bug#7773: (lack of) config.h description in manual

[Ralf Wildenhues]

As part of addressing Automake bug#7766 and bug#7773, I'm pushing the
following in Karl's name, to the maint branch.

Cheers,
Ralf

2011-01-08  Karl Berry  <address@hidden>
            Eric Blake  <address@hidden>

        docs: reference defining directories in amhello node.
        * doc/automake.texi (amhello Explained): Point to Autoconf
        manual for how to convert directory values into macros.
        (Optional): Fix grammar nit.

diff --git a/doc/automake.texi b/doc/automake.texi
index 43ad581..c63dbf3 100644
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -1736,6 +1736,11 @@ amhello Explained
 The only important effect of this second line is therefore to install
 @file{README} during @code{make install}.
 
+One thing not covered in this example is accessing the installation
+directory values (@pxref{Standard Directory Variables}) from your
+program code, that is, converting them into defined macros.  For this,
address@hidden Directories,,, autoconf, The Autoconf Manual}.
+
 
 @node Generalities
 @chapter General ideas
@@ -2905,7 +2910,7 @@ Optional
 of Automake required the use of @code{AM_CONFIG_HEADER}
 (@pxref{Macros}); this is no longer the case.
 
-As for @code{AC_CONFIG_FILES} (@pxref{Requirements}), parts of the
+As with @code{AC_CONFIG_FILES} (@pxref{Requirements}), parts of the
 specification using shell variables will be ignored as far as
 cleaning, distributing, and rebuilding is concerned.