From 08bb0fe5b409a4cd86620f114f4366e62b76ef49 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Tue, 29 Dec 2020 22:48:02 -0800 Subject: doc: modernize grep discussion --- doc/autoconf.texi | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/doc/autoconf.texi b/doc/autoconf.texi index 5e17280e..d09aba70 100644 --- a/doc/autoconf.texi +++ b/doc/autoconf.texi @@ -19291,8 +19291,8 @@ dir=`AS_DIRNAME(["$file"])` # This is more portable. @item @command{egrep} @c ------------------ @prindex @command{egrep} -Posix 1003.1-2001 no longer requires @command{egrep}, -but many hosts do not yet support the Posix +Although Posix stopped requiring @command{egrep} in 2001, +a few traditional hosts (notably Solaris) do not support the Posix replacement @code{grep -E}. Also, some traditional implementations do not work on long input lines. To work around these problems, invoke @code{AC_PROG_EGREP} and then use @code{$EGREP}. @@ -19477,8 +19477,8 @@ expr: More than one '\(' was used. @item @command{fgrep} @c ------------------ @prindex @command{fgrep} -Posix 1003.1-2001 no longer requires @command{fgrep}, -but many hosts do not yet support the Posix +Although Posix stopped requiring @command{fgrep} in 2001, +a few traditional hosts (notably Solaris) do not support the Posix replacement @code{grep -F}. Also, some traditional implementations do not work on long input lines. To work around these problems, invoke @code{AC_PROG_FGREP} and then use @code{$FGREP}. @@ -19519,7 +19519,7 @@ portable scripts should not combine @option{-c} with @option{-l}, as Posix does not allow this. Some of the options required by Posix are not portable in practice. -Don't use @samp{grep -q} to suppress output, because many @command{grep} +Don't use @samp{grep -q} to suppress output, because traditional @command{grep} implementations (e.g., Solaris) do not support @option{-q}. Don't use @samp{grep -s} to suppress output either, because Posix says @option{-s} does not suppress output, only some error messages; @@ -19537,7 +19537,7 @@ Some traditional @command{grep} implementations do not work on long input lines. On AIX the default @code{grep} silently truncates long lines on the input before matching. -Also, many implementations do not support multiple regexps +Also, traditional implementations do not support multiple regexps with @option{-e}: they either reject @option{-e} entirely (e.g., Solaris) or honor only the last pattern (e.g., IRIX 6.5 and NeXT). To work around these problems, invoke @code{AC_PROG_GREP} and then use -- cgit v1.2.1