hpux man page for xttimercallbackproc

XtTimerCallbackProc()													     XtTimerCallbackProc()

Name
  XtTimerCallbackProc - interface definition for procedure invoked when timeouts expire.

Synopsis
  typedef void (*XtTimerCallbackProc)(XtPointer, XtIntervalId *);
	  XtPointer client_data;      XtIntervalId *id;

Inputs
  client_data
	    Specifies the data that was registered with this procedure.

  id	    Specifies the ID returned when this procedure was registered.

Description
  An  XtTimerCallbackProc is registered in a call to XtAppAddTimeOut(), and is invoked when the specified number of milliseconds elapse.  The
  client_data argument is data registered with the procedure in the call to XtAppAddTimeOut(), and the id argument is the value  returned  by
  that function.

  A  timer callback is called once, and then is automatically removed.	If you want a callback to be called repeatedly, re-register the call-
  back each time it is called,

Example
  The following XtTimerCallbackProc is from the xmh program.  It re-registers itself so that it will be called repeatedly.  Note that it uses
  its client_data argument to supply the application context so that it can re-register itself.

     /*ARGSUSED*/
     static void NeedToCheckScans(client_data, id)
	 XtPointer client_data;
	 XtIntervalId *id;	     /* unused */
     {
	 int i;
	 if (!subProcessRunning) {
	     DEBUG("[magic toc check ...")
	     for (i = 0; i < numScrns; i++) {
		 if (scrnList[i]->toc)
		     TocRecheckValidity(scrnList[i]->toc);
		 if (scrnList[i]->msg)
		     TocRecheckValidity(MsgGetToc(scrnList[i]->msg));
	     }
	     DEBUG(" done]0)
	 }
	 (void) XtAppAddTimeOut((XtAppContext)client_data,
				(unsigned long) app_resources.rescan_interval,
				NeedToCheckScans, client_data);
     }

  This procedure is initially registered with the following code:

	 if (app_resources.rescan_interval > 0) {
	     app_resources.rescan_interval *= 60000;
	     (void) XtAppAddTimeOut(appCtx,
		      (unsigned long) app_resources.rescan_interval,
		      NeedToCheckScans, (XtPointer)appCtx);
	 }

See Also
  XtAppAddTimeOut(1), XtRemoveTimeOut(1).

Xt - Event Handling													     XtTimerCallbackProc()