* doc/autoconf.texi (Shell Substitutions): Mention the MSYS

shell issue with double-quoted command substitutions of native
commands.
Reported to MSYS by Mark Cave-Ayland, to Autoconf by Keith
Marshall.

diff --git a/ChangeLog b/ChangeLog
index 50c31d256d861390630341fcac53c6e81d099b3f..6b66c8ddbb25fea6c1cb5f47d3196915bad435a6 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2006-04-06  Ralf Wildenhues  <Ralf.Wildenhues@gmx.de>
 
+       * doc/autoconf.texi (Shell Substitutions): Mention the MSYS
+       shell issue with double-quoted command substitutions of native
+       commands.
+       Reported to MSYS by Mark Cave-Ayland, to Autoconf by Keith
+       Marshall.
+
        * Makefile.maint (sc_cast_of_argument_to_free): Do not fail when
        no file matches the glob, discard the warning, set `nullglob'.
        (syntax-check): Likewise.

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 220f0527c01652794cd3c9261f5230eebcc90eb2..94ac534cdbc89bc93540f9f8461c9d582c8c4200 100644 (file)
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -10975,6 +10975,17 @@ $ @kbd{test -z "`cd /`" && pwd}
 @noindent
 The result of @samp{foo=`exit 1`} is left as an exercise to the reader.
 
+The MSYS shell leaves a stray byte in the expansion of a double-quoted
+command substitution of a native program, if the end of the substution
+is not aligned with the end of the double quote.  This may be worked
+around by inserting another pair of quotes:
+
+@example
+$ @kbd{echo "`printf 'foo\r\n'` bar" > broken}
+$ @kbd{echo "`printf 'foo\r\n'`"" bar" | cmp - broken}
+- broken differ: char 4, line 1
+@end example
+
 
 @item $(@var{commands})
 @cindex $(@var{commands})