shared obj versioning

surlac · 06-25-2017, 06:02 PM

I've noticed that some cross toolchains create shared objects with version appended (e.g. libgeos on Android built with NDK produces "libgeos-3.6.1.so", but on x86-64 it is "libgeos.so").
Why this versioning is needed on Android? And what controls this kind of behavior?

AwesomeMachine · 06-25-2017, 07:50 PM

There is usually a lib.so and a lib.version.so, or several. It is controlled by the library itself. Sometimes there are different versions of a library on the same system. So, in order for users to check if the correct version is present, version numbers are attached. Programs can read the version from within the library.

Many times the various versions are symlinks to one file. Many times when one is missing a library, he can just make a symlink from the base library with the correct version number.