Site Macro Directory

[Mark D. Roth]

As someone who maintains several different autoconf macros and several
different software packages that share the macros, I'd like to find a
better way of distributing my macros for use.  Currently, I need to
copy each macro I maintain into the aclocal.m4 file of each package
that needs to use the macro.  This is a bit inconvenient and can
introduce problems keeping all of the copies in sync.

I propose that we modify autoconf to have a system-wide site macro
directory (analogous to emacs's site-lisp directory or perl's
site_perl directory) where third-party macros can be installed and
maintained.  The idea is that I'd publish my autoconf macros as
independent packages, which people could download and install into
their system's site macro directory (which would be something like
"${prefix}/share/autoconf/site_macros").  If one of my packages uses
one of these macros, I'd put a note in the README file that says "if
you need to regenerate configure, you'll need autoconf (available from
...) and macro package foo (available from ...)".

The only semantic problem that I see with this is how autoconf would
decide which files in the site macro directory to read.  I can see two
possible ways for autoconf to handle this:

  * It could read them all.  This would be the easiest for people to
    use, but it might cause namespace conflicts or potential speed
    problems if a large number of macros are defined.

  * We could add a macro called AC_INCLUDE (or something like that) to
    include individual macro files (analogously to cpp's `#include').
    For example, package maintainers could use "AC_INCLUDE([foo.m4])"
    to include the file "${prefix}/share/autoconf/site_macros/foo.m4".

Anyway, if we could introduce something like this, it would make it
much easier for people to share autoconf macros, which IMHO would make
autoconf a much more useful tool.  Please let me know what you think.

-- 
Mark D. Roth <address@hidden>
http://www.feep.net/~roth/