C / C++ / MFC

//------------------------------------------------------------------------
//------------------------------------------------------------------------
HWND CKickerDlg::FindThruCopyData()
{
   HWND hWndIce    = NULL;
   m_hGlobalIceWnd = NULL;

   COPYDATASTRUCT cds;
   cds.dwData      = 0;
   cds.cbData      = 0;
   cds.lpData      = NULL;
   WPARAM wParam   = WPARAM(m_hWnd);
   LPARAM lParam   = LPARAM(&cds);

   int nTimeout    = 5000;
   int nTime       = 0;
   int nInterval   = 200;

   ::SendNotifyMessage(HWND_BROADCAST, WM_COPYDATA, wParam, lParam);

   do
   {
      // keep the message pump pumping
      MSG msg;
      if (::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) 
      {
         TranslateMessage(&msg);
         DispatchMessage(&msg);
      }

      // get the global hwnd set by our own processing of wm_copydata
      hWndIce = m_hGlobalIceWnd;
      // if our hWnd is still NULL, sleep again
      if (hWndIce == NULL)
      {
         Sleep(nInterval);
         nTime += nInterval;
      }
   } while (hWndIce == NULL && nTime <= nTimeout);

   return hWndIce;
}