Opensource library API?

Welcome @kokta!

Yes, there is also the open source implementation at Advanced Do It Yourself Memory Reading In EVE Online, including a guide to illustrate the approach to memory reading in EVE Online.

About your choice of C: I have not tried using C with this library. The library linked above is based on .NET, you can call it from C like other .NET libraries. Since the source code is not too complex, another option is to translate the code to C.