#include <OS2.h>                                             #include <OS2.h>
#include <StdLib.h>                                          #include <StdLib.h>

#define Main main                                            #define Main main

Main ()                                                      Main ()
{                                                            {
  HAB Shell_handle = WinInitialize (0);                        HAB Shell_handle = WinInitialize (0);
  if (!Shell_handle) DosExit (EXIT_PROCESS, -1);
                                                               if (Shell_handle)
  HMQ Msg_queue = WinCreateMsgQueue (Shell_handle, 0);         {
  if (!Msg_queue) DosExit (EXIT_PROCESS, -1);                    HMQ Msg_queue = WinCreateMsgQueue (Shell_handle, 0);

  WinMessageBox (HWND_DESKTOP, NULLHANDLE,                       if (Msg_queue)
                 "Hello World!", "", 0, 0);                    {
                                                                   WinMessageBox (HWND_DESKTOP, NULLHANDLE,
  WinDestroyMsgQueue (Msg_queue);                                                 "Hello World!", "", 0, 0);
  WinTerminate (Shell_handle);
                                                                   WinDestroyMsgQueue (Msg_queue);
  return 0;                                                        WinTerminate (Shell_handle);
}                                                                }
                                                                 else
                                                                 {
                                                                   DosExit (EXIT_PROCESS, -1);
                                                                 }
                                                               }
                                                               else
                                                               {
                                                                 DosExit (EXIT_PROCESS, -1);
                                                               }

                                                               return 0;
                                                             }
