commands to format information columns. .It Ev ENV If this parameter is found to be set after any profile files are executed, the -expanded value is used as a shell startup file. It typically contains function -and alias definitions. +expanded value is used as a shell startup file. +It typically contains function and alias definitions. .It Ev ERRNO Integer value of the shell's .Va errno -variable. It indicates the reason the last system call failed. Not yet -implemented. +variable. +It indicates the reason the last system call failed. +Not yet implemented. .It Ev EXECSHELL If set, this parameter is assumed to contain the shell that is to be used to execute commands that @@ -1121,7 +1178,8 @@ command (see below). Like .Ev PATH , but used when an undefined function is executed to locate the file defining the -function. It is also searched when a command can't be found using +function. +It is also searched when a command can't be found using .Ev PATH . See .Sx Functions @@ -1138,7 +1196,8 @@ below). Internal field separator, used during substitution and by the .Ic read command, to split values into distinct arguments; normally set to space, tab -and newline. See +and newline. +See .Sx Substitution above for details. .Pp @@ -1151,9 +1210,11 @@ The version of shell and the date the version was created (read-only). The line number of the function or shell script that is currently being executed. .It Ev LINES -Set to the number of lines on the terminal or window. Not yet implemented. +Set to the number of lines on the terminal or window. +Not yet implemented. .It Ev OLDPWD -The previous working directory. Unset if +The previous working directory. +Unset if .Ic cd has not successfully changed directories since the shell started, or if the shell doesn't know where it is. @@ -1169,14 +1230,16 @@ Assigning 1 to this parameter causes to process arguments from the beginning the next time it is invoked. .It Ev PATH A colon separated list of directories that are searched when looking for -commands and .'d files. An empty string resulting from a leading or trailing +commands and .'d files. +An empty string resulting from a leading or trailing colon, or two adjacent colons, is treated as a .Dq \&. , the current directory. .It Ev POSIXLY_CORRECT If set, this parameter causes the .Ic posix -option to be enabled. See +option to be enabled. +See .Sx POSIX mode below. .It Ev PPID @@ -1195,11 +1258,13 @@ used when more input is needed to complete a command. .It Ev PS4 Used to prefix commands that are printed during execution tracing (see .Ic set Fl x -command below). The prompt is printed verbatim (i.e., no substitutions are -done). Default is +command below). +The prompt is printed verbatim (i.e., no substitutions are done). +Default is .Dq \&+\ \& . .It Ev PWD -The current working directory. May be unset or +The current working directory. +May be unset or .Dv NULL if the shell doesn't know where it is. .It Ev REPLY @@ -1207,7 +1272,8 @@ Default parameter for the .Ic read command if no names are given. .It Ev TMPDIR -The directory shell temporary files are created in. If this parameter is not +The directory shell temporary files are created in. +If this parameter is not set, or does not contain the absolute path of a writable directory, temporary files are created in .Pa /tmp . @@ -1218,7 +1284,8 @@ on words starting with an unquoted .Ql ~ . The characters following the tilde, up to the first .Ql / , -if any, are assumed to be a login name. If the login name is empty, +if any, are assumed to be a login name. +If the login name is empty, .Ql + or .Ql - , @@ -1227,9 +1294,11 @@ the value of the .Ev PWD , or .Ev OLDPWD -parameter is substituted, respectively. Otherwise, the password file is +parameter is substituted, respectively. +Otherwise, the password file is searched for the login name, and the tilde expression is substituted with the -user's home directory. If the login name is not found in the password file or +user's home directory. +If the login name is not found in the password file or if any quoting or parameter substitution occurs in the login name, no substitution is performed. .Pp @@ -1256,30 +1325,34 @@ or .Ql * characters or .Dq [..] -sequences. Once brace expansion has been performed, the shell replaces file +sequences. +Once brace expansion has been performed, the shell replaces file name patterns with the sorted named of all the files that match the pattern -(if no files match, the word is left unchanged). The pattern elements have the -following meaning: +(if no files match, the word is left unchanged). +The pattern elements have the following meaning: .Bl -tag -width Ds .It Ic \&? Matches any single character. .It Ic \&* Matches any sequence of characters. .It Ic \&[ Ns No .. Ns Ic \&] -Matches any of the characters inside the brackets. Ranges of characters can be +Matches any of the characters inside the brackets. +Ranges of characters can be specified by separating two characters by a .Ql - (e.g., .Dq [a0-9] matches the letter .Dq a -or any digit). In order to represent itself, a +or any digit). +In order to represent itself, a .Ql - must either be quoted or the first or last character in the character list. Similarly, a .Ql \&] must be quoted or the first character in the list if it is to represent itself -instead of the end of the list. Also, a +instead of the end of the list. +Also, a .Ql ! appearing at the start of the list has special meaning (see below), so to represent itself it must be quoted or appear later in the list. @@ -1332,7 +1405,8 @@ expression) are not yet implemented. .Ss Input/output redirection When a command is executed, its standard input, standard output, and standard error (file descriptors 0, 1, and 2, respectively) are normally inherited from -the shell. Three exceptions to this are commands in pipelines, for which +the shell. +Three exceptions to this are commands in pipelines, for which standard input and/or standard output are those set up by the pipeline, asynchronous commands created when job control is disabled, for which standard input is initially set to be from @@ -1346,8 +1420,8 @@ If .Ar file does not exist, it is created; if it does exist, is a regular file and the .Ic noclobber -option is set, an error occurs; otherwise, the file is truncated. Note that this -means the command +option is set, an error occurs; otherwise, the file is truncated. +Note that this means the command .Ic cmd < foo > foo will open .Ar foo @@ -1366,7 +1440,8 @@ Same as .Ic \&> , except if .Ar file -exists it is appended to instead of being truncated. Also, the file is opened +exists it is appended to instead of being truncated. +Also, the file is opened in append mode, so writes always go to the end of the file (see .Fn open 2 ) . .It Ic \&< Ar file @@ -1383,8 +1458,10 @@ After reading the command line containing this kind of redirection (called a the shell copies lines from the command source into a temporary file until a line matching .Ar marker -is read. When the command is executed, standard input is redirected from the -temporary file. If +is read. +When the command is executed, standard input is redirected from the +temporary file. +If .Ar marker contains no quoted characters, the contents of the temporary file are processed as if enclosed in double quotes each time the command is executed, so @@ -1396,7 +1473,7 @@ escapes for .Ql ` , .Ql \e , and -.Dq \enewline . +.Ql \enewline . If multiple here documents are used on the same command line, they are saved in order. .It Ic \&<\&<\&- Ar marker @@ -1422,16 +1499,19 @@ except the operation is done on standard output. .Pp In any of the above redirections, the file descriptor that is redirected (i.e., standard input or standard output) can be explicitly given by preceding the -redirection with a single digit. Parameter, command, and arithmetic +redirection with a single digit. +Parameter, command, and arithmetic substitutions, tilde substitutions, and (if the shell is interactive) file name generation are all performed on the .Ar file , .Ar marker and .Ar fd -arguments of redirections. Note, however, that the results of any file name +arguments of redirections. +Note, however, that the results of any file name generation are only used if a single file is matched; if multiple files match, -the word with the expanded file name generation characters is used. Note +the word with the expanded file name generation characters is used. +Note that in restricted shells, redirections which can create files cannot be used. .Pp For simple-commands, redirections may appear anywhere in the command; for @@ -1440,7 +1520,8 @@ compound-commands .Ic if statements, etc. .Pc , -any redirections must appear at the end. Redirections are processed after +any redirections must appear at the end. +Redirections are processed after pipelines are created and in the order they are given, so .Pp .Ic cat /foo/bar 2\&>&1 \&> /dev/null \&| cat -n @@ -1535,7 +1616,8 @@ Arithmetic (bit-wise) .Tn NOT . .It Ic \&+\&+ Increment; must be applied to a parameter (not a literal or other expression). -The parameter is