Description

This article is from the Amiga FAQ, by Ignaz Kellerer with numerous contributions by others.

4.9 How to obtain a pointer to a console's window

   The following function returns the window pointer of a CON window.
It can be executed safely under all versions of the Amiga's OS.
       struct Window *getConWindowPtr(BPTR fh)
       {
         struct Window *w;
         struct FileHandle *cfh;
         struct StandardPacket *sp;
         struct InfoData *id;
         struct MsgPort *mp;
         w = NULL;
         if ((cfh = BADDR(fh))->fh_Type != NULL) {
           if (sp = AllocMem(sizeof (struct StandardPacket),
                             MEMF_PUBLIC | MEMF_CLEAR)) {
             if (id = AllocMem(sizeof (struct InfoData),
                               MEMF_PUBLIC | MEMF_CLEAR)) {
               if (mp = CreatePort(NULL, 0)) {
                 sp->sp_Msg.mn_Node.ln_Name = (char *) &sp->sp_Pkt;
                 sp->sp_Pkt.dp_Link         = &sp->sp_Msg;
                 sp->sp_Pkt.dp_Port         = mp;
                 sp->sp_Pkt.dp_Type         = ACTION_DISK_INFO;
                 sp->sp_Pkt.dp_Arg1         = MKBADDR(id);
                 PutMsg(cfh->fh_Type, &sp->sp_Msg);
                 (void) WaitPort(mp);
                 (void) GetMsg(mp);
                 if (sp->sp_Pkt.dp_Res1)
                   w = (struct Window *) id->id_VolumeNode;
                 DeletePort(mp);
               }
               FreeMem(id, sizeof (struct InfoData));
             }
             FreeMem(sp, sizeof (struct StandardPacket));
           }
         }
         return w;
       }
   Notes:
   * Accessing a console's window directly may interfere with operations
     performed by the CON handler. Be careful!
   * To obtain the window pointer of a CLI's console, pass the
     FileHandle returned by Open("*", MODE_OLDFILE) to the above
     function.
   * The result of the above function may well be NULL, e.g. in case of
     an AUX handler or if an AUTO CON handler is unable to open its
     window.
   * Sending an ACTION_DISK_INFO packet to an AUTO CON handler (2.0+)
     causes its window to lose its special AUTO properties (i.e. it can
     no longer be closed at any time by clicking on its Close gadget),
     as the window pointer returned in id_VolumeNode must remain valid
     from now on.
   * All in all: Don't use this function. :-)
   For more information, please refer to pages 273, 276, 435, 463, 485,
and 629 in "The Amiga Guru Book" (see Manuals).
   Ralph Babel, rbabel@babylon.pfm-mainz.de

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