-.\" $OpenBSD: less.1,v 1.35 2014/05/01 18:53:22 jmc Exp $
+.\" $OpenBSD: less.1,v 1.36 2014/05/01 18:59:15 jmc Exp $
.\"
.\" Copyright (C) 1984-2012 Mark Nudelman
.\"
Commands may be preceded by a decimal number,
called N in the descriptions below.
The number is used by some commands, as indicated.
-.Sh COMMANDS
-In the following descriptions, ^X means control-X.
-ESC stands for the ESCAPE key; for example ESC-v means the
-two character sequence "ESCAPE", then "v".
-.Bl -tag -width XXXX
-.It Ic h | H
-Help: display a summary of these commands.
-If you forget all the other commands, remember this one.
-.It Ic SPACE | ^V | f | ^F
-Scroll forward N lines, default one window (see option -z below).
-If N is more than the screen size, only the final screenful is displayed.
-Warning: some systems use ^V as a special literalization character.
-.It Ic z
-Like SPACE, but if N is specified, it becomes the new window size.
-.It Ic ESC-SPACE
-Like SPACE, but scrolls a full screenful, even if it reaches
-end-of-file in the process.
-.It Ic ENTER | RETURN | ^N | e | ^E | j | ^J
-Scroll forward N lines, default 1.
-The entire N lines are displayed, even if N is more than the screen size.
-.It Ic d | ^D
-Scroll forward N lines, default one half of the screen size.
-If N is specified, it becomes the new default for subsequent d and u commands.
-.It Ic b | ^B | ESC-v
-Scroll backward N lines, default one window (see option -z below).
-If N is more than the screen size, only the final screenful is displayed.
-.It Ic w
-Like ESC-v, but if N is specified, it becomes the new window size.
-.It Ic y | ^Y | ^P | k | ^K
-Scroll backward N lines, default 1.
-The entire N lines are displayed, even if N is more than the screen size.
-Warning: some systems use ^Y as a special job control character.
-.It Ic u | ^U
-Scroll backward N lines, default one half of the screen size.
-If N is specified, it becomes the new default for subsequent d and u commands.
-.It Ic ESC-) | RIGHTARROW
-Scroll horizontally right N characters, default half the screen width
-(see the -# option).
-If a number N is specified, it becomes the default for future
-RIGHTARROW and LEFTARROW commands.
-While the text is scrolled, it acts as though the -S option (chop lines)
-were in effect.
-.It Ic ESC-( | LEFTARROW
-Scroll horizontally left N
-characters, default half the screen width (see the -# option).
-If a number N is specified, it becomes the default for future
-RIGHTARROW and LEFTARROW commands.
-.It Ic r | ^R | ^L
-Repaint the screen.
-.It Ic R
-Repaint the screen, discarding any buffered input.
-Useful if the file is changing while it is being viewed.
-.It Ic F
-Scroll forward, and keep trying to read when the end of file is reached.
-Normally this command would be used when already at the end of the file.
-It is a way to monitor the tail of a file which is growing
-while it is being viewed.
-(The behavior is similar to the "tail -f" command.)
-.It Ic ESC-F
-Like F, but as soon as a line is found which matches
-the last search pattern, the terminal bell is rung
-and forward scrolling stops.
-.It Ic g | < | ESC-<
-Go to line N in the file, default 1 (beginning of file).
-(Warning: this may be slow if N is large.)
-.It Ic G | > | ESC->
-Go to line N in the file, default the end of the file.
-(Warning: this may be slow if N is large,
-or if N is not specified and standard input, rather than a file,
-is being read.)
-.It Ic p | %
-Go to a position N percent into the file.
-N should be between 0 and 100, and may contain a decimal point.
-.It Ic P
-Go to the line containing byte offset N in the file.
-.It Ic {
-If a left curly bracket appears in the top line displayed
-on the screen, the { command will go to the matching right curly bracket.
-The matching right curly bracket is positioned on the bottom
-line of the screen.
-If there is more than one left curly bracket on the top line, a number N
-may be used to specify the N-th bracket on the line.
-.It Ic }
-If a right curly bracket appears in the bottom line displayed on the screen,
-the } command will go to the matching left curly bracket.
-The matching left curly bracket is positioned on the top
-line of the screen.
-If there is more than one right curly bracket on the top line,
-a number N may be used to specify the N-th bracket on the line.
-.It Ic \&(
-Like {, but applies to parentheses rather than curly brackets.
-.It Ic \&)
-Like }, but applies to parentheses rather than curly brackets.
-.It Ic \&[
-Like {, but applies to square brackets rather than curly brackets.
-.It Ic \&]
-Like }, but applies to square brackets rather than curly brackets.
-.It Ic ESC-^F
-Followed by two characters, acts like {,
-but uses the two characters as open and close brackets, respectively.
-For example, "ESC ^F < >" could be used to
-go forward to the > which matches the < in the top displayed line.
-.It Ic ESC-^B
-Followed by two characters, acts like },
-but uses the two characters as open and close brackets, respectively.
-For example, "ESC ^B < >" could be used to
-go backward to the < which matches the > in the bottom displayed line.
-.It Ic m
-Followed by any lowercase letter, marks the current position with that letter.
-.It Ic '
-(Single quote.)
-Followed by any lowercase letter, returns to the position which
-was previously marked with that letter.
-Followed by another single quote, returns to the position at
-which the last "large" movement command was executed.
-Followed by a ^ or $, jumps to the beginning or end of the file respectively.
-Marks are preserved when a new file is examined,
-so the ' command can be used to switch between input files.
-.It Ic ^X^X
-Same as single quote.
-.It Ic /pattern
-Search forward in the file for the N-th line containing the pattern.
-N defaults to 1.
-The pattern is a regular expression, as recognized by
-the regular expression library supplied by your system.
-The search starts at the first line displayed
-(but see the -a and -j options, which change this).
-.Pp
-Certain characters are special if entered at the beginning of the pattern;
-they modify the type of search rather than become part of the pattern:
-.Bl -tag -width Ds
-.It Ic ^N | \&!
-Search for lines which do NOT match the pattern.
-.It Ic ^E | *
-Search multiple files.
-That is, if the search reaches the END of the current file
-without finding a match,
-the search continues in the next file in the command line list.
-.It Ic ^F | @
-Begin the search at the first line of the FIRST file
-in the command line list,
-regardless of what is currently displayed on the screen
-or the settings of the -a or -j options.
-.It Ic ^K
-Highlight any text which matches the pattern on the current screen,
-but don't move to the first match (KEEP current position).