incremented by 1. When used as a prefix operator, the result +The parameter is incremented by 1. +When used as a prefix operator, the result is the incremented value of the parameter; when used as a postfix operator, the result is the original value of the parameter. .It Ic \&-\&- @@ -1544,8 +1626,8 @@ Similar to except the parameter is decremented by 1. .It Ic \&, Separates two arithmetic expressions; the left-hand side is evaluated first, -then the right. The result is the value of the expression on the right-hand -side. +then the right. +The result is the value of the expression on the right-hand side. .It Ic = Assignment; variable on the left is set to the value on the right. .It Xo Ic \&*= /= \&+= \&-= \&<\&<= @@ -1565,13 +1647,13 @@ is the same as .It Ic \&|\&| Logical .Tn OR ; -the result is 1 if either argument is non-zero, 0 if not. The right -argument is evaluated only if the left argument is zero. +the result is 1 if either argument is non-zero, 0 if not. +The right argument is evaluated only if the left argument is zero. .It Ic \&&\&& Logical .Tn AND ; -the result is 1 if both arguments are non-zero, 0 if not. The -right argument is evaluated only if the left argument is non-zero. +the result is 1 if both arguments are non-zero, 0 if not. +The right argument is evaluated only if the left argument is non-zero. .It Ic \&| Arithmetic (bit-wise) .Tn OR . @@ -1590,7 +1672,8 @@ Not equal; the result is 0 if both arguments are equal, 1 if not. Less than; the result is 1 if the left argument is less than the right, 0 if not. .It Ic \&<= \&>= \&> -Less than or equal, greater than or equal, greater than. See +Less than or equal, greater than or equal, greater than. +See .Ic \&< . .It Ic \&<\&< \&>\&> Shift left (right); the result is the left argument with its bits shifted left @@ -1599,8 +1682,8 @@ Shift left (right); the result is the left argument with its bits shifted left Addition, subtraction, multiplication, and division. .It Ic % Remainder; the result is the remainder of the division of the left argument by -the right. The sign of the result is unspecified if either argument is -negative. +the right. +The sign of the result is unspecified if either argument is negative. .It Xo Ao Ar arg1 Ac Ic \ \&? .Ao Ar arg2 Ac Ic \ \&: Ao Ar arg3 Ac .Xc @@ -1616,12 +1699,15 @@ Functions are defined using either Korn shell .Ic function Ar name syntax or the Bourne/POSIX shell .Fn name -syntax (see below for the difference between the two forms). Functions are like +syntax (see below for the difference between the two forms). +Functions are like .Li .-scripts -in that they are executed in the current environment. However, unlike +in that they are executed in the current environment. +However, unlike .Li .-scripts , shell arguments (i.e., positional parameters $1, $2, etc.) are never visible -inside them. When the shell is determining the location of a command, functions +inside them. +When the shell is determining the location of a command, functions are searched after special built-in commands, before regular and non-regular built-ins, and before the .Ev PATH @@ -1640,7 +1726,8 @@ may be used to create undefined functions; when an undefined function is executed, the shell searches the path specified in the .Ev FPATH parameter for a file with the same name as the function, which, if found, is -read and executed. If after executing the file the named function is found to +read and executed. +If after executing the file the named function is found to be defined, the function is executed; otherwise, the normal command search is continued (i.e., the shell searches the regular built-in command table and .Ev PATH ) . @@ -1658,24 +1745,28 @@ which can be set with .Ic typeset \&-ft and .Ic typeset \&-fx , -respectively. When a traced function is executed, the shell's +respectively. +When a traced function is executed, the shell's .Ic xtrace option is turned on for the function's duration; otherwise, the .Ic xtrace -option is turned off. The +option is turned off. +The .Dq export -attribute of functions is currently not used. In the original Korn shell, +attribute of functions is currently not used. +In the original Korn shell, exported functions are visible to shell scripts that are executed. .Pp Since functions are executed in the current shell environment, parameter assignments made inside functions are visible after the function completes. If this is not the desired effect, the .Ic typeset -command can be used inside a function to create a local parameter. Note that -special parameters (e.g., $$, $\&!) can't be scoped in this way. +command can be used inside a function to create a local parameter. +Note that special parameters (e.g., $$, $\&!) can't be scoped in this way. .Pp The exit status of a function is that of the last command executed in the -function. A function can be made to finish immediately using the +function. +A function can be made to finish immediately using the .Ic return command; this may also be used to explicitly specify the exit status. .Pp @@ -1703,12 +1794,13 @@ untouched, so using .Ic getopts inside a function interferes with using .Ic getopts -outside the function). In the future, the following differences will also be -added: +outside the function). +In the future, the following differences will also be added: .Bl -bullet -offset indent .It A separate trap/signal environment will be used during the execution of -functions. This will mean that traps set inside a function will not affect the +functions. +This will mean that traps set inside a function will not affect the shell's traps and signals that are not ignored in the shell (but may be trapped) will have their default effect in a function. .It @@ -1722,14 +1814,15 @@ The shell is intended to be compliant; however, in some cases, .Tn POSIX behaviour is contrary either to the original Korn shell behaviour or to user -convenience. How the shell behaves in these cases is determined by the state -of the +convenience. +How the shell behaves in these cases is determined by the state of the .Ic posix option .Pq Ic set Fl o Ic posix . If it is on, the .Tn POSIX -behaviour is followed; otherwise, it is not. The +behaviour is followed; otherwise, it is not. +The .Ic posix option is set automatically when the shell starts up if the environment contains the @@ -1755,15 +1848,16 @@ Occurrences of .Ic \e\&" inside double quoted .Ic `\&.\&.` -command substitutions. In +command substitutions. +In .Tn POSIX mode, the .Ic \e\&" is interpreted when the command is interpreted; in .Pf non- Tn POSIX mode, the -backslash is stripped before the command substitution is interpreted. For -example, +backslash is stripped before the command substitution is interpreted. +For example, .Ic echo \&"`echo \e\&"hi\e\&"`\&" produces .Dq \&"hi\&" @@ -1773,25 +1867,28 @@ mode, .Dq hi in .Pf non- Tn POSIX -mode. To avoid problems, use the +mode. +To avoid problems, use the .Ic $(...) form of command substitution. .It .Ic kill -l -output. In +output. +In .Tn POSIX mode, signal names are listed one per line; in .Pf non- Tn POSIX mode, -signal numbers, names and descriptions are printed in columns. In future, a new -option +signal numbers, names and descriptions are printed in columns. +In future, a new option .Po Fl v \ perhaps .Pc will be added to distinguish the two behaviours. .It .Ic fg -exit status. In +exit status. +In .Tn POSIX mode, the exit status is 0 if no errors occur; in .Pf non- Tn POSIX @@ -1809,18 +1906,20 @@ mode, options can start with either or .Ql + . .It -Brace expansion (also known as alternation). In +Brace expansion (also known as alternation). +In .Tn POSIX mode, brace expansion is disabled; in .Pf non- Tn POSIX -mode, brace expansion is enabled. Note that +mode, brace expansion is enabled. +Note that .Ic set Fl o Ic posix (or setting the .Ev POSIXLY_CORRECT parameter) automatically turns the .Ic braceexpand -option off, although it can be explicitly turned on later. +option off; however, it can be explicitly turned on later. .It .Ic set \&- . In @@ -1834,7 +1933,8 @@ options; in mode, it does. .It .Ic set -exit status. In +exit status. +In .Tn POSIX mode, the exit status of .Ic set @@ -1843,13 +1943,15 @@ is 0 if there are no errors; in mode, the exit status is that of any command substitutions performed in generating the .Ic set -command. For example, +command. +For example, .Ic set \&-\&- `false`; echo $? prints 0 in .Tn POSIX mode, 1 in .Pf non- Tn POSIX -mode. This construct is used in most shell scripts that use the old +mode. +This construct is used in most shell scripts that use the old .Xr getopt 1 command. .It @@ -1859,7 +1961,8 @@ Argument expansion of .Ic readonly , and .Ic typeset -commands. In +commands. +In .Tn POSIX mode, normal argument expansion is done; in .Pf non- Tn POSIX @@ -1867,7 +1970,8 @@ mode, field splitting, file globbing, brace expansion, and (normal) tilde expansion are turned off, while assignment tilde expansion is turned on. .It -Signal specification. In +Signal specification. +In .Tn POSIX mode, signals can be specified as digits, only if signal numbers