Document the grep workaround.

* doc/autoconf.texi (Limitations of Usual Tools) <grep>: Document
the bug.

Signed-off-by: Eric Blake <eblake@redhat.com>

diff --git a/ChangeLog b/ChangeLog
index 6a614bc7cac9f27b08f6b31d311f5c537be3cca4..fd7d06842a1c9727e739ca80fb1a6a786df544e1 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2010-05-12  Eric Blake  <eblake@redhat.com>
+
+       Document the grep workaround.
+       * doc/autoconf.texi (Limitations of Usual Tools) <grep>: Document
+       the bug.
+
 2010-05-12  Mark Hessling  <mark@rexx.org>  (tiny change)
 
        Work around QNX4 grep bug.

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 39e11a50cbf4853bd420a96daefe2f82b1e2dca0..ff62eac92c33d0025c74d618c5eb62f0bae6d572 100644 (file)
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -17829,6 +17829,10 @@ redirect the standard output and standard error (in case the file
 doesn't exist) of @code{grep} to @file{/dev/null}.  Check the exit
 status of @code{grep} to determine whether it found a match.
 
+The QNX4 implementation fails to count lines with @code{grep -c '$'},
+but works with @code{grep -c '^'}.  Another alternative for counting
+lines is to use @code{wc -l}.
+
 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.