06-using-flex.patch

[Akim Demaille]

Index: ChangeLog
from  Akim Demaille  <address@hidden>
        * doc/autoconf.texi (Particular Programs): Some notes on the
        portability of Flex.

Index: doc/autoconf.texi
--- doc/autoconf.texi Sun, 15 Oct 2000 09:30:12 +0200 akim (ace/16_autoconf.t 
1.61.2.80 666)
+++ doc/autoconf.texi Sun, 15 Oct 2000 21:21:57 +0200 akim (ace/16_autoconf.t 
1.61.2.80 666)
@@ -2646,6 +2646,28 @@ @node Particular Programs, Generic Progr
 the base of the file name that the lexer generates; usually
 @file{lex.yy}, but sometimes something else.  These results vary
 according to whether @code{lex} or @code{flex} is being used.
+
+You are encouraged to use Flex in your sources, since it is both more
+pleasant to use than plain Lex, and it is more portable.  But in order
+to ensure portability, you must either provide a function @code{yywrap},
+or if you don't use it (i.e., your scanner has no @samp{#include}-like
+feature), simply include a @samp{%noyywrap} statement in the scanner's
+source.  Once this done, the scanner is portable (well, unless
address@hidden felt free to use nonportable constructs) and does not depend
+on any library.  In this case, and in this case only, it is suggested
+that you use this Autoconf snippet:
+
address@hidden
+AC_PROG_LEX
+if test "$LEX" != flex; then
+  LEX="$missing_dir/missing flex"
+  AC_SUBST(LEX_OUTPUT_ROOT, lex.yy)
+  AC_SUBST(LEXLIB, '')
+fi
address@hidden example
+
+The shell script @command{missing} can be found in the Automake
+distribution.
 @end defmac

 @defmac AC_PROG_LN_S