-.It Ic ^R
-Don't interpret regular expression metacharacters;
-that is, do a simple textual comparison.
-.El
-.It Ic ?pattern
-Search backward in the file for the N-th line containing the pattern.
-The search starts at the line immediately before the top line displayed.
-.Pp
-Certain characters are special, as in the / command:
-.Bl -tag -width Ds
-.It Ic ^N | \&!
-Search for lines which do NOT match the pattern.
-.It Ic ^E | *
-Search multiple files.
-That is, if the search reaches the beginning of the current file
-without finding a match,
-the search continues in the previous file in the command line list.
-.It Ic ^F | @
-Begin the search at the last line of the last file
-in the command line list,
-regardless of what is currently displayed on the screen
-or the settings of the -a or -j options.
-.It Ic ^K
-As in forward searches.
-.It Ic ^R
-As in forward searches.
-.El
-.It Ic ESC-/pattern
-Same as "/*".
-.It Ic ESC-?pattern
-Same as "?*".
-.It Ic n
-Repeat previous search, for N-th line containing the last pattern.
-If the previous search was modified by ^N, the search is made for the
-N-th line NOT containing the pattern.
-If the previous search was modified by ^E, the search continues
-in the next (or previous) file if not satisfied in the current file.
-If the previous search was modified by ^R, the search is done
-without using regular expressions.
-There is no effect if the previous search was modified by ^F or ^K.
-.It Ic N
-Repeat previous search, but in the reverse direction.
-.It Ic ESC-n
-Repeat previous search, but crossing file boundaries.
-The effect is as if the previous search were modified by *.
-.It Ic ESC-N
-Repeat previous search, but in the reverse direction
-and crossing file boundaries.
-.It Ic ESC-u
-Undo search highlighting.
-Turn off highlighting of strings matching the current search pattern.
-If highlighting is already off because of a previous ESC-u command,
-turn highlighting back on.
-Any search command will also turn highlighting back on.
-(Highlighting can also be disabled by toggling the -G option;
-in that case search commands do not turn highlighting back on.)
-.It Ic &pattern
-Display only lines which match the pattern;
-lines which do not match the pattern are not displayed.
-If pattern is empty (if you type & immediately followed by ENTER),
-any filtering is turned off, and all lines are displayed.
-While filtering is in effect, an ampersand is displayed at the
-beginning of the prompt,
-as a reminder that some lines in the file may be hidden.
-.Pp
-Certain characters are special as in the / command:
-.Bl -tag -width Ds
-.It Ic ^N | !
-Display only lines which do NOT match the pattern.
-.It Ic ^R
-Don't interpret regular expression metacharacters;
-that is, do a simple textual comparison.
-.El
-.It Ic :e Op Ar filename
-Examine a new file.
-If the filename is missing, the "current" file (see the :n and :p commands
-below) from the list of files in the command line is re-examined.
-A percent sign (%) in the filename is replaced by the name of the
-current file.
-A pound sign (#) is replaced by the name of the previously examined file.
-However, two consecutive percent signs are simply
-replaced with a single percent sign.
-This allows you to enter a filename that contains a percent sign
-in the name.
-Similarly, two consecutive pound signs are replaced with a single pound sign.
-The filename is inserted into the command line list of files
-so that it can be seen by subsequent :n and :p commands.
-If the filename consists of several files, they are all inserted into
-the list of files and the first one is examined.
-If the filename contains one or more spaces,
-the entire filename should be enclosed in double quotes
-(also see the -" option).
-.It Ic ^X^V | E
-Same as :e.
-Warning: some systems use ^V as a special literalization character.
-On such systems, you may not be able to use ^V.
-.It Ic :n
-Examine the next file (from the list of files given in the command line).
-If a number N is specified, the N-th next file is examined.
-.It Ic :p
-Examine the previous file in the command line list.
-If a number N is specified, the N-th previous file is examined.
-.It Ic :t
-Go to the specified tag.
-.It Ic :x
-Examine the first file in the command line list.
-If a number N is specified, the N-th file in the list is examined.
-.It Ic :d
-Remove the current file from the list of files.
-.It Ic t
-Go to the next tag, if there were more than one matches for the current tag.
-See the \-t option for more details about tags.
-.It Ic T
-Go to the previous tag, if there were more than one matches for the current tag.
-.It Ic = | ^G | :f
-Prints some information about the file being viewed, including its name
-and the line number and byte offset of the bottom line being displayed.
-If possible, it also prints the length of the file,
-the number of lines in the file
-and the percent of the file above the last displayed line.
-.It Ic \-
-Followed by one of the command line option letters (see
-.Sx OPTIONS
-below),
-this will change the setting of that option
-and print a message describing the new setting.
-If a ^P (CONTROL-P) is entered immediately after the dash,
-the setting of the option is changed but no message is printed.
-If the option letter has a numeric value (such as -b or -h),
-or a string value (such as -P or -t),
-a new value may be entered after the option letter.
-If no new value is entered, a message describing
-the current setting is printed and nothing is changed.
-.It Ic \-\-
-Like the \- command, but takes a long option name (see
-.Sx OPTIONS
-below)
-rather than a single option letter.
-You must press ENTER or RETURN after typing the option name.
-A ^P immediately after the second dash suppresses printing of a
-message describing the new setting, as in the \- command.
-.It Ic \-+
-Followed by one of the command line option letters this will reset the
-option to its default setting and print a message describing the new setting.
-(The "\-+X" command does the same thing as "\-+X" on the command line.)
-This does not work for string-valued options.
-.It Ic \-\-+
-Like the \-+ command, but takes a long option name
-rather than a single option letter.
-.It Ic \-!
-Followed by one of the command line option letters, this will reset the
-option to the "opposite" of its default setting and print a message
-describing the new setting.
-This does not work for numeric or string-valued options.
-.It Ic \-\-!
-Like the \-! command, but takes a long option name
-rather than a single option letter.
-.It Ic _
-(Underscore.)
-Followed by one of the command line option letters,
-this will print a message describing the current setting of that option.
-The setting of the option is not changed.
-.It Ic __
-(Double underscore.)
-Like the _ (underscore) command, but takes a long option name
-rather than a single option letter.
-You must press ENTER or RETURN after typing the option name.
-.It Ic +cmd
-Causes the specified cmd to be executed each time a new file is examined.
-For example, +G causes
-.Nm
-to initially display each file starting at the end rather than the beginning.
-.It Ic V
-Prints the version number of
-.Nm
-being run.
-.It Ic q | Q | :q | :Q | ZZ
-Exits
-.Nm less .
-.El
.Pp
-The following
-four
-commands may or may not be valid, depending on your particular installation.
