Do Modular and parameterise coding

In C++ you may use RAII[^]. Do initialization in the constructor, do some cleanup in the destructor. Take special care of exceptions in the destructor.
 
In C you must tell the client of your code to follow the protocol: call first some invented Init(...) function, then at the end some invented Release(...) function. Both functions are part of your library and do what you require in your question.
Cheers
Andi