Re: Getting srcdir in script executed using m4_esyscmd in AC_INIT

[Bob Friesenhahn]

On Sun, 3 Jan 2021, Zack Weinberg wrote:
> The trick here is that these shell commands will be executed when you
> run autoconf, *not* when you run configure.  And you have to run
> autoconf with the current working directory equal to the top of the
> source tree *anyway*.  So the answer is ". will be the top of the
> source tree."  This is why automake's rule for regenerating configure
> from configure.ac does `cd $(top_srcdir) && $(AUTOCONF)`.

Yes, it seemed like that should be the case.  Just before you read 
your email I realized that the problem was that my script was executed 
in two different ways, and the older way was executing it (while 
executing configure) in the current directory.

> Autoconf itself does something similar and it works reliably:
> (quoting https://git.savannah.gnu.org/cgit/autoconf.git/tree/configure.ac#n22)
>
> AC_INIT([GNU Autoconf],
>    m4_esyscmd([build-aux/git-version-gen .tarball-version]),
>    [bug-autoconf@gnu.org])
>
> I presume this is *not* working reliably for you or you wouldn't have
> asked the question, so could you go into a little more detail about
> how you invoked autoconf and/or configure and what went wrong?

The above is what I was using as an example. :-)

GraphicsMagick needs to substitute quite a lot more version info so I 
was also doing this in the body of configure.ac:

# Source file containing package/library versioning information.
. ${srcdir}/version.sh

What I did was to make the same script accept arguments.  Sourcing the 
script is ok but not if it does not compute the same values.

Thank you for your help.

Bob
--
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
Public Key,     http://www.simplesystems.org/users/bfriesen/public-key.txt