Re: Problems with data files

[Ralf Wildenhues]

Hello Ganesh,

* Ganesh Kundapur wrote on Mon, May 26, 2008 at 10:43:50AM CEST:
>   My directory structure is
>   Game
>    - Makefile.am
>    - src
>      - Makefile.am
>    - inc
>    - data
>      <some files>
>      - audio
>     - Makefile.am
> 
> Toplevel Makefile.am contains
>    datadir = /usr/share/game/data

Note that this setting here has several problems:

- It will not propagate from toplevel Makefile.am to other Makefiles.
In order to override a variable globally, do something like
   AC_SUBST([datadir], [$value])

in configure.ac.

- Actually, datadir is predefined by Autoconf, and while you can
override it, it is not such a good idea, because then the output of
  ./configure --help

will not tell the truth, for example.  You could set gamedir in
configure.ac, for example, and use that in the Makefile.am files.

- Your setting is absolute, instead of relative to, say, ${prefix}.
No installation directory should be passed in absolute, because your
users may want to (and have good reason to!) override it.  For example,
I may want to use "--prefix=$HOME/local" and expect all files to be
installed below my home directory, because that's where I have write
privileges.

A better setting would be "'${datarootdir}'", which, incidentally, is
the default set by Autoconf.

"make distcheck" ensures that you do not define absolute directories.

- I wonder whether you should not touch the setting at all, and instead
just teach your users to
  ./configure --datadir=/usr/share/game/data

which will most likely do the right thing.  (Use --datarootdir if you
want docdir, infodir, localedir, and mandir to be adjusted as well.)

Please see
<http://www.gnu.org/software/automake/manual/html_node/Standard-Directory-Variables.html>
<http://www.gnu.org/software/autoconf/manual/standards/Directory-Variables.html>
and references therein for more information on this.

> When i configure, Makefile will be created under src, data directories but
> not under data/audio directory. Makefile wont be created even if i put a
> entry under SUBDIRS

That's likely because you haven't listed that Makefile as
AC_CONFIG_FILES in configure.ac.

> in toplevel Makefile.am as
> game/Makefile.am
> ---------------------------
> datadir = /usr/share/game/data
> 
> SUBDIR = src \
>                 data \
>                 data/audio
> 
> and when i run make, i'm getting the fallowing errors due to absence of the
> Makefile under data/audio directory

This is likely just a followup error of above.

Hope that helps.

Cheers,
Ralf