Configure check for smbwrapper

[Tim Potter]

> > OK, here's a bit of autoconf to do most of the check.  Unfortunately the
> > AC_DEFINE(LD_PRELOAD) doesn't seem to do anything to include/config.h.
> 
> That's right, you must add `#undef LD_PRELOAD' (or HAVE_LD_PRELOAD,
> according to your macro :-) to acconfig.h

Thought I did that...  I'll try it again.

> > AC_TRY_COMMAND($CC $CFLAGS -c conf-preload.c)
> > AC_TRY_COMMAND($CC $LDSHFLAGS $CFLAGS -o libconf-preload1.so conf-preload1.c)
> > AC_TRY_COMMAND($CC $LDSHFLAGS $CFLAGS -o libconf-preload2.so conf-preload2.c)
> > AC_TRY_COMMAND($CC $CFLAGS $CPPFLAGS -o conftest conf-preload.o ./libconf-preload1.so)
> 
> AC_TRY_COMMAND does not exist (or is not documented) in autoconf 2.12; 
> is this a new extension?  Why don't you just run the commands one
> after another? (>/dev/null 2>&1, of course :-)

Good idea.  I found the AC_TRY_COMMAND macro in acgeneral.m4 of my
autoconf 2.12 installation.

> > LD_PRELOAD=./libconf-preload2.so; export LD_PRELOAD
> > AC_TRY_COMMAND(conftest > conf.out)
> 
> Never trust that `.' is in the PATH; better run ./conftest.  BTW, why
> don't you just redirect the output to /dev/null?

Oops - debugging statement left in.

> Since you're within AC_CACHE_CHECK, don't print results yourself, and
> don't do the final action within the cache block, otherwise it won't
> take place if the value is cached already.  So, I'd suggest:

[...]

I've made the changes you suggested and it all works now.  Thanks!  Do you
think it is worth moving the C programs into the source/tests directory?
It might make the configure.in a bit cleaner.


Tim.

> -- 
> Alexandre Oliva  http://www.dcc.unicamp.br/~oliva  aoliva@{acm.org}
> oliva@{dcc.unicamp.br,gnu.org,egcs.cygnus.com,samba.org.au}
> Universidade Estadual de Campinas, SP, Brasil
>