-.Bl -tag -width XXXX
-.It Ic v
-Invokes an editor to edit the current file being viewed.
-The editor is taken from the environment variable
-.Ev VISUAL ,
-if defined,
-or
-.Ev EDITOR
-if
-.Ev VISUAL
-is not defined,
-or defaults to "vi" if neither
-.Ev VISUAL
-nor
-.Ev EDITOR
-is defined.
-See also the discussion of LESSEDIT under the section on
-.Sx PROMPTS
-below.
-.It Ic \&! Ar shell-command
-Invokes a shell to run the shell-command given.
-A percent sign (%) in the command is replaced by the name of the current file.
-A pound sign (#) is replaced by the name of the previously examined file.
-"!!" repeats the last shell command.
-"!" with no shell command simply invokes a shell.
-The shell is taken from the environment variable
-.Ev SHELL ,
-or defaults to "sh".
-.\" On MS-DOS and OS/2 systems, the shell is the normal command processor.
-.It Ic | <m> Ar shell-command
-<m> represents any mark letter.
-Pipes a section of the input file to the given shell command.
-The section of the file to be piped is between the first line on
-the current screen and the position marked by the letter.
-<m> may also be ^ or $ to indicate beginning or end of file respectively.
-If <m> is . or newline, the current screen is piped.
-.It Ic s Ar filename
-Save the input to a file.
-This only works if the input is a pipe, not an ordinary file.
-.El
-.Sh OPTIONS
Command line options are described below.
Most options may be changed while
.Nm
If the --use-backslash option is not in effect, then backslashes are
not treated specially, and there is no way to include a dollar sign
in the option string.
+.Pp
+The options are as follows:
.Bl -tag -width XXXX
.It Fl \&? | -help
This option displays a summary of the commands accepted by
.Nm
to prompt even more verbosely than
.Nm more .
-.It Fl m | -long-prompt
-Causes
+.It Fl m | -long-prompt
+Causes
+.Nm
+to prompt verbosely (like more), with the percent into the file.
+By default,
+.Nm
+prompts with a colon.
+.It Fl N | -LINE-NUMBERS
+Causes a line number to be displayed at the beginning of each line in the
+display.
+.It Fl n | -line-numbers
+Suppresses line numbers.
+The default (to use line numbers) may cause
+.Nm
+to run more slowly in some cases, especially with a very large input file.
+Suppressing line numbers with the -n option will avoid this problem.
+Using line numbers means: the line number will be displayed in the verbose
+prompt and in the = command, and the v command will pass the current line
+number to the editor (see also the discussion of LESSEDIT in
+.Sx PROMPTS
+below).
+.It Xo
+.Fl O Ar logfile |
+.Fl -LOG-FILE Ns = Ns Ar logfile
+.Xc
+The -O option is like -o, but it will overwrite an existing
+file without asking for confirmation.
+.Pp
+If no log file has been specified,
+the -o and -O options can be used from within
+.Nm
+to specify a log file.
+Without a file name, they will simply report the name of the log file.
+The "s" command is equivalent to specifying -o from within
+.Nm less .
+.It Xo
+.Fl o Ar logfile |
+.Fl -log-file Ns = Ns Ar logfile
+.Xc
+Causes
+.Nm
+to copy its input to the named file as it is being viewed.
+This applies only when the input file is a pipe, not an ordinary file.
+If the file already exists,
+.Nm
+will ask for confirmation before overwriting it.
+.It Xo
+.Fl P Ar prompt |
+.Fl -prompt Ns = Ns Ar prompt
+.Xc
+Provides a way to tailor the three prompt styles to your own preference.
+This option would normally be put in the
+.Ev LESS
+environment variable, rather than being typed in with each
+.Nm
+command.
+Such an option must either be the last option in the
+.Ev LESS
+variable, or be terminated by a dollar sign.
+-Ps followed by a string changes the default (short) prompt to that string.
+-Pm changes the medium (-m) prompt.
+-PM changes the long (-M) prompt.
+-Ph changes the prompt for the help screen.
+-P= changes the message printed by the = command.
+-Pw changes the message printed while waiting for data (in the F command).
+All prompt strings consist of a sequence of letters and special escape
+sequences.
+See the section on
+.Sx PROMPTS
+for more details.
+.It Xo
+.Fl p Ar pattern |
+.Fl -pattern Ns = Ns Ar pattern
+.Xc
+The -p option on the command line is equivalent to specifying +/pattern;
+that is, it tells
+.Nm
+to start at the first occurrence of pattern in the file.
+.It Fl Q | -QUIET | -SILENT
+Causes totally "quiet" operation: the terminal bell is never rung.
+.It Fl q | -quiet | -silent
+Causes moderately "quiet" operation:
+the terminal bell is not rung if an attempt is made to scroll past the end
+of the file or before the beginning of the file.
+If the terminal has a "visual bell", it is used instead.
+The bell will be rung on certain other errors,
+such as typing an invalid character.
+The default is to ring the terminal bell in all such cases.
+.It Fl R | -RAW-CONTROL-CHARS
+Like -r, but only ANSI "color" escape sequences are output in "raw" form.
+Unlike -r, the screen appearance is maintained correctly in most cases.
+ANSI "color" escape sequences are sequences of the form:
+.Pp
+.Dl ESC \&[ ... m
+.Pp
+where the "..." is zero or more color specification characters.
+For the purpose of keeping track of screen appearance,
+ANSI color escape sequences are assumed to not move the cursor.
+You can make
+.Nm
+think that characters other than "m" can end ANSI color escape sequences
+by setting the environment variable
+.Ev LESSANSIENDCHARS
+to the list of characters which can end a color escape sequence.
+And you can make
+.Nm
+think that characters other than the standard ones may appear between
+the ESC and the m by setting the environment variable
+.Ev LESSANSIMIDCHARS
+to the list of characters which can appear.
+.It Fl r | -raw-control-chars
+Causes "raw" control characters to be displayed.
+The default is to display control characters using the caret notation;
+for example, a control-A (octal 001) is displayed as "^A".
+Warning: when the -r option is used,
+.Nm
+cannot keep track of the actual appearance of the screen
+(since this depends on how the screen responds to
+each type of control character).
+Thus, various display problems may result,
+such as long lines being split in the wrong place.
+.It Fl S | -chop-long-lines
+Causes lines longer than the screen width to be
+chopped (truncated) rather than wrapped.
+That is, the portion of a long line that does not fit in
+the screen width is not shown.
+The default is to wrap long lines; that is, display the remainder
+on the next line.
