Its __int64 and thats final. If you want to recast it inside your function go ahead, but the interface is set in stone. Sorry if thats a bit blunt but there has to be one set interface or Ill end up rewriting the test program for every entry. If I do it for one person ill end up doing it for everyone.
If you have need of a specific header file state what you need, don't ask me to open it up for no reason. The only exception that comes to mind are the headers for OpenMP or for DirectX(HLSL). I see no reason that any other headers shodul be needed, but liek I said, if you need a specific header file, ask first.