Want function to get ADIOS2 library version at run time

[eschnett]

I would like to have a function (in the C API) that returns the ADIOS2 version number. This will allow the Julia wrapper to inquire the current version by calling the C API (or reading a global variable), and make run-time decisions based on this, e.g. whether certain functionality is available.

A C #define would not be good enough because these are not available in a shared library.

[pnorbert]

Please see #3633 and comment

[ax3l]

@pnorbert I would like the same function for C++ please (if there is none already). For the same reasons, if there is a runtime function to query which opt-in functionality is available (SST, BP5, Compressors, MPI, etc.) that would be awesome, too.

In openPMD-api, we have something similar:
https://github.com/openPMD/openPMD-api/blob/0.15.1/src/version.cpp
https://github.com/openPMD/openPMD-api/blob/0.15.1/src/config.cpp#L31-L65

And in Python we return a dictionary with the compiled-in functionality:
https://github.com/openPMD/openPMD-api/blob/0.15.1/src/binding/python/openPMD.cpp#L111-L117

[pnorbert]

Note to myself: Maybe also add a function to get the supported features that are turned on in the particular adios library.