match @@ -1877,13 +1981,15 @@ KILL=9, ALRM=14, and TERM=15); in .Pf non- Tn POSIX mode, signals can always be digits. .It -Alias expansion. In +Alias expansion. +In .Tn POSIX mode, alias expansion is only carried out when reading command words; in .Pf non- Tn POSIX mode, alias expansion is carried out on any -word following an alias that ended in a space. For example, the following +word following an alias that ended in a space. +For example, the following .Ic for loop .Pp @@ -1904,7 +2010,8 @@ in .Pf non- Tn POSIX mode. .It -Test. In +Test. +In .Tn POSIX mode, the expression .Ql Fl t @@ -1920,27 +2027,30 @@ test may be left out and defaults to 1). .El .Ss Command execution After evaluation of command-line arguments, redirections and parameter -assignments, the type of command is determined: a special built-in, a +assignments, the type of command is determined: a special built-in, a function, a regular built-in, or the name of a file to execute found using the .Ev PATH -parameter. The checks are made in the above order. Special built-in commands -differ from other commands in that the +parameter. +The checks are made in the above order. +Special built-in commands differ from other commands in that the .Ev PATH parameter is not used to find them, and an error during their execution can cause a non-interactive shell to exit and parameter assignments that are -specified before the command are kept after the command completes. Just to -confuse things, if the +specified before the command are kept after the command completes. +Just to confuse things, if the .Ic posix option is turned off (see .Ic set command below), some special commands are very special in that no field splitting, file globbing, brace expansion, nor tilde expansion is performed -on arguments that look like assignments. Regular built-in commands are -different only in that the +on arguments that look like assignments. +Regular built-in commands are different only in that the .Ev PATH parameter is not used to find them. .Pp -The original ksh and +The original +.Nm ksh +and .Tn POSIX differ somewhat in which commands are considered special or regular: @@ -1985,15 +2095,18 @@ The following described the special and regular built-in commands: .It Ic \&. Ar file Op Ar arg1 ... Execute the commands in .Ar file -in the current environment. The file is searched for in the directories of +in the current environment. +The file is searched for in the directories of .Ev PATH . If arguments are given, the positional parameters may be used to access them while .Ar file -is being executed. If no arguments are given, the positional parameters are +is being executed. +If no arguments are given, the positional parameters are those of the environment the command is used in. .It Ic \&: Op Ar ... -The null command. Exit status is set to zero. +The null command. +Exit status is set to zero. .It Xo Ic alias .Op Fl d | Ic +-t Op Fl r .Op Ic +-px @@ -2005,21 +2118,26 @@ The null command. Exit status is set to zero. .Xc Without arguments, .Ic alias -lists all aliases. For any name without a value, the existing alias is listed. +lists all aliases. +For any name without a value, the existing alias is listed. Any name with a value defines an alias (see .Sx Aliases above). .Pp -When listing aliases, one of two formats is used. Normally, aliases are listed -as +When listing aliases, one of two formats is used. +Normally, aliases are listed as .Ar name Ns No = Ar value , where .Ar value -is quoted. If options were preceded with +is quoted. +If options were preceded with .Ql + , -or a lone \&+ is given on the command line, only +or a lone +.Ql + +is given on the command line, only .Ar name -is printed. In addition, if the +is printed. +In addition, if the .Fl p option is used, each alias is prefixed with the string .Dq alias\ \& . @@ -2036,7 +2154,8 @@ with the export attribute (exporting an alias has no effect). The .Fl t option indicates that tracked aliases are to be listed/set (values specified on -the command line are ignored for tracked aliases). The +the command line are ignored for tracked aliases). +The .Fl r option indicates that all tracked aliases are to be reset. .Pp @@ -2047,11 +2166,11 @@ listed or set (see .Sx Tilde expansion above). .It Ic bg Op Ar job ... -Resume the specified stopped job(s) in the background. If no jobs are -specified, +Resume the specified stopped job(s) in the background. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic bind Op Fl m @@ -2088,7 +2207,8 @@ is set, it lists the search path for the directory containing .Ar dir . A .Dv NULL -path means the current directory. If +path means the current directory. +If .Ar dir is found in any component of the .Ev CDPATH @@ -2099,13 +2219,15 @@ If .Ar dir is missing, the home directory .Ev HOME -is used. If +is used. +If .Ar dir is .Ql - , the previous working directory is used (see .Ev OLDPWD -parameter). If the +parameter). +If the .Fl L option (logical path) is used or if the .Ic physical @@ -2115,13 +2237,15 @@ command below) isn't set, references to .Dq \&.\&. in .Ar dir -are relative to the path used to get to the directory. If the +are relative to the path used to get to the directory. +If the .Fl P option (physical path) is used or if the .Ic physical option is set, .Dq \&.\&. -is relative to the filesystem directory tree. The +is relative to the filesystem directory tree. +The .Ev PWD and .Ev OLDPWD @@ -2142,15 +2266,17 @@ directory. .Ar cmd is executed exactly as if .Ic command -had not been specified, with two exceptions. First, +had not been specified, with two exceptions. +First, .Ar cmd cannot be a shell function, and second, special built-in commands lose their specialness (i.e., redirection and utility errors do not cause the shell to -exit, and command assignments are not permanent). If the +exit, and command assignments are not permanent). +If the .Fl p option is given, a default search path is used instead of the current value of .Ev PATH -(the actual value of the default path is system dependent: on POSIXish +(the actual value of the default path is system dependent: on POSIXish systems, it is the value returned by .Ic getconf CS_PATH ) . .It Ic continue Op Ar level @@ -2168,7 +2294,8 @@ defaults to 1. .Op Ar arg ... .Xc Prints its arguments (separated by spaces) followed by a newline, to the -standard output. The newline is suppressed if any of the arguments contain the +standard output. +The newline is suppressed if any of the arguments contain the backslash sequence .Ql \ec . See the @@ -2177,7 +2304,8 @@ command below for a list of other backslash sequences that are recognized. .Pp The options are provided for compatibility with .Bx -shell scripts. The +shell scripts. +The .Fl n option suppresses the trailing newline, .Fl e @@ -2194,12 +2322,14 @@ The command is executed without forking, replacing the shell process. .Pp If no command is given except for I/O redirection, the I/O redirection is permanent and the shell is -not replaced. Any file descriptors which are opened or +not replaced. +Any file descriptors which are opened or .Xr dup 2 Ns No 'd in this way are made available to other executed commands (note that the Korn shell differs here: it does not pass on file descriptors greater than 2). .It Ic exit Op Ar status -The shell exits with the specified exit status. If +The shell exits with the specified exit status. +If .Ar status is not specified, the exit status is the current value of the .Ic \&? @@ -2207,9 +2337,9 @@ parameter. .It Xo Ic export Op Fl p .Op Ar parameter Ns Op \&= Ns Ar value .Xc -Sets the export attribute of the named parameters. Exported parameters are -passed in the environment to executed commands. If values are specified, the -named parameters are also assigned. +Sets the export attribute of the named parameters. +Exported parameters are passed in the environment to executed commands. +If values are specified, the named parameters are also assigned. .Pp If no parameters are specified, the names of all parameters with the export attribute are printed one per line, unless the @@ -2239,10 +2369,11 @@ are replaced with This command is usually accessed with the predefined .Ic alias r='fx -e -' . .It Ic fg Op Ar job ... -Resume the specified job(s) in the foreground. If no jobs are specified, +Resume the specified job(s) in the foreground. +If no jobs are specified, .Ic %\&+ -is assumed. This command is only available on systems which support job -control (see +is assumed. +This command is only available on systems which support job control (see .Sx Job control below for more information). .It Xo Ic getopts Ar optstring name @@ -2253,9 +2384,11 @@ parameters, if no arguments are given) and to check for legal options. .Ar optstring contains the option letters that .Ic getopts -is to recognize. If a letter is followed by a colon, the option is expected to -have an argument. Options that do not take arguments may be grouped in a single -argument. If an option takes an argument and the option character is not the +is to recognize. +If a letter is followed by a colon, the option is