Retrieving Instance Data from Window Words

       case WMP_MYMESSAGE:
            hFrame=WinQueryWindow(hwnd,
                                  QW_PARENT,
                                  FALSE);
            MyStruct=WinQueryWindowULong(hFrame,
                                         QWL_USER);
            <Perform action>
            return((MRESULT)0);
            break;
              :