+.It Fl s | -squeeze-blank-lines
+Causes consecutive blank lines to be squeezed into a single blank line.
+.It Xo
+.Fl T Ar tagsfile |
+.Fl -tag-file Ns = Ns Ar tagsfile
+.Xc
+Specifies a tags file to be used instead of "tags".
+.It Xo
+.Fl t Ar tag |
+.Fl -tag Ns = Ns Ar tag
+.Xc
+The -t option, followed immediately by a TAG,
+will edit the file containing that tag.
+For this to work, tag information must be available;
+for example, there may be a file in the current directory called "tags",
+which was previously built by
+.Xr ctags 1
+or an equivalent command.
+If the environment variable
+.Ev LESSGLOBALTAGS
+is set, it is taken to be the name of a command compatible with
+.Xr global ,
+and that command is executed to find the tag.
+(See
+.Lk http://www.gnu.org/software/global/global.html ) .
+The -t option may also be specified from within
+.Nm
+(using the \- command) as a way of examining a new file.
+The command ":t" is equivalent to specifying -t from within
+.Nm less .
+.It Fl U | -UNDERLINE-SPECIAL
+Causes backspaces, tabs and carriage returns to be
+treated as control characters;
+that is, they are handled as specified by the -r option.
+.Pp
+By default, if neither -u nor -U is given, backspaces which appear adjacent
+to an underscore character are treated specially:
+the underlined text is displayed
+using the terminal's hardware underlining capability.
+Also, backspaces which appear between two identical characters
+are treated specially:
+the overstruck text is printed
+using the terminal's hardware boldface capability.
+Other backspaces are deleted, along with the preceding character.
+Carriage returns immediately followed by a newline are deleted.
+Other carriage returns are handled as specified by the -r option.
+Text which is overstruck or underlined can be searched for
+if neither -u nor -U is in effect.
+.It Fl u | -underline-special
+Causes backspaces and carriage returns to be treated as printable characters;
+that is, they are sent to the terminal when they appear in the input.
+.It Fl V | -version
+Displays the version number of
+.Nm less .
+.It Fl W | -HILITE-UNREAD
+Like -w, but temporarily highlights the first new line after any
+forward movement command larger than one line.
+.It Fl w | -hilite-unread
+Temporarily highlights the first "new" line after a forward movement
+of a full page.
+The first "new" line is the line immediately following the line previously
+at the bottom of the screen.
+Also highlights the target line after a g or p command.
+The highlight is removed at the next command which causes movement.
+The entire line is highlighted, unless the -J option is in effect,
+in which case only the status column is highlighted.
+.It Fl X | -no-init
+Disables sending the termcap initialization and deinitialization strings
+to the terminal.
+This is sometimes desirable if the deinitialization string does
+something unnecessary, like clearing the screen.
+.It Xo
+.Fl x Ar n Ns , Ns Ar ... |
+.Fl -tabs Ns = Ns Ar n Ns , Ns Ar ...
+.Xc
+Sets tab stops.
+If only one n is specified, tab stops are set at multiples of n.
+If multiple values separated by commas are specified, tab stops are set at
+those positions, and then continue with the same spacing as the last two.
+For example, -x9,17 will set tabs at positions 9, 17, 25, 33, etc.
+The default for n is 8.
+.It Xo
+.Fl y Ar n |
+.Fl -max-forw-scroll Ns = Ns Ar n
+.Xc
+Specifies a maximum number of lines to scroll forward.
+If it is necessary to scroll forward more than n lines,
+the screen is repainted instead.
+The -c or -C option may be used to repaint from the top of
+the screen if desired.
+By default, any forward movement causes scrolling.
+.It Xo
+.Fl z Ar n |
+.Fl -window Ns = Ns Ar n
+.Xc
+Changes the default scrolling window size to n lines.
+The default is one screenful.
+The z and w commands can also be used to change the window size.
+The "z" may be omitted for compatibility with some versions of
+.Nm more .
+If the number
+.Ar n
+is negative, it indicates
+.Ar n
+lines less than the current screen size.
+For example, if the screen is 24 lines, -z-4 sets the
+scrolling window to 20 lines.
+If the screen is resized to 40 lines,
+the scrolling window automatically changes to 36 lines.
+.It Fl -follow-name
+Normally, if the input file is renamed while an F command is executing,
.Nm
-to prompt verbosely (like more), with the percent into the file.
-By default,
+will continue to display the contents of the original file despite
+its name change.
+If --follow-name is specified, during an F command
.Nm
-prompts with a colon.
-.It Fl N | -LINE-NUMBERS
-Causes a line number to be displayed at the beginning of each line in the
-display.
-.It Fl n | -line-numbers
-Suppresses line numbers.
-The default (to use line numbers) may cause
+will periodically attempt to reopen the file by name.
+If the reopen succeeds and the file is a different file from the original
+(which means that a new file has been created
+with the same name as the original (now renamed) file),
.Nm
-to run more slowly in some cases, especially with a very large input file.
-Suppressing line numbers with the -n option will avoid this problem.
-Using line numbers means: the line number will be displayed in the verbose
-prompt and in the = command, and the v command will pass the current line
-number to the editor (see also the discussion of LESSEDIT in
-.Sx PROMPTS
-below).
+will display the contents of that new file.
+.It Fl -no-keypad
+Disables sending the keypad initialization and deinitialization strings
+to the terminal.
+This is sometimes useful if the keypad strings make the numeric
+keypad behave in an undesirable manner.
+.It Fl -use-backslash
+This option changes the interpretations of options which follow this one.
+After the --use-backslash option, any backslash in an option string is
+removed and the following character is taken literally.
+This allows a dollar sign to be included in option strings.
.It Xo
-.Fl O Ar logfile |
-.Fl -LOG-FILE Ns = Ns Ar logfile
+.Ar -cc |
+.Fl -quotes Ns = Ns Ar cc
.Xc
-The -O option is like -o, but it will overwrite an existing
-file without asking for confirmation.
+Changes the filename quoting character.
+This may be necessary if you are trying to name a file
+which contains both spaces and quote characters.
+Followed by a single character, this changes the quote character to that
+character.
+Filenames containing a space should then be surrounded by that character
+rather than by double quotes.
+Followed by two characters, changes the open quote to the first character,
+and the close quote to the second character.
+Filenames containing a space should then be preceded by the open quote
+character and followed by the close quote character.
+Note that even after the quote characters are changed, this option
+remains -" (a dash followed by a double quote).
+.It Fl ~ | -tilde
+Normally lines after end of file are displayed as a single tilde (~).
+This option causes lines after end of file to be displayed as blank lines.