expected to +have an argument. +Options that do not take arguments may be grouped in a single argument. +If an option takes an argument and the option character is not the last character of the argument it is found in, the remainder of the argument is taken to be the option's argument; otherwise, the next argument is the option's argument. @@ -2281,14 +2414,15 @@ mark or a colon is placed in .Ar name (indicating an illegal option or missing argument, respectively) and .Ev OPTAG -is set to the option character that caused the problem. An error message is -also printed to standard error if +is set to the option character that caused the problem. +An error message is also printed to standard error if .Ar optstring does not being with a colon. .Pp When the end of the options is encountered, .Ic getopts -exits with a non-zero exit status. Options end at the first (non-option +exits with a non-zero exit status. +Options end at the first (non-option argument) argument that does not start with a .Ql - , or when a @@ -2309,9 +2443,11 @@ may lead to unexpected results. .It Xo Ic hash Op Fl r .Op Ar name ... .Xc -Without arguments, any hashed executable command pathnames are listed. The +Without arguments, any hashed executable command pathnames are listed. +The .Fl r -option causes all hashed commands to be removed from the hash table. Each +option causes all hashed commands to be removed from the hash table. +Each .Ar name is searched as if it were a command name and added to the hash table if it is an executable command. @@ -2319,14 +2455,18 @@ an executable command. .Op Ar job ... .Xc Display information about the specified job(s); if no jobs are specified, all -jobs are displayed. The +jobs are displayed. +The .Fl n option causes information to be displayed only for jobs that have changed -state since the last notification. If the +state since the last notification. +If the .Fl l -option is used, the process ID of each process in a job is also listed. The +option is used, the process ID of each process in a job is also listed. +The .Fl p -option causes only the process group of each job to be printed. See +option causes only the process group of each job to be printed. +See .Sx Job control below for the format of .Ar job @@ -2339,10 +2479,12 @@ and the displayed job. .Ar pgrp No } Ar ... .Xc Send the specified signal to the specified jobs, process IDs, or process -groups. If no signal is specified, the +groups. +If no signal is specified, the .Dv TERM -signal is sent. If a job is specified, the signal is sent to the job's -process group. See +signal is sent. +If a job is specified, the signal is sent to the job's process group. +See .Sx Job control below for the format of .Ar job . @@ -2359,9 +2501,11 @@ a short description of them are printed. .Xc .Ic print prints its arguments on the standard output, separated by spaces and -terminated with a newline. The +terminated with a newline. +The .Fl n -option suppresses the newline. By default, certain C escapes are translated. +option suppresses the newline. +By default, certain C escapes are translated. These include .Ql \eb , .Ql \ef , @@ -2382,7 +2526,8 @@ option. .Ql \e expansion may be inhibited with the .Fl r -option. The +option. +The .Fl s option prints to the history file instead of standard output, the .Fl u @@ -2407,11 +2552,13 @@ command, which does not process .Ql \e sequences unless the .Fl e -option is given. As above, the +option is given. +As above, the .Fl n option suppresses the trailing newline. .It Ic pwd Op Fl LP -Print the present working directory. If the +Print the present working directory. +If the .Fl L option is used or if the .Ic physical @@ -2419,7 +2566,8 @@ option (see .Ic set command below) isn't set, the logical path is printed (i.e., the path used to .Ic cd -to the current directory). If the +to the current directory). +If the .Fl P option (physical path) is used or if the .Ic physical @@ -2434,17 +2582,19 @@ using the .Ev IFS parameter (see .Sx Substitution -above), and assigns each field to the specified parameters. If there are more -parameters than fields, the extra parameters are set to +above), and assigns each field to the specified parameters. +If there are more parameters than fields, the extra parameters are set to .Dv NULL , or alternatively, if there are more fields than parameters, the last parameter -is assigned the remaining fields (inclusive of any separating spaces). If no -parameters are specified, the +is assigned the remaining fields (inclusive of any separating spaces). +If no parameters are specified, the .Ev REPLY -parameter is used. If the input line ends in a backslash and the +parameter is used. +If the input line ends in a backslash and the .Fl r option was not used, the backslash and the newline are stripped and more input -is read. If no input is read, +is read. +If no input is read, .Ic read exits with a non-zero status. .Pp @@ -2461,7 +2611,8 @@ options cause input to be read from file descriptor .Ar n or the current co-process (see .Sx Co-processes -above for comments on this), respectively. If the +above for comments on this), respectively. +If the .Fl s option is used, input is saved to the history file. .It Xo Ic readonly Op Fl p @@ -2469,8 +2620,10 @@ option is used, input is saved to the history file. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Sets the read-only attribute of the named parameters. If values are given, -parameters are set to them before setting the attribute. Once a parameter is +Sets the read-only attribute of the named parameters. +If values are given, +parameters are set to them before setting the attribute. +Once a parameter is made read-only, it cannot be unset and its value cannot be changed. .Pp If no parameters are specified, the names of all parameters with the read-only @@ -2487,8 +2640,8 @@ script, with exit status .Ar status . If no .Ar status -is given, the exit status of the last executed command is used. If used -outside of a function or +is given, the exit status of the last executed command is used. +If used outside of a function or .Ic \&. script, it has the same effect as .Ic exit . @@ -2540,7 +2693,8 @@ the rest are left untouched. All new parameters are created with the export attribute. .It Fl b Ic notify Print job notification messages asynchronously, instead of just before the -prompt. Only used if job control is enabled +prompt. +Only used if job control is enabled .Pq Fl m . .It Fl C Ic noclobber Prevent @@ -2554,7 +2708,8 @@ must be used to force an overwrite Exit (after executing the .Dv ERR trap) as soon as an error occurs or a command fails (i.e., exits with a -non-zero status). This does not apply to commands whose exit status is +non-zero status). +This does not apply to commands whose exit status is explicitly tested by a shell construct such as .Ic if , .Ic until , @@ -2568,34 +2723,39 @@ Do not expand file name patterns. .It Fl h Ic trackall Create tracked aliases for all executed commands (see .Sx Aliases -above). Enabled by default for non-interactive shells. +above). +Enabled by default for non-interactive shells. .It Fl i Ic interactive -Enable interactive mode. This can only be set/unset when the shell is invoked. +Enable interactive mode. +This can only be set/unset when the shell is invoked. .It Fl k Ic keyword Parameter assignments are recognized anywhere in a command. .It Fl l Ic login -The shell is a login shell. This can only be set/unset when the shell is -invoked (see +The shell is a login shell. +This can only be set/unset when the shell is invoked (see .Sx Shell startup above). .It Fl m Ic monitor Enable job control (default for interactive shells). .It Fl n lc noexec -Do not execute any commands. Useful for checking the syntax of scripts +Do not execute any commands. +Useful for checking the syntax of scripts (ignored if interactive). .It Fl p Ic privileged Set automatically if, when the shell starts, the read UID or GID does not match -the effective UID (EUID) or GID (EGID), respectively. See +the effective UID (EUID) or GID (EGID), respectively. +See .Sx Shell startup above for a description of what this means. .It Fl r Ic restricted -Enable restricted mode. This option can only be used when the shell is invoked. +Enable restricted mode. +This option can only be used when the shell is invoked. See .Sx Shell startup above for a description of what this means. .It Fl s Ic stdin -If used where the shell is invoked, commands are read from standard input. Set -automatically if the shell is invoked with no arguments. +If used where the shell is invoked, commands are read from standard input. +Set automatically if the shell is invoked with no arguments. .Pp When .Fl s @@ -2633,13 +2793,15 @@ must be used. .It Ic nohup Do not kill running jobs with a .Dv HUP -signal when a login shell exists. Currently set by default, but this will +signal when a login shell exists. +Currently set by default, but this will change in the future to be compatible with the original Korn shell (which doesn't have this option, but does send the .Dv HUP signal). .It Ic nolog -No effect. In the original Korn shell, this prevents function definitions from +No effect. +In the original Korn shell, this prevents function definitions from being stored in the history file. .It Ic physical Causes the @@ -2654,9 +2816,9 @@ directories instead of .Dq logical directories (i.e., the shell handles .Dq \&.