Re: pkg-config and autoconf

[Ralf Corsepius]

On Sat, 2003-08-09 at 11:17, lsiden wrote:
> When examining the Pango distribution as an example, I see there is a
> configure.in which uses PKG_CHECK_MODULES (and thus indirectly uses
> pkg-config) but no configure.ac.  Is this what I need to do in order to
> use PKG_CHECK_MODULES, forego configure.ac in favor of configure.in? 
No. With 2.57, the names "configure.ac".and "configure.in" can both be
used.

> The syntax of configure.in looks much more verbose.
>From info autoconf:

 Previous versions of Autoconf promoted the name `configure.in',
which is somewhat ambiguous (the tool needed to process this file is not
described by its extension), and introduces a slight confusion with
`config.h.in' and so on (for which `.in' means "to be processed by
`configure'").  Using `configure.ac' is now preferred.

In a nutshell: configure.ac|in's are to be processed by autoconf.
'*.in's in general, however are being processed by other tools
(typically configure, rsp. config.status)

Using the name configure.ac enables you to apply file extension based
processing (eg. suffix-rules in Makefiles) to configure.ac|ins.

Ralf