+.It Fl # | -shift
+Specifies the default number of positions to scroll horizontally
+in the RIGHTARROW and LEFTARROW commands.
+If the number specified is zero, it sets the default number of
+positions to one half of the screen width.
+Alternately, the number may be specified as a fraction of the width
+of the screen, starting with a decimal point: .5 is half of the
+screen width, .3 is three tenths of the screen width, and so on.
+If the number is specified as a fraction, the actual number of
+scroll positions is recalculated if the terminal window is resized,
+so that the actual scroll remains at the specified fraction
+of the screen width.
+.It Fl -
+A command line argument of "--" marks the end of option arguments.
+Any arguments following this are interpreted as filenames.
+This can be useful when viewing a file whose name begins with a "-" or "+".
+.It Cm +
+If a command line option begins with +,
+the remainder of that option is taken to be an initial command to
+.Nm less .
+For example, +G tells
+.Nm
+to start at the end of the file rather than the beginning,
+and +/xyz tells it to start at the first occurrence of "xyz" in the file.
+As a special case, +<number> acts like +<number>g;
+that is, it starts the display at the specified line number
+(however, see the caveat under the "g" command above).
+If the option starts with ++, the initial command applies to
+every file being viewed, not just the first one.
+The + command described previously
+may also be used to set (or change) an initial command for every file.
+.El
+.Sh COMMANDS
+In the following descriptions, ^X means control-X.
+ESC stands for the ESCAPE key; for example ESC-v means the
+two character sequence "ESCAPE", then "v".
+.Bl -tag -width XXXX
+.It Ic h | H
+Help: display a summary of these commands.
+If you forget all the other commands, remember this one.
+.It Ic SPACE | ^V | f | ^F
+Scroll forward N lines, default one window (see option -z below).
+If N is more than the screen size, only the final screenful is displayed.
+Warning: some systems use ^V as a special literalization character.
+.It Ic z
+Like SPACE, but if N is specified, it becomes the new window size.
+.It Ic ESC-SPACE
+Like SPACE, but scrolls a full screenful, even if it reaches
+end-of-file in the process.
+.It Ic ENTER | RETURN | ^N | e | ^E | j | ^J
+Scroll forward N lines, default 1.
+The entire N lines are displayed, even if N is more than the screen size.
+.It Ic d | ^D
+Scroll forward N lines, default one half of the screen size.
+If N is specified, it becomes the new default for subsequent d and u commands.
+.It Ic b | ^B | ESC-v
+Scroll backward N lines, default one window (see option -z below).
+If N is more than the screen size, only the final screenful is displayed.
+.It Ic w
+Like ESC-v, but if N is specified, it becomes the new window size.
+.It Ic y | ^Y | ^P | k | ^K
+Scroll backward N lines, default 1.
+The entire N lines are displayed, even if N is more than the screen size.
+Warning: some systems use ^Y as a special job control character.
+.It Ic u | ^U
+Scroll backward N lines, default one half of the screen size.
+If N is specified, it becomes the new default for subsequent d and u commands.
+.It Ic ESC-) | RIGHTARROW
+Scroll horizontally right N characters, default half the screen width
+(see the -# option).
+If a number N is specified, it becomes the default for future
+RIGHTARROW and LEFTARROW commands.
+While the text is scrolled, it acts as though the -S option (chop lines)
+were in effect.
+.It Ic ESC-( | LEFTARROW
+Scroll horizontally left N
+characters, default half the screen width (see the -# option).
+If a number N is specified, it becomes the default for future
+RIGHTARROW and LEFTARROW commands.
+.It Ic r | ^R | ^L
+Repaint the screen.
+.It Ic R
+Repaint the screen, discarding any buffered input.
+Useful if the file is changing while it is being viewed.
+.It Ic F
+Scroll forward, and keep trying to read when the end of file is reached.
+Normally this command would be used when already at the end of the file.
+It is a way to monitor the tail of a file which is growing
+while it is being viewed.
+(The behavior is similar to the "tail -f" command.)
+.It Ic ESC-F
+Like F, but as soon as a line is found which matches
+the last search pattern, the terminal bell is rung
+and forward scrolling stops.
+.It Ic g | < | ESC-<
+Go to line N in the file, default 1 (beginning of file).
+(Warning: this may be slow if N is large.)
+.It Ic G | > | ESC->
+Go to line N in the file, default the end of the file.
+(Warning: this may be slow if N is large,
+or if N is not specified and standard input, rather than a file,
+is being read.)
+.It Ic p | %
+Go to a position N percent into the file.
+N should be between 0 and 100, and may contain a decimal point.
+.It Ic P
+Go to the line containing byte offset N in the file.
+.It Ic {
+If a left curly bracket appears in the top line displayed
+on the screen, the { command will go to the matching right curly bracket.
+The matching right curly bracket is positioned on the bottom
+line of the screen.
+If there is more than one left curly bracket on the top line, a number N
+may be used to specify the N-th bracket on the line.
+.It Ic }
+If a right curly bracket appears in the bottom line displayed on the screen,
+the } command will go to the matching left curly bracket.
+The matching left curly bracket is positioned on the top
+line of the screen.
+If there is more than one right curly bracket on the top line,
+a number N may be used to specify the N-th bracket on the line.
+.It Ic \&(
+Like {, but applies to parentheses rather than curly brackets.
+.It Ic \&)
+Like }, but applies to parentheses rather than curly brackets.
+.It Ic \&[
+Like {, but applies to square brackets rather than curly brackets.
+.It Ic \&]
+Like }, but applies to square brackets rather than curly brackets.
+.It Ic ESC-^F
+Followed by two characters, acts like {,
+but uses the two characters as open and close brackets, respectively.
+For example, "ESC ^F < >" could be used to
+go forward to the > which matches the < in the top displayed line.
+.It Ic ESC-^B
+Followed by two characters, acts like },
+but uses the two characters as open and close brackets, respectively.
+For example, "ESC ^B < >" could be used to
+go backward to the < which matches the > in the bottom displayed line.
+.It Ic m
+Followed by any lowercase letter, marks the current position with that letter.
+.It Ic '
+(Single quote.)
+Followed by any lowercase letter, returns to the position which
+was previously marked with that letter.
+Followed by another single quote, returns to the position at
+which the last "large" movement command was executed.
+Followed by a ^ or $, jumps to the beginning or end of the file respectively.
+Marks are preserved when a new file is examined,
+so the ' command can be used to switch between input files.
+.It Ic ^X^X
+Same as single quote.
+.It Ic /pattern
+Search forward in the file for the N-th line containing the pattern.