\&. , -which allows the user to be oblivious of symbolic links to directories). Clear -by default. Note that setting this option does not affect the current value of -the +which allows the user to be oblivious of symbolic links to directories). +Clear by default. +Note that setting this option does not affect the current value of the .Ev PWD parameter; only the .Ic cd @@ -2670,13 +2832,15 @@ commands above for more details. .It Ic posix Enable .Tn POSIX -mode. See +mode. +See .Sx POSIX mode above. .It Ic vi Enable vi-like command-line editing (interactive shells only). .It Ic viraw -No effect. In the original Korn shell, unless +No effect. +In the original Korn shell, unless .Ic viraw was set, the vi command-line mode would let the tty driver do the work until .Tn ESC @@ -2696,7 +2860,8 @@ In vi command-line editing, do command and file name completion when tab (^I) is entered in insert mode. .El .Pp -These options can also be used upon invocation of the shell. The current set of +These options can also be used upon invocation of the shell. +The current set of options (with single letter names) can be found in the parameter .Dv \&- . .Ic set Fl o @@ -2705,11 +2870,12 @@ with no option name will list all the options and whether each is on or off; will print the long names of all options that are currently on. .Pp Remaining arguments, if any, are positional parameters and are assigned, in -order, to the positional parameters (i.e., $1, $2, etc.). If options end with +order, to the positional parameters (i.e., $1, $2, etc.). +If options end with .Ql -- -and there are no remaining arguments, all positional parameters are cleared. If -no options or arguments are given, the values of all names are printed. For -unknown historical reasons, a lone +and there are no remaining arguments, all positional parameters are cleared. +If no options or arguments are given, the values of all names are printed. +For unknown historical reasons, a lone .Ql - option is treated specially -- it clears both the .Fl x @@ -2732,15 +2898,18 @@ defaults to 1. evaluates the .Ar expression and returns zero status if true, 1 status if false, or greater than 1 if there -was an error. It is normally used as the condition command of +was an error. +It is normally used as the condition command of .Ic if and .Ic while -statements. The following basic expressions are available: +statements. +The following basic expressions are available: .Bl -tag -width 17n .It Ar str .Ar str -has non-zero length. Note that there is the potential for problems if +has non-zero length. +Note that there is the potential for problems if .Ar str turns out to be an operator (e.g., .Fl r ) . @@ -2816,8 +2985,8 @@ Shell .Ar option is set (see .Ic set -command above for a list of options). As a non-standard extension, if the -option starts with a +command above for a list of options). +As a non-standard extension, if the option starts with a .Ql ! , the test is negated; the test always fails if .Ar option @@ -2845,7 +3014,8 @@ is the same file as second .It Fl t Op Ar fd File descriptor .Ar fd -is a tty device. If the +is a tty device. +If the .Ic posix option is not set, .Ar fd @@ -2906,7 +3076,8 @@ is a file descriptor number), the .Ic test command will attempt to fake it for all tests that operate on files (except the .Fl e -test). For example, +test). +For example, .Ic \&[ -w /dev/fd/2 \&] tests if file descriptor 2 is writable. .Pp @@ -2969,7 +3140,8 @@ or .Dv ALRM ) or the number of the signal (see .Ic kill -l -command above). There are two special signals: +command above). +There are two special signals: .Dv EXIT (also known as 0), which is executed when the shell is about to exit, and .Dv ERR , @@ -2982,7 +3154,8 @@ option were see -- see .Ic set command above). .Dv EXIT -handlers are executed in the environment of the last executed command. Note +handlers are executed in the environment of the last executed command. +Note that for non-interactive shells, the trap handler cannot be changed for signals that were ignored when the shell started. .Pp @@ -3013,7 +3186,8 @@ A command that exits with a zero value. .Op Ns = Ns Ar value .Ar ... Oc .Xc -Display or set parameter attributes. With no +Display or set parameter attributes. +With no .Ar name arguments, parameter attributes are displayed; if no options are used, the current attributes of all parameters are printed as @@ -3031,7 +3205,8 @@ arguments are given, the attributes of the named parameters are set .Pq Ic \&- or cleared .Pq Ic \&+ . -Values for parameters may optionally be specified. If +Values for parameters may optionally be specified. +If .Ic typeset is used inside a function, any newly created parameters are local to the function. @@ -3040,7 +3215,8 @@ When .Fl f is used, .Ic typeset -operates on the attributes of functions. As with parameters, if no +operates on the attributes of functions. +As with parameters, if no .Ar name Ns s are given, functions are listed with their values (i.e., definitions) unless options are introduced with @@ -3050,22 +3226,27 @@ in which case only the function names are reported. .It Fl L Ns Ar n Left justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Leading whitespace (and zeros, if used with the +assigned value) is used. +Leading whitespace (and zeros, if used with the .Fl Z -option) is stripped. If necessary, values are either truncated or space padded +option) is stripped. +If necessary, values are either truncated or space padded to fit the field width. .It Fl R Ns Ar n Right justify attribute. .Ar n -specifies the field width. If +specifies the field width. +If .Ar n is not specified, the current width of a parameter (or the width of its first -assigned value) is used. Trailing whitespace is stripped. If necessary, values -are either stripped of leading characters or space padded to make them fit the -field width. +assigned value) is used. +Trailing whitespace is stripped. +If necessary, values are either stripped of leading characters or space +padded to make them fit the field width. .It Fl Z Ns Ar n Zero fill attribute. If not combined with .Fl L , @@ -3076,19 +3257,23 @@ except zero padding is used instead of space padding. Integer attribute. .Ar n specifies the base to use when displaying the integer (if not specified, the -base given in the first assignment is used). Parameters with this attribute may +base given in the first assignment is used). +Parameters with this attribute may be assigned values containing arithmetic expressions. .It Fl U -Unsigned integer attribute. Integers are printed as unsigned values (only +Unsigned integer attribute. +Integers are printed as unsigned values (only useful when combined with the .Fl i -option). This option is not in the original Korn shell. +option). +This option is not in the original Korn shell. .It Fl f -Function mode. Display or set functions and their attributes, instead of -parameters. +Function mode. +Display or set functions and their attributes, instead of parameters. .It Fl l -Lower case attribute. All upper case characters in values are converted to -lower case. (In the original Korn shell, this parameter meant +Lower case attribute. +All upper case characters in values are converted to lower case. +(In the original Korn shell, this parameter meant .Dq long integer when used with the .Fl i @@ -3097,52 +3282,63 @@ option.) Print complete .Ic typeset commands that can be used to re-create the attributes (but not the values) or -parameters. This is the default action (option exists for ksh93 compatibility). +parameters. +This is the default action (option exists for ksh93 compatibility). .It Fl r -Read-only attribute. Parameters with this attribute may not be assigned to or -unset. Once this attribute is set, it can not be turned off. +Read-only attribute. +Parameters with this attribute may not be assigned to or unset. +Once this attribute is set, it can not be turned off. .It Fl t -Tag attribute. Has no meaning to the shell; provided for application use. +Tag attribute. +Has no meaning to the shell; provided for application use. .Pp For functions, .Fl t -is the trace attribute. When functions with the trace attribute are executed, -the +is the trace attribute. +When functions with the trace attribute are executed, the .Ic xtrace .Pq Fl x shell option is temporarily turned on. .It Fl u -Upper case attribute. All lower case characters in values are converted to -upper case. (In the original Korn shell, this parameter meant +Upper case attribute. +All lower case characters in values are converted to upper case. +(In the original Korn shell, this parameter meant .Dq unsigned integer when used with the .Fl i option, which meant upper case letters would never be used for bases greater -than 10. See the +than 10. +See the .Fl U