This example uses the default window procedure, called by WinDefWindowProc, for default processing of non supported window messages.

#define INCL_WINWINDOWMGR       /* Window Manager Functions     */
#include <os2.h>

MRESULT GenericWndProc(HWND  hwnd, ULONG  ulMsgid, MPARAM mpParam1,
                      MPARAM mpParam2)
{
switch(ulMsgid)
   {
   /*
   .
   . process user supported messages
   .
   */

   default:
     return (WinDefWindowProc(hwnd, ulMsgid, mpParam1, mpParam2));
   }
}