+N defaults to 1.
+The pattern is a regular expression, as recognized by
+the regular expression library supplied by your system.
+The search starts at the first line displayed
+(but see the -a and -j options, which change this).
.Pp
-If no log file has been specified,
-the -o and -O options can be used from within
-.Nm
-to specify a log file.
-Without a file name, they will simply report the name of the log file.
-The "s" command is equivalent to specifying -o from within
-.Nm less .
-.It Xo
-.Fl o Ar logfile |
-.Fl -log-file Ns = Ns Ar logfile
-.Xc
-Causes
-.Nm
-to copy its input to the named file as it is being viewed.
-This applies only when the input file is a pipe, not an ordinary file.
-If the file already exists,
-.Nm
-will ask for confirmation before overwriting it.
-.It Xo
-.Fl P Ar prompt |
-.Fl -prompt Ns = Ns Ar prompt
-.Xc
-Provides a way to tailor the three prompt styles to your own preference.
-This option would normally be put in the
-.Ev LESS
-environment variable, rather than being typed in with each
-.Nm
-command.
-Such an option must either be the last option in the
-.Ev LESS
-variable, or be terminated by a dollar sign.
--Ps followed by a string changes the default (short) prompt to that string.
--Pm changes the medium (-m) prompt.
--PM changes the long (-M) prompt.
--Ph changes the prompt for the help screen.
--P= changes the message printed by the = command.
--Pw changes the message printed while waiting for data (in the F command).
-All prompt strings consist of a sequence of letters and special escape
-sequences.
-See the section on
-.Sx PROMPTS
-for more details.
-.It Xo
-.Fl p Ar pattern |
-.Fl -pattern Ns = Ns Ar pattern
-.Xc
-The -p option on the command line is equivalent to specifying +/pattern;
-that is, it tells
-.Nm
-to start at the first occurrence of pattern in the file.
-.It Fl Q | -QUIET | -SILENT
-Causes totally "quiet" operation: the terminal bell is never rung.
-.It Fl q | -quiet | -silent
-Causes moderately "quiet" operation:
-the terminal bell is not rung if an attempt is made to scroll past the end
-of the file or before the beginning of the file.
-If the terminal has a "visual bell", it is used instead.
-The bell will be rung on certain other errors,
-such as typing an invalid character.
-The default is to ring the terminal bell in all such cases.
-.It Fl R | -RAW-CONTROL-CHARS
-Like -r, but only ANSI "color" escape sequences are output in "raw" form.
-Unlike -r, the screen appearance is maintained correctly in most cases.
-ANSI "color" escape sequences are sequences of the form:
+Certain characters are special if entered at the beginning of the pattern;
+they modify the type of search rather than become part of the pattern:
+.Bl -tag -width Ds
+.It Ic ^N | \&!
+Search for lines which do NOT match the pattern.
+.It Ic ^E | *
+Search multiple files.
+That is, if the search reaches the END of the current file
+without finding a match,
+the search continues in the next file in the command line list.
+.It Ic ^F | @
+Begin the search at the first line of the FIRST file
+in the command line list,
+regardless of what is currently displayed on the screen
+or the settings of the -a or -j options.
+.It Ic ^K
+Highlight any text which matches the pattern on the current screen,
+but don't move to the first match (KEEP current position).
+.It Ic ^R
+Don't interpret regular expression metacharacters;
+that is, do a simple textual comparison.
+.El
+.It Ic ?pattern
+Search backward in the file for the N-th line containing the pattern.
+The search starts at the line immediately before the top line displayed.
.Pp
-.Dl ESC \&[ ... m
+Certain characters are special, as in the / command:
+.Bl -tag -width Ds
+.It Ic ^N | \&!
+Search for lines which do NOT match the pattern.
+.It Ic ^E | *
+Search multiple files.
+That is, if the search reaches the beginning of the current file
+without finding a match,
+the search continues in the previous file in the command line list.
+.It Ic ^F | @
+Begin the search at the last line of the last file
+in the command line list,
+regardless of what is currently displayed on the screen
+or the settings of the -a or -j options.
+.It Ic ^K
+As in forward searches.
+.It Ic ^R
+As in forward searches.
+.El
+.It Ic ESC-/pattern
+Same as "/*".
+.It Ic ESC-?pattern
+Same as "?*".
+.It Ic n
+Repeat previous search, for N-th line containing the last pattern.
+If the previous search was modified by ^N, the search is made for the
+N-th line NOT containing the pattern.
+If the previous search was modified by ^E, the search continues
+in the next (or previous) file if not satisfied in the current file.
+If the previous search was modified by ^R, the search is done
+without using regular expressions.
+There is no effect if the previous search was modified by ^F or ^K.
+.It Ic N
+Repeat previous search, but in the reverse direction.
+.It Ic ESC-n
+Repeat previous search, but crossing file boundaries.
+The effect is as if the previous search were modified by *.
+.It Ic ESC-N
+Repeat previous search, but in the reverse direction
+and crossing file boundaries.
+.It Ic ESC-u
+Undo search highlighting.
+Turn off highlighting of strings matching the current search pattern.
+If highlighting is already off because of a previous ESC-u command,
+turn highlighting back on.
+Any search command will also turn highlighting back on.
+(Highlighting can also be disabled by toggling the -G option;
+in that case search commands do not turn highlighting back on.)
+.It Ic &pattern
+Display only lines which match the pattern;
+lines which do not match the pattern are not displayed.
+If pattern is empty (if you type & immediately followed by ENTER),
+any filtering is turned off, and all lines are displayed.
+While filtering is in effect, an ampersand is displayed at the
+beginning of the prompt,
+as a reminder that some lines in the file may be hidden.
.Pp
-where the "..." is zero or more color specification characters.
-For the purpose of keeping track of screen appearance,
-ANSI color escape sequences are assumed to not move the cursor.
-You can make
-.Nm
-think that characters other than "m" can end ANSI color escape sequences
-by setting the environment variable
-.Ev LESSANSIENDCHARS
-to the list of characters which can end a color escape sequence.
-And you can make
-.Nm
-think that characters other than the standard ones may appear between
-the ESC and the m by setting the environment variable
-.Ev LESSANSIMIDCHARS
-to the list of characters which can appear.
-.It Fl r | -raw-control-chars
-Causes "raw" control characters to be displayed.
-The default is to display control characters using the caret notation;
-for example, a control-A (octal 001) is displayed as "^A".
-Warning: when the -r option is used,
+Certain characters are special as in the / command:
+.Bl -tag -width Ds
+.It Ic ^N | !