option.) .Pp For functions, .Fl u -is the undefined attribute. See +is the undefined attribute. +See .Sx Functions above for the implications of this. .It Fl x -Export attribute. Parameters (or functions) are placed in the environment of -any executed commands. Exported functions are not yet implemented. +Export attribute. +Parameters (or functions) are placed in the environment of +any executed commands. +Exported functions are not yet implemented. .El .It Xo Ic ulimit Op Fl acdfHlmnpsStvw .Op Ar value .Xc -Display or set process limits. If no options are used, the file size limit +Display or set process limits. +If no options are used, the file size limit .Pq Fl f is assumed. .Ar value , if specified, may be either an arithmetic expression or the word .Dq unlimited . The limits affect the shell and any processes created by the shell after a -limit is imposed. Note that some systems may not allow limits to be increased -once they are set. Also note that the types of limits available are system +limit is imposed. +Note that some systems may not allow limits to be increased +once they are set. +Also note that the types of limits available are system dependent -- some systems have only the .Fl f limit. @@ -3229,9 +3425,11 @@ and is equivalent (on most systems) to the octal mask .It Xo Ic unalias Op Fl adt .Op Ar name1 ... .Xc -The aliases for the given names are removed. If the +The aliases for the given names are removed. +If the .Fl a -option is used, all aliases are removed. If the +option is used, all aliases are removed. +If the .Fl t or .Fl d @@ -3250,7 +3448,8 @@ or functions The exit status is non-zero if any of the parameters were already unset, zero otherwise. .It Ic wait Op Ar job ... -Wait for the specified job(s) to finish. The exit status of +Wait for the specified job(s) to finish. +The exit status of .Ic wait is that of the last specified job; if the last job is killed by a signal, the exit status is 128 + the number of the signal (see @@ -3258,7 +3457,8 @@ exit status is 128 + the number of the signal (see above); if the last specified job can't be found (because it never existed, or had already finished), the exit status of .Ic wait -is 127. See +is 127. +See .Sx Job control below for the format of .Ar job . @@ -3273,7 +3473,8 @@ signal is received. If no jobs are specified, .Ic wait waits for all currently running jobs (if any) to finish and exits with a zero -status. If job monitoring is enabled, the completion status of jobs is printed +status. +If job monitoring is enabled, the completion status of jobs is printed (this is not the case when jobs are explicitly specified). .It Xo Ic whence Op Fl pv .Op Ar name ... @@ -3281,11 +3482,13 @@ status. If job monitoring is enabled, the completion status of jobs is printed For each .Ar name , the type of command is listed (reserved word, built-in, alias, -function, tracked alias, or executable). If the +function, tracked alias, or executable). +If the .Fl p option is used, a path search is performed even if .Ar name -is a reserved word, alias, etc. Without the +is a reserved word, alias, etc. +Without the .Fl v option, .Ic whence @@ -3293,7 +3496,8 @@ is similar to .Ic command Fl v except that .Ic whence -will find reserved words and won't print aliases as alias commands. With the +will find reserved words and won't print aliases as alias commands. +With the .Fl v option, .Ic whence @@ -3310,17 +3514,19 @@ status is non-zero. .El .Ss Job control Job control refers to the shell's ability to monitor and control jobs, which -are processes or groups of processes created for commands or pipelines. At a -minimum, the shell keeps track of the status of the background (i.e., +are processes or groups of processes created for commands or pipelines. +At a minimum, the shell keeps track of the status of the background (i.e., asynchronous) jobs that currently exist; this information can be displayed using the .Ic jobs -commands. If job control is fully enabled (using +commands. +If job control is fully enabled (using .Ic set Fl m or .Ic set Fl o Ic monitor ) , as it is for interactive shells, the processes of a job are placed in their -own process group. Foreground jobs can be stopped by typing the suspend +own process group. +Foreground jobs can be stopped by typing the suspend character from the terminal (normally ^Z), jobs can be restarted in either the foreground or background using the .Ic fg @@ -3335,11 +3541,12 @@ commands like .Ic read cannot be. .Pp -When a job is created, it is assigned a job number. For interactive shells, -this number is printed inside +When a job is created, it is assigned a job number. +For interactive shells, this number is printed inside .Dq \&[..\&] , followed by the process IDs of the processes in the job when an asynchronous -command is run. A job may be referred to in +command is run. +A job may be referred to in .Ic bg , .Ic fg , .Ic jobs , @@ -3412,12 +3619,14 @@ The job was stopped by the indicated .It Ar signal-description Op Dq core dumped The job was killed by a signal (e.g., memory fault, hangup, etc.; use .Ic kill -l -for a list of signal descriptions). The +for a list of signal descriptions). +The .Dq core dumped message indicates the process created a core file. .El .It Ar command -is the command that created the process. If there are multiple processes in +is the command that created the process. +If there are multiple processes in the job, each process will have a line showing its .Ar command and possibly its @@ -3430,10 +3639,12 @@ state, the shell warns the user that there are stopped jobs and does not exit. If another attempt is immediately made to exit the shell, the stopped jobs are sent a .Dv HUP -signal and the shell exits. Similarly, if the +signal and the shell exits. +Similarly, if the .Ic nohup option is not set and there are running jobs when an attempt is made to exit -a login shell, the shell warns the user and does not exit. If another attempt +a login shell, the shell warns the user and does not exit. +If another attempt is immediately made to exit the shell, the running jobs are sent a .Dv HUP signal and the shell exits. @@ -3490,7 +3701,8 @@ is implemented as a run-time option of with only those .Nm ksh features whose syntax or semantics are incompatible with a traditional Bourne -shell disabled. Since this leaves some +shell disabled. +Since this leaves some .Nm ksh extensions exposed, caution should be used where backwards compatibility with traditional Bourne or @@ -3499,7 +3711,8 @@ compliant shells is an issue. .Sh BUGS Any bugs in .Nm pdksh -should be reported to pdksh@cs.mun.ca. Please include the version of +should be reported to pdksh@cs.mun.ca. +Please include the version of .Nm pdksh .Po .Ic echo $KSH_VERSION @@ -3516,7 +3729,8 @@ and a copy of your .Pa config.h (the file generated by the .Pa configure -script). New version of +script). +New versions of .Nm pdksh can be obtained from ftp://ftp.cs.mun.ca/pub/pdksh. .Pp @@ -3529,11 +3743,13 @@ I'm aware of this and there is no need to report it. .Sh AUTHORS This shell is based on the public domain 7th edition Bourne shell clone by Charles Forsyth and parts of the BRL shell by Doug A. Gwyn, Doug Kingston, -Ron Natalie, Arnold Robbins, Lou Salkind, and others. The first release of +Ron Natalie, Arnold Robbins, Lou Salkind, and others. +The first release of .Nm pdksh was created by Eric Gisin, and it was subsequently maintained by John R. MacMillan (change!john@sq.sq.com) and Simon J. Gerraty (sjg@zen.void.oz.au). -The current maintainer is Michael Rendell (michael@cs.mun.ca). The +The current maintainer is Michael Rendell (michael@cs.mun.ca). +The .Pa CONTRIBUTORS file in the source distribution contains a more complete list of people and their part in the shell's development. diff --git a/bin/ls/ls.1 b/bin/ls/ls.1 index 42cd66805d0..b9f8d0970b5 100644 --- a/bin/ls/ls.1 +++ b/bin/ls/ls.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: ls.1,v 1.21 2000/01/05 18:48:31 aaron Exp $ +.\" $OpenBSD: ls.1,v 1.22 2000/03/17 18:15:14 aaron Exp $ .\" $NetBSD: ls.1,v 1.14 1995/12/05 02:44:01 jtc Exp $ .\" .