Question

When my MFC DLL is loaded a class is instantiated in dllmain. How do I free the resources allocated for this when the DLL is unloaded or its process completes? Will this be done automatically by the system? I am using Visual Studio 2008. Thanks.

Answer 1

in you dll main function just handle a case for the DLL_PROCESS_DETACH.

BOOL WINAPI DllMain( HMODULE hDll, DWORD dwReason, PVOID pvReserved ) {
  switch ( dwReason ) {
    case DLL_PROCESS_DETACH:
      // the dll is being detached, do you clean up here
      break;
  }
}

Keep in mind that some things are not possible inside of DllMain(), so you want to keep whatever yo do there very quick and simple.