LRESULT CALLBACK WndProcedure(HWND hWnd, UINT Msg,
               WPARAM wParam, LPARAM lParam)
{
    switch(Msg)
    {
    case WM_DESTROY:
        // user wants to exit
        PostQuitMessage(WM_QUIT);
        break;
    default:
        // Hand off unprocessed messages to DefWindowProc
        return DefWindowProc(hWnd, Msg, wParam, lParam);
    }
    
    return 0;
}