[mapguide-internals] Versioning for Linux so's

[Trevor Wekel]

Hi all,

Currently, we mark all of our shared libraries as "so.7.0.0" and we have not changed this from release to release.

From the versioning discussion of Libtool http://www.gnu.org/software/libtool/manual/libtool.html#Versioning, -version-info implies very specific rules on interface compatibility.  Since our interfaces change from release to release, ie. not compatible, it may be more appropriate to use -release instead of -version-info.  Libraries of the same release are compatible for linking/patching purposes (2.2.0, 2.2.0).  Libraries with different release versions (2.2.0, 2.2.1, 2.3.0) are not.  I think this is more in line with how we develop MapGuide.

From what I can tell, all we need to change is -version-info 7:0:0 in the various Makefile.am scripts to -release 2.2.0.  We may be able to parameterize this change with a declaration in the top level Makefile.am.

Please let me know if anyone has any concerns with this approach.

Regards,
Trevor