Re: Checking versions and defining macros

[Jason Curl]

Ralf Wildenhues wrote:
> Hello Jason,
>
> let's please limit replies to the autoconf list, thanks.
>   
Sorry, I wanted to check for various solutions for all the packages, not 
just autoconf.
> * Jason Curl wrote on Wed, Mar 05, 2008 at 06:47:04AM CET:
>   
> > To achieve my goals, I've borrowed some of the internals of the auto*  
> > tools (and libtool). I'd like to somehow check the version of the  
> > autotools during "autoreconf" time and include macros specific to a  
> > particular version. If I see a version that I haven't tested with, then  
> > I'd like to print a warning that something needs to be looked at (i.e.  
> > update my macros). This will allow me especially to upgrade to  
> > libtool-2.2 and play with it, while knowing it will always work with 
> > 1.5.24.
> >
> > A summary of what I've had to hack:
> > AC_CHECK_LIB: borrowed from here for the Solaris networking features
> > AC_CHECK_DECL: Disable printing, to encapsulate in my own scripts
> > AC_PROG_LD: Would die if it couldn't find LD, rather than allow my  
> > configure.ac to provide an alternate
> >     
>
> Not sure what your question is.  Autoconf minimum version can be
> required with AC_PREREQ, its exact version is
> m4_defn([m4_PACKAGE_VERSION]).  Automake minimum version can be required
> with AM_INIT_AUTOMAKE.  Libtool minimum version can be required with
> LT_PREREQ (starting from 2.2).  To rule out earlier versions, you can
> see whether LT_PREREQ is defined: m4_ifdef([LT_PREREQ], [...]).
>   
If I have autoconf 2.59, I would like to use macro A. But if I have 
autoconf 2.61, then I'd like to use macro B instead. Ideally, they would 
be the same name, but might have slightly different definitions, 
especially if I start to use the internals.

I would do this, because I've had to modify and borrow implementations 
from libtool 1.5.24. As autotools don't guarantee internal APIs as being 
stable, I would warn when autotools are too new, or use a different 
implementation.

There are two development environments I use. One is older than the 
other and when I start using internal APIs, they may become 
incompatible, unless I can include macro A for version A of autotools 
and macro B for version B of autotools.

I hope I make more sense this time.

Thanks,
Jason.