Official method for determining modular X module path?

[Mike A. Harris]

Andy Ritger wrote:

>>>I think the moduledir variable was discussed on IRC, and a recent
>>>Gentoo install defines moduledir, but a user reported that it is
>>>not defined on Fedora Core 5 RC1.  Does the moduledir definition
>>>in the pkgconfig *.pc files come from the Xorg modular build, or is
>>>that something distribution maintainers will need to handle manually?
>>>
>>>I'm nervous that this could be the kind of thing that would be easy
>>>for a distro to overlook, and would only be exposed when someone
>>>tried to install a 3rd party driver.
>>
>>It depends from distribution to distribution.  For Ubuntu and Debian,
>>this will only be installed if you install xserver-xorg-dev, which also
>>installs all the development headers.
> 
> That may be problematic for users -- I expect many people won't
> install the xserver-xorg-dev package, and it doesn't seem like that
> should be necessary inorder for 3rd party installation tools to
> know the module path.

The distribution packaging of the particular driver should query
the value of 'moduledir' from pkgconfig at package build time, and
use that.  Alternatively, if one set of binaries is to be used,
which are built outside of any package management system, but which
will be packaged in a variety of package management systems such
as rpm, dpkg, emerge, etc. then these packages "source" will actually
be binary driver tarballs or similar, and the packaging can still
query moduledir at package creation time to know where that distro
keeps the module directory.

That way, even one set of binaries can end up being installed to
different locations on different distributions.  There should never
be a need to have a development package installed at runtime to
query though, that should always be done at build time, either
software build time, or software 'packaging' time  (which for OSS
drivers is simultaneous of course, but which might be different
times and people for non-OSS).

The only possible problem I can think of, is for generic tarballs
or other generic installation mechanisms that do not use any
package management system at all.  Those should only be used
by the IHVs, distribution packagers, or community packagers
themselves however for the creation of working packages for the
given distro using the accepted package management system for
that distro. ;o)

Direct use of generic tarballs or custom distribution neutral
installation scripts should be discouraged.  ;o)

If there was a demand for this however, perhaps the X server could
have some options added to it to permit querying of the location of
the moduledir and other paths.  Perhaps "X -query(moduledir)" or
something.  Any thoughts?