+Display only lines which do NOT match the pattern.
+.It Ic ^R
+Don't interpret regular expression metacharacters;
+that is, do a simple textual comparison.
+.El
+.It Ic :e Op Ar filename
+Examine a new file.
+If the filename is missing, the "current" file (see the :n and :p commands
+below) from the list of files in the command line is re-examined.
+A percent sign (%) in the filename is replaced by the name of the
+current file.
+A pound sign (#) is replaced by the name of the previously examined file.
+However, two consecutive percent signs are simply
+replaced with a single percent sign.
+This allows you to enter a filename that contains a percent sign
+in the name.
+Similarly, two consecutive pound signs are replaced with a single pound sign.
+The filename is inserted into the command line list of files
+so that it can be seen by subsequent :n and :p commands.
+If the filename consists of several files, they are all inserted into
+the list of files and the first one is examined.
+If the filename contains one or more spaces,
+the entire filename should be enclosed in double quotes
+(also see the -" option).
+.It Ic ^X^V | E
+Same as :e.
+Warning: some systems use ^V as a special literalization character.
+On such systems, you may not be able to use ^V.
+.It Ic :n
+Examine the next file (from the list of files given in the command line).
+If a number N is specified, the N-th next file is examined.
+.It Ic :p
+Examine the previous file in the command line list.
+If a number N is specified, the N-th previous file is examined.
+.It Ic :t
+Go to the specified tag.
+.It Ic :x
+Examine the first file in the command line list.
+If a number N is specified, the N-th file in the list is examined.
+.It Ic :d
+Remove the current file from the list of files.
+.It Ic t
+Go to the next tag, if there were more than one matches for the current tag.
+See the \-t option for more details about tags.
+.It Ic T
+Go to the previous tag, if there were more than one matches for the current tag.
+.It Ic = | ^G | :f
+Prints some information about the file being viewed, including its name
+and the line number and byte offset of the bottom line being displayed.
+If possible, it also prints the length of the file,
+the number of lines in the file
+and the percent of the file above the last displayed line.
+.It Ic \-
+Followed by one of the command line option letters (see
+.Sx OPTIONS
+below),
+this will change the setting of that option
+and print a message describing the new setting.
+If a ^P (CONTROL-P) is entered immediately after the dash,
+the setting of the option is changed but no message is printed.
+If the option letter has a numeric value (such as -b or -h),
+or a string value (such as -P or -t),
+a new value may be entered after the option letter.
+If no new value is entered, a message describing
+the current setting is printed and nothing is changed.
+.It Ic \-\-
+Like the \- command, but takes a long option name (see
+.Sx OPTIONS
+below)
+rather than a single option letter.
+You must press ENTER or RETURN after typing the option name.
+A ^P immediately after the second dash suppresses printing of a
+message describing the new setting, as in the \- command.
+.It Ic \-+
+Followed by one of the command line option letters this will reset the
+option to its default setting and print a message describing the new setting.
+(The "\-+X" command does the same thing as "\-+X" on the command line.)
+This does not work for string-valued options.
+.It Ic \-\-+
+Like the \-+ command, but takes a long option name
+rather than a single option letter.
+.It Ic \-!
+Followed by one of the command line option letters, this will reset the
+option to the "opposite" of its default setting and print a message
+describing the new setting.
+This does not work for numeric or string-valued options.
+.It Ic \-\-!
+Like the \-! command, but takes a long option name
+rather than a single option letter.
+.It Ic _
+(Underscore.)
+Followed by one of the command line option letters,
+this will print a message describing the current setting of that option.
+The setting of the option is not changed.
+.It Ic __
+(Double underscore.)
+Like the _ (underscore) command, but takes a long option name
+rather than a single option letter.
+You must press ENTER or RETURN after typing the option name.
+.It Ic +cmd
+Causes the specified cmd to be executed each time a new file is examined.
+For example, +G causes
.Nm
-cannot keep track of the actual appearance of the screen
-(since this depends on how the screen responds to
-each type of control character).
-Thus, various display problems may result,
-such as long lines being split in the wrong place.
-.It Fl S | -chop-long-lines
-Causes lines longer than the screen width to be
-chopped (truncated) rather than wrapped.
-That is, the portion of a long line that does not fit in
-the screen width is not shown.
-The default is to wrap long lines; that is, display the remainder
-on the next line.
-.It Fl s | -squeeze-blank-lines
-Causes consecutive blank lines to be squeezed into a single blank line.
-.It Xo
-.Fl T Ar tagsfile |
-.Fl -tag-file Ns = Ns Ar tagsfile
-.Xc
-Specifies a tags file to be used instead of "tags".
-.It Xo
-.Fl t Ar tag |
-.Fl -tag Ns = Ns Ar tag
-.Xc
-The -t option, followed immediately by a TAG,
-will edit the file containing that tag.
-For this to work, tag information must be available;
-for example, there may be a file in the current directory called "tags",
-which was previously built by
-.Xr ctags 1
-or an equivalent command.
-If the environment variable
-.Ev LESSGLOBALTAGS
-is set, it is taken to be the name of a command compatible with
-.Xr global ,
-and that command is executed to find the tag.
-(See
-.Lk http://www.gnu.org/software/global/global.html ) .
-The -t option may also be specified from within
+to initially display each file starting at the end rather than the beginning.
+.It Ic V
+Prints the version number of
.Nm
-(using the \- command) as a way of examining a new file.
-The command ":t" is equivalent to specifying -t from within
+being run.
+.It Ic q | Q | :q | :Q | ZZ
+Exits
.Nm less .
-.It Fl U | -UNDERLINE-SPECIAL
-Causes backspaces, tabs and carriage returns to be
-treated as control characters;
-that is, they are handled as specified by the -r option.
+.El
.Pp
-By default, if neither -u nor -U is given, backspaces which appear adjacent
-to an underscore character are treated specially:
-the underlined text is displayed
-using the terminal's hardware underlining capability.
-Also, backspaces which appear between two identical characters
-are treated specially:
-the overstruck text is printed
-using the terminal's hardware boldface capability.
-Other backspaces are deleted, along with the preceding character.
-Carriage returns immediately followed by a newline are deleted.
-Other carriage returns are handled as specified by the -r option.
-Text which is overstruck or underlined can be searched for
-if neither -u nor -U is in effect.
-.It Fl u | -underline-special
-Causes backspaces and carriage returns to be treated as printable characters;
-that is, they are sent to the terminal when they appear in the input.
-.It Fl V | -version
-Displays the version number of
-.Nm less .
