[DebianGIS-dev] Bug#579989: Bug#579989: Bug#579989: Tries to dlopen libproj.so instead of libproj.so.0

[Jens Thiele]

"Francesco P. Lovergine" <frankie at debian.org> writes:

> Ok, thanks. Solved in the 1.7.2 branch on svn, due in a few for
> experimental. The reason for skipping by default a usual shlib
> linking is quite obscure to me, but that can be better managed
> by configure. I suspect that is done to avoid depending strictly
> on a specific SONAME, because proj4 API is frozen since ages, but
> anyway that's not the way things are done on Debian.

a) Your solution is IMHO fine (though the upstream naming of the
configure option is misleading, because afaiu libproj is linked
dynamically now and not statically).


b) just as additional comment:

Using dlopen basically allows to move a dependency from build-time to
run-time. The application can provide features depending on wether a
certain library is available at run-time or not. There are certain use
cases where this is required:

Typically interpreter language modules are implemented like that (you
can't build all possible combinations of perl/python/... + modules). Or
"more general" application plugins are done like that. One also can use
dlopen to update a running application (though this has its own problems
and I don't know a real-world example for that one at the moment)

Greetings,
karme