Sync printf family return value with ISO C which specifies that

these functions return a negative value on failure.
OK doug@ deraadt@

diff --git a/lib/libc/stdio/printf.3 b/lib/libc/stdio/printf.3
index 6b724da..e94ccf4 100644 (file)
--- a/lib/libc/stdio/printf.3
+++ b/lib/libc/stdio/printf.3
@@ -1,4 +1,4 @@
-.\"    $OpenBSD: printf.3,v 1.73 2015/06/03 16:26:04 millert Exp $
+.\"    $OpenBSD: printf.3,v 1.74 2015/10/13 12:25:04 millert Exp $
 .\"
 .\" Copyright (c) 1990, 1991, 1993
 .\"    The Regents of the University of California.  All rights reserved.
@@ -33,7 +33,7 @@
 .\"
 .\"     @(#)printf.3   8.1 (Berkeley) 6/4/93
 .\"
-.Dd $Mdocdate: June 3 2015 $
+.Dd $Mdocdate: October 13 2015 $
 .Dt PRINTF 3
 .Os
 .Sh NAME
@@ -642,7 +642,7 @@ a field; if the result of a conversion is wider than the field width, the
 field is expanded to contain the conversion result.
 .Sh RETURN VALUES
 For all these functions if an output or encoding error occurs, a value
-of \-1 is returned.
+less than 0 is returned.
 .Pp
 The
 .Fn printf ,