-.It Fl W | -HILITE-UNREAD
-Like -w, but temporarily highlights the first new line after any
-forward movement command larger than one line.
-.It Fl w | -hilite-unread
-Temporarily highlights the first "new" line after a forward movement
-of a full page.
-The first "new" line is the line immediately following the line previously
-at the bottom of the screen.
-Also highlights the target line after a g or p command.
-The highlight is removed at the next command which causes movement.
-The entire line is highlighted, unless the -J option is in effect,
-in which case only the status column is highlighted.
-.It Fl X | -no-init
-Disables sending the termcap initialization and deinitialization strings
-to the terminal.
-This is sometimes desirable if the deinitialization string does
-something unnecessary, like clearing the screen.
-.It Xo
-.Fl x Ar n Ns , Ns Ar ... |
-.Fl -tabs Ns = Ns Ar n Ns , Ns Ar ...
-.Xc
-Sets tab stops.
-If only one n is specified, tab stops are set at multiples of n.
-If multiple values separated by commas are specified, tab stops are set at
-those positions, and then continue with the same spacing as the last two.
-For example, -x9,17 will set tabs at positions 9, 17, 25, 33, etc.
-The default for n is 8.
-.It Xo
-.Fl y Ar n |
-.Fl -max-forw-scroll Ns = Ns Ar n
-.Xc
-Specifies a maximum number of lines to scroll forward.
-If it is necessary to scroll forward more than n lines,
-the screen is repainted instead.
-The -c or -C option may be used to repaint from the top of
-the screen if desired.
-By default, any forward movement causes scrolling.
-.It Xo
-.Fl z Ar n |
-.Fl -window Ns = Ns Ar n
-.Xc
-Changes the default scrolling window size to n lines.
-The default is one screenful.
-The z and w commands can also be used to change the window size.
-The "z" may be omitted for compatibility with some versions of
-.Nm more .
-If the number
-.Ar n
-is negative, it indicates
-.Ar n
-lines less than the current screen size.
-For example, if the screen is 24 lines, -z-4 sets the
-scrolling window to 20 lines.
-If the screen is resized to 40 lines,
-the scrolling window automatically changes to 36 lines.
-.It Fl -follow-name
-Normally, if the input file is renamed while an F command is executing,
-.Nm
-will continue to display the contents of the original file despite
-its name change.
-If --follow-name is specified, during an F command
-.Nm
-will periodically attempt to reopen the file by name.
-If the reopen succeeds and the file is a different file from the original
-(which means that a new file has been created
-with the same name as the original (now renamed) file),
-.Nm
-will display the contents of that new file.
-.It Fl -no-keypad
-Disables sending the keypad initialization and deinitialization strings
-to the terminal.
-This is sometimes useful if the keypad strings make the numeric
-keypad behave in an undesirable manner.
-.It Fl -use-backslash
-This option changes the interpretations of options which follow this one.
-After the --use-backslash option, any backslash in an option string is
-removed and the following character is taken literally.
-This allows a dollar sign to be included in option strings.
-.It Xo
-.Ar -cc |
-.Fl -quotes Ns = Ns Ar cc
-.Xc
-Changes the filename quoting character.
-This may be necessary if you are trying to name a file
-which contains both spaces and quote characters.
-Followed by a single character, this changes the quote character to that
-character.
-Filenames containing a space should then be surrounded by that character
-rather than by double quotes.
-Followed by two characters, changes the open quote to the first character,
-and the close quote to the second character.
-Filenames containing a space should then be preceded by the open quote
-character and followed by the close quote character.
-Note that even after the quote characters are changed, this option
-remains -" (a dash followed by a double quote).
-.It Fl ~ | -tilde
-Normally lines after end of file are displayed as a single tilde (~).
-This option causes lines after end of file to be displayed as blank lines.
-.It Fl # | -shift
-Specifies the default number of positions to scroll horizontally
-in the RIGHTARROW and LEFTARROW commands.
-If the number specified is zero, it sets the default number of
-positions to one half of the screen width.
-Alternately, the number may be specified as a fraction of the width
-of the screen, starting with a decimal point: .5 is half of the
-screen width, .3 is three tenths of the screen width, and so on.
-If the number is specified as a fraction, the actual number of
-scroll positions is recalculated if the terminal window is resized,
-so that the actual scroll remains at the specified fraction
-of the screen width.
-.It Fl -
-A command line argument of "--" marks the end of option arguments.
-Any arguments following this are interpreted as filenames.
-This can be useful when viewing a file whose name begins with a "-" or "+".
-.It Cm +
-If a command line option begins with +,
-the remainder of that option is taken to be an initial command to
-.Nm less .
-For example, +G tells
-.Nm
-to start at the end of the file rather than the beginning,
-and +/xyz tells it to start at the first occurrence of "xyz" in the file.
-As a special case, +<number> acts like +<number>g;
-that is, it starts the display at the specified line number
-(however, see the caveat under the "g" command above).
-If the option starts with ++, the initial command applies to
-every file being viewed, not just the first one.
-The + command described previously
-may also be used to set (or change) an initial command for every file.
+The following
+four
+commands may or may not be valid, depending on your particular installation.
+.Bl -tag -width XXXX
+.It Ic v
+Invokes an editor to edit the current file being viewed.
+The editor is taken from the environment variable
+.Ev VISUAL ,
+if defined,
+or
+.Ev EDITOR
+if
+.Ev VISUAL
+is not defined,
+or defaults to "vi" if neither
+.Ev VISUAL
+nor
+.Ev EDITOR
+is defined.
+See also the discussion of LESSEDIT under the section on
+.Sx PROMPTS
+below.
+.It Ic \&! Ar shell-command
+Invokes a shell to run the shell-command given.
+A percent sign (%) in the command is replaced by the name of the current file.
+A pound sign (#) is replaced by the name of the previously examined file.
+"!!" repeats the last shell command.
+"!" with no shell command simply invokes a shell.
+The shell is taken from the environment variable
+.Ev SHELL ,
+or defaults to "sh".
+.\" On MS-DOS and OS/2 systems, the shell is the normal command processor.
+.It Ic | <m> Ar shell-command
+<m> represents any mark letter.
+Pipes a section of the input file to the given shell command.
+The section of the file to be piped is between the first line on
+the current screen and the position marked by the letter.
+<m> may also be ^ or $ to indicate beginning or end of file respectively.
+If <m> is . or newline, the current screen is piped.
+.It Ic s Ar filename
+Save the input to a file.
+This only works if the input is a pipe, not an ordinary file.
.El
.Sh LINE EDITING
When entering command line at the bottom of the screen
projects / openbsd / commitdiff