How to use your own DllMain in MFC Dll's

If you want to write your own DllMain in a MFC Dll then you have to do some real cool stuff because MFC internally calls its DllMain. If you try to write your own DllMain, you get a linker error saying "DllMain already defined". To resolve this issue you have to copy "DllModul.cpp" from MFC source directory to your project directory and include it in your own project.

//////////////////////////////////////////////
// export DllMain for the DLL
 
extern "C"
BOOL WINAPI DllMain(HINSTANCE hInstance, 
                    DWORD dwReason, 
                    LPVOID /*lpReserved*/)
{
  //.................
  // Add your own initialisation Here
  if (dwReason == DLL_PROCESS_ATTACH)
  {
    BOOL bResult = FALSE;
 
#ifdef _AFXDLL
    // wire up resources from core DLL
    AfxCoreInitModule();
#endif
    ...
    ... 
    ...
    return TRUE;
}