\" Copyright (c) 1980, 1990, 1991, 1993, 1994 @@ -108,8 +108,8 @@ Recursively list subdirectories encountered. Sort by size, largest file first. .It Fl T Display complete time information for the file, including -month, day, hour, minute, second, and year. This option has no effect unless -one of the long format +month, day, hour, minute, second, and year. +This option has no effect unless one of the long format .Pq Fl l , Fl n options is also specified. .It Fl W @@ -137,8 +137,8 @@ For each file, print its inode number. .It Fl k Modifies the .Fl s -option, causing the sizes to be reported in kilobytes. Overrides any -value specified by the +option, causing the sizes to be reported in kilobytes. +Overrides any value specified by the .Ev BLOCKSIZE environment variable. .It Fl l @@ -171,8 +171,8 @@ Reverse the order of the sort to get reverse lexicographical order or the smallest or oldest entries first. .It Fl s Display the number of file system blocks actually used by each file, -where partial units are rounded up to the next integer value. Blocks -are 512 bytes unless overridden by the +where partial units are rounded up to the next integer value. +Blocks are 512 bytes unless overridden by the .Fl k flag or .Ev BLOCKSIZE @@ -212,7 +212,8 @@ The and .Fl u options override each other; the last one specified determines -the file time used. The +the file time used. +The .Fl f option overrides any occurrence of either. .Pp @@ -250,7 +251,8 @@ time of last modification and the pathname. In addition, for each directory whose contents are displayed, the first line displayed is the total number of blocks used by the files in the -directory. Blocks are 512 bytes unless overridden by the +directory. +Blocks are 512 bytes unless overridden by the .Fl k option or .Ev BLOCKSIZE @@ -280,8 +282,8 @@ The file mode printed under the or .Fl n options consists of the entry type, owner permissions, and group -permissions. The entry type character describes the type of file, as -follows: +permissions. +The entry type character describes the type of file, as follows: .Pp .Bl -tag -width 4n -offset indent -compact .It Sy b diff --git a/bin/md5/md5.1 b/bin/md5/md5.1 index b935c87e01e..304a6740d30 100644 --- a/bin/md5/md5.1 +++ b/bin/md5/md5.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: md5.1,v 1.7 1998/12/15 01:20:23 aaron Exp $ +.\" $OpenBSD: md5.1,v 1.8 2000/03/17 18:15:14 aaron Exp $ .\" .Dd February 14, 1994 .Dt MD5 1 @@ -27,7 +27,8 @@ such as .Em RSA . .Sh OPTIONS The following four options may be used in any combination and must -precede any files named on the command line. The MD5 +precede any files named on the command line. +The MD5 sum of each file listed on the command line is printed after the options are processed. .Bl -tag -width Fl diff --git a/bin/mkdir/mkdir.1 b/bin/mkdir/mkdir.1 index e5ac9b6798c..dcba2127f2b 100644 --- a/bin/mkdir/mkdir.1 +++ b/bin/mkdir/mkdir.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: mkdir.1,v 1.10 1999/09/23 19:52:48 aaron Exp $ +.\" $OpenBSD: mkdir.1,v 1.11 2000/03/17 18:15:14 aaron Exp $ .\" $NetBSD: mkdir.1,v 1.9 1995/07/25 19:37:13 jtc Exp $ .\" .\" Copyright (c) 1989, 1990, 1993 @@ -55,7 +55,7 @@ utility creates the directories named as operands, in the order specified, using mode .Li rwxrwxrwx (\&0777) as modified by the current -.Xr umask 2 . +.Xr umask 2 . .Pp The options are as follows: .Bl -tag -width indent @@ -79,7 +79,8 @@ operand must already exist. Intermediate directories are created with permission bits of .Li rwxrwxrwx (\&0777) as modified by the current umask, plus write and search -permission for the owner. Do not consider it an error if the +permission for the owner. +Do not consider it an error if the argument directory already exists. .El .Pp diff --git a/bin/mt/mt.1 b/bin/mt/mt.1 index b5e27ef4a95..f9d9e4b4dec 100644 --- a/bin/mt/mt.1 +++ b/bin/mt/mt.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: mt.1,v 1.14 1999/08/17 14:04:00 aaron Exp $ +.\" $OpenBSD: mt.1,v 1.15 2000/03/17 18:15:14 aaron Exp $ .\" $NetBSD: mt.1,v 1.8 1996/05/21 10:23:55 mrg Exp $ .\" .\" Copyright (c) 1981, 1990, 1993 @@ -55,8 +55,8 @@ The utility sends commands to a magnetic tape drive. By default, .Nm -performs the requested operation once. Operations -may be performed multiple times by specifying +performs the requested operation once. +Operations may be performed multiple times by specifying .Ar count . Note that @@ -72,8 +72,8 @@ or writes to the named tape device on the remote host using .Xr rmt 8 . .Pp -The available commands are listed below. Only as many -characters as are required to uniquely identify a command +The available commands are listed below. +Only as many characters as are required to uniquely identify a command need be specified. .Bl -tag -width "eof, weof" .It Cm eof , weof diff --git a/bin/mv/mv.1 b/bin/mv/mv.1 index 99df40ee642..a8e81a1eb3b 100644 --- a/bin/mv/mv.1 +++ b/bin/mv/mv.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: mv.1,v 1.8 1999/08/17 14:04:01 aaron Exp $ +.\" $OpenBSD: mv.1,v 1.9 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: mv.1,v 1.8 1995/03/21 09:06:51 cgd Exp $ .\" .\" Copyright (c) 1989, 1990, 1993 @@ -106,7 +106,7 @@ prompts the user for confirmation as specified for the option. .Pp As the -.Xr rename 2 +.Xr rename 2 call does not work across file systems, .Nm uses diff --git a/bin/pax/cpio.1 b/bin/pax/cpio.1 index 53ae6d27dc4..85c775ebec6 100644 --- a/bin/pax/cpio.1 +++ b/bin/pax/cpio.1 @@ -27,7 +27,7 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.\" $OpenBSD: cpio.1,v 1.9 2000/03/05 00:28:52 aaron Exp $ +.\" $OpenBSD: cpio.1,v 1.10 2000/03/17 18:15:15 aaron Exp $ .\" .Dd February 16, 1997 .Dt CPIO 1 @@ -70,7 +70,8 @@ archive. The options are as follows: .Bl -tag -width Fl .It Fl o -Create an archive. Reads the list of files to store in the +Create an archive. +Reads the list of files to store in the archive from standard input, and writes the archive on standard output. .Bl -tag -width Fl @@ -92,8 +93,8 @@ Set the block size of output to .It Fl O Ar archive Use the specified file name as the archive to write to. .It Fl H Ar format -Write the archive in the specified format. Recognized -formats are: +Write the archive in the specified format. +Recognized formats are: .Bl -tag -width Ds .It Ar bcpio Old binary cpio format. @@ -109,8 +110,8 @@ POSIX ustar format. .It Fl L Follow symbolic links. .It Fl v -Be verbose about operations. List filenames as they are -written to the archive. +Be verbose about operations. +List filenames as they are written to the archive. .It Fl z Compress archive using .Xr gzip 1 @@ -121,7 +122,8 @@ Compress archive using format. .El .It Fl i -Restore files from an archive. Reads the archive file from +Restore files from an archive. +Reads the archive file from standard input and extracts files matching the .Ar patterns that were specified on the command line. @@ -151,8 +153,8 @@ given on the command line. .It Fl I Ar archive Use the specified file as the input for the archive. .It Fl H Ar format -Read an archive of the specified format. Recognized -formats are: +Read an archive of the specified format. +Recognized formats are: .Bl -tag -width Ds .It Ar bcpio Old binary cpio format. @@ -180,8 +182,8 @@ directories will be created. Overwrite files even when the file in the archive is older than the one that will be overwritten. .It Fl v -Be verbose about operations. List filenames as they are -copied in from the archive. +Be verbose about operations. +List filenames as they are copied in from the archive. .It Fl z Uncompress archive using .Xr gzip 1 @@ -216,8 +218,8 @@ Restore modification times on files. Overwrite files even when the original file being copied is older than the one that will be overwritten. .It Fl v -Be verbose about operations. List filenames as they are -copied. +Be verbose about operations. +List filenames as they are copied. .El .El .Sh ERRORS @@ -238,7 +240,8 @@ ID, group ID, file mode or access and modification times when the .Fl p option is specified, a diagnostic message is written to standard error and a non-zero exit value will be returned, but processing -will continue. In the case where +will continue. +In the case where .Nm cannot create a link to a file, .Nm diff --git a/bin/pax/pax.1 b/bin/pax/pax.1 index f8feb04c1c2..d9b476479b4 100644 --- a/bin/pax/pax.1 +++ b/bin/pax/pax.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: pax.1,v 1.17 2000/03/14 21:31:41 aaron Exp $ +.\" $OpenBSD: pax.1,v 1.18 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: pax.1,v 1.3 1995/03/21 09:07:37 cgd Exp $ .\" .\" Copyright (c) 1992 Keith Muller. @@ -620,7 +620,8 @@ The optional trailing .Cm g continues to apply the substitution expression to the pathname substring which starts with the first character following the end of the last successful -substitution. The first unsuccessful substitution stops the operation of the +substitution. +The first unsuccessful substitution stops the operation of the .Cm g option. The optional trailing diff --git a/bin/pax/tar.1 b/bin/pax/tar.1 index d8235a95cd4..5de031f93dd 100644 --- a/bin/pax/tar.1 +++ b/bin/pax/tar.1 @@ -27,7 +27,7 @@ .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" -.\" $OpenBSD: tar.1,v 1.23 1999/08/16 18:40:03 aaron Exp $ +.\" $OpenBSD: tar.1,v 1.24 2000/03/17 18:15:15 aaron Exp $ .