how do I solve version conflict that occurs due to multiple version of library inclusion in Linux

Question

In my project, I am trying to use two libraries those are already compiled and generated. Let us say liba.so(our own library created sometime back) and libssl.so.10.(It is available in the Linux).

Now liba.so is having dependency libcurl.so.3 & libssl.so.10 is having dependency libcurl.so.4 (latest)

Both libcurl.so.3 and libcurl.so.4 are available in the system.

Hence When I try to use both of them in my project, I am getting version conflict. Is it expected? If yes, how do I solve this problem?

Is there any way to modify liba.so dependency with latest libcurl.so.4 without building this library again? Or do I need to build liba.so again with latest libcurl.so.4?

Thanks for your help

Answer 1

Hence When I try to use both of them in my project, I am getting version conflict. Is it expected? If yes, how do I solve this problem?

There are two solutions.

First, you would carry around the versions of libcurl.so & libssl.so you want to use. You would then use the linker's rpath or LD_LIBRARY_PATH to ensure you load the shared objects you included.

Second, you would build your liba.so to statically link against libcurl and libssl.

If you are working on Android, then number two is your choice. That's because OpenSSL is included on Android, zygote loads it, and you always get the downlevel version 0.9.8 after the fork from zygote.

On Android, you would even need to build a wrapper shared object if all you wanted was a modern OpenSSL like 1.0.1 (that looks a lot like what you are experiencing with libcurl.so.3 and libcurl.so.4).