getting started

[Rob Benton]

Hey everybody, I'm just getting started with all the autotools and I was 
looking for a little help.  I've been over all I could find about the 
autoconf and m4 docs but I'm not quite clear and how to write my own 
macros and what format they should be in.  All the autoconf docs refer 
to the m4 docs on the subject of writing macros.  Using just m4 syntax 
in the aclocal.m4 file didn't seem to work.

Just an example of what I've tried to do today.  I wanted to write a 
macro that checks the CXX compiler and set some other variable, say 
LDFLAGS, differently depending on if 'g++' or 'xlC_r' was found.  This 
is what I put in each file:


configure.ac:
-------------
AC_SUBST([LDFLAGS], [AC_TEST_ME([CXX])])

aclocal.m4:
-----------
AC_DEFUN([AC_TEST_ME],
         [ifelse($1, [g++], [-shared],
            $1, [xlC_r], [-G])]
      )




But only the literal "CXX" gets passed in to my macro and I don't know 
how to extract its value if that's possible.  So am I going about this 
the right way?