\" .Dd June 11, 1996 .Dt TAR 1 @@ -52,7 +52,8 @@ The .Nm command creates, adds files to, or extracts files from an -archive file in \*Qtar\*U format. A tar archive is often +archive file in \*Qtar\*U format. +A tar archive is often stored on a magnetic tape, but can be a floppy or a regular disk file. .Pp @@ -62,22 +63,27 @@ One of the following flags must be present: Create new archive, or overwrite an existing archive, adding the specified files to it. .It Fl r -Append the named new files to existing archive. Note that -this will only work on media on which an end-of-file mark +Append the named new files to existing archive. +Note that this will only work on media on which an end-of-file mark can be overwritten. .It Fl t -List contents of archive. If any files are named on the +List contents of archive. +If any files are named on the command line, only those files will be listed. .It Fl u Alias for .Fl r . .It Fl x -Extract files from archive. If any files are named on the +Extract files from archive. +If any files are named on the command line, only those files will be extracted from the -archive. If more than one copy of a file exists in the +archive. +If more than one copy of a file exists in the archive, later copies will overwrite earlier copies during -extraction. The file mode and modification time are preserved -if possible. The file mode is subject to modification by the +extraction. +The file mode and modification time are preserved +if possible. +The file mode is subject to modification by the .Xr umask 2 . .El .Pp @@ -87,14 +93,16 @@ flags may be used: .It Fl b Ar "blocking factor" Set blocking factor to use for the archive. .Nm -uses 512 byte blocks. The default is 20, the maximum is 126. +uses 512 byte blocks. +The default is 20, the maximum is 126. Archives with a blocking factor larger 63 violate the .Tn POSIX standard and will not be portable to all systems. .It Fl e Stop after first error. .It Fl f Ar archive -Filename where the archive is stored. Defaults to +Filename where the archive is stored. +Defaults to .Pa /dev/rst0 . .It Fl h Follow symbolic links as if they were normal files @@ -115,7 +123,8 @@ Preserve user and group ID as well as file mode regardless of the current .Xr umask 2 . The setuid and setgid bits are only preserved if the user is -the superuser. Only meaningful in conjunction with the +the superuser. +Only meaningful in conjunction with the .Fl x flag. .It Fl q @@ -160,7 +169,8 @@ The optional trailing .Cm g continues to apply the substitution expression to the pathname substring which starts with the first character following the end of the last successful -substitution. The first unsuccessful substitution stops the operation of the +substitution. +The first unsuccessful substitution stops the operation of the .Cm g option. The optional trailing @@ -174,7 +184,8 @@ are not selected and will be skipped. .It Fl v Verbose operation mode. .It Fl w -Interactively rename files. This option causes +Interactively rename files. +This option causes .Nm to prompt the user for the filename to use when storing or extracting files in an archive. @@ -182,7 +193,8 @@ extracting files in an archive. Compress archive using gzip. .It Fl C Ar directory This is a positional argument which sets the working directory for the -following files. When extracting, files will be extracted into +following files. +When extracting, files will be extracted into the specified directory; when creating, the specified files will be matched from the directory. .It Fl H @@ -235,7 +247,8 @@ ID, group ID, file mode or access and modification times when the .Fl p option is specified, a diagnostic message is written to standard error and a non-zero exit value will be returned, but processing -will continue. In the case where +will continue. +In the case where .Nm cannot create a link to a file, .Nm diff --git a/bin/ps/ps.1 b/bin/ps/ps.1 index 5a12ce50b42..62d132fb122 100644 --- a/bin/ps/ps.1 +++ b/bin/ps/ps.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: ps.1,v 1.23 1999/11/25 19:23:12 deraadt Exp $ +.\" $OpenBSD: ps.1,v 1.24 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: ps.1,v 1.16 1996/03/21 01:36:28 jtc Exp $ .\" .\" Copyright (c) 1980, 1990, 1991, 1993, 1994 @@ -336,7 +336,7 @@ controlling terminal (i.e., it has been revoked). .It wchan The event (an address in the system) on which a process waits. When printed numerically, the initial part of the address is -trimmed off and the result is printed in hex: for example, 0x80324000 prints +trimmed off and the result is printed in hex; for example, 0x80324000 prints as 324000. .El .Pp diff --git a/bin/rcp/rcp.1 b/bin/rcp/rcp.1 index eae74e56a11..75e54ae9c32 100644 --- a/bin/rcp/rcp.1 +++ b/bin/rcp/rcp.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: rcp.1,v 1.10 1999/08/17 14:04:01 aaron Exp $ +.\" $OpenBSD: rcp.1,v 1.11 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: rcp.1,v 1.6 1995/07/25 19:37:25 jtc Exp $ .\" .\" Copyright (c) 1983, 1990, 1993 @@ -53,7 +53,8 @@ .Sh DESCRIPTION The .Nm -utility copies files between machines. Each +utility copies files between machines. +Each .Ar file or .Ar directory @@ -92,7 +93,7 @@ By default, the mode and owner of .Ar file2 are preserved if it already existed; otherwise the mode of the source file modified by the -.Xr umask 2 +.Xr umask 2 on the destination host is used. .It Fl r If any of the source files are directories, @@ -126,7 +127,7 @@ so that the metacharacters are interpreted remotely. .Nm does not prompt for passwords; it performs remote execution via -.Xr rsh 1 , +.Xr rsh 1 , and requires the same authorization. .Pp .Nm diff --git a/bin/stty/stty.1 b/bin/stty/stty.1 index cfa7f29fa00..b7f957f7b09 100644 --- a/bin/stty/stty.1 +++ b/bin/stty/stty.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: stty.1,v 1.20 2000/03/06 21:46:56 aaron Exp $ +.\" $OpenBSD: stty.1,v 1.21 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: stty.1,v 1.10 1995/09/07 06:57:14 jtc Exp $ .\" .\" Copyright (c) 1990, 1993, 1994 @@ -78,8 +78,8 @@ formats. .It Fl f Ar file Open and use the terminal named by .Ar file -rather than using standard input. The file is opened -using the +rather than using standard input. +The file is opened using the .Dv O_NONBLOCK flag of .Xr open 2 , @@ -98,7 +98,8 @@ The following arguments are available to set the terminal characteristics: .Ss Control modes Control mode flags affect hardware characteristics associated with the -terminal. This corresponds to the +terminal. +This corresponds to the .Li c_cflag in the termios structure. .Bl -tag -width Fl @@ -226,12 +227,13 @@ to restart output. .It Cm imaxbel Pq Fl imaxbel The system imposes a limit of .Dv MAX_INPUT -(currently 255) characters in the input queue. If +(currently 255) characters in the input queue. +If .Cm imaxbel is set and the input queue limit has been reached, subsequent input causes the system to send an ASCII BEL -character to the output queue (the terminal beeps at you). Otherwise, -if +character to the output queue (the terminal beeps at you). +Otherwise, if .Cm imaxbel is unset and the input queue is full, the next input character causes the entire input and output queues to be discarded. @@ -352,7 +354,8 @@ Disable (enable) flush after .It Cm tostop Pq Fl tostop Send (do not send) .Dv SIGTTOU -for background output. This causes background jobs to stop if they attempt +for background output. +This causes background jobs to stop if they attempt terminal output. .It Cm altwerase Pq Fl altwerase Use (do not use) an alternate word erase algorithm when processing @@ -366,7 +369,8 @@ erased with simply an .Dv ERASE character). .It Cm mdmbuf Pq Fl mdmbuf -If set, flow control output based on condition of Carrier Detect. Otherwise +If set, flow control output based on condition of Carrier Detect. +Otherwise writes return an error if Carrier Detect is low (and Carrier is not being ignored with the .Dv CLOCAL @@ -454,7 +458,7 @@ Enable .Cm cs7 , and .Cm parodd . -.It Fl parity , evenp , oddp +.It Fl parity , evenp , oddp Disable .Cm parenb and set @@ -521,8 +525,8 @@ to a pty. .It Cm raw Pq Fl raw If set, change the modes of the terminal so that no input or output processing is performed. If unset, change the modes of the terminal to some reasonable -state that performs input and output processing. Note that since the -terminal driver no longer has a single +state that performs input and output processing. +Note that since the terminal driver no longer has a single .Dv RAW bit, it is not possible to intuit what flags were set prior to setting .Cm raw . @@ -651,7 +655,8 @@ The .Nm utility is expected to be .St -p1003.2 -compatible. The flags +compatible. +The flags .Fl e and .Fl f diff --git a/bin/test/test.1 b/bin/test/test.1 index b45bb69a011..c1aed009d26 100644 --- a/bin/test/test.1 +++ b/bin/test/test.1 @@ -1,4 +1,4 @@ -.\" $OpenBSD: test.1,v 1.10 1999/06/04 02:45:14 aaron Exp $ +.\" $OpenBSD: test.1,v 1.11 2000/03/17 18:15:15 aaron Exp $ .\" $NetBSD: test.1,v 1.6 1995/03/21 07:04:03 cgd Exp $ .\" .\" Copyright (c) 1991, 1993 @@ -103,7 +103,8 @@ True if .Ar file exists and is a symbolic link. This operator is for COMPATABILITY purposes, -do not rely on its existence. Use +do not rely on its existence. +Use .Fl L instead. .It Fl k Ar file @@ -299,12 +300,14 @@ operator. .Sh GRAMMAR AMBIGUITY The .Nm -grammar is inherently ambiguous. In order to assure a degree of consistency, +grammar is inherently ambiguous. +In order to assure a degree of consistency, the cases described in .St -p1003.2 section D11.2/4.62.4 are evaluated consistently according to the rules specified in the -standards document. All other cases are subject to the ambiguity in the +standards document. +All other cases are subject to the ambiguity in the command semantics. .Sh RETURN VALUES The