2007-08-21  Stepan Kasal  <address@hidden>
	    Ralf Wildenhues  <address@hidden>

	* doc/autoconf.texi (Defining Directories): Mention
	AM_CPPFLAGS, as the way to modify CPPFLAGS when using Automake.

Index: doc/autoconf.texi
===================================================================
RCS file: /cvsroot/autoconf/autoconf/doc/autoconf.texi,v
retrieving revision 1.1165
diff -u -r1.1165 autoconf.texi
--- doc/autoconf.texi	20 Aug 2007 21:29:36 -0000	1.1165
+++ doc/autoconf.texi	21 Aug 2007 19:20:03 -0000
@@ -19170,11 +19170,18 @@
 @end example
 
 @noindent
-or create a dedicated header file:
+If you are using Automake, you should use @code{AM_CPPFLAGS} instead:
 
 @example
-DISTCLEANFILES = datadir.h
-datadir.h: Makefile
+AM_CPPFLAGS = -DDATADIR='"$(datadir)"'
address@hidden example
+
address@hidden
+Alternatively, create a header file:
+
address@hidden
+DISTCLEANFILES = myprog-paths.h
+myprog-paths.h: Makefile
         echo '#define DATADIR "$(datadir)"' >$@@
 @end example