hpux man page for xtappnextevent

XtAppNextEvent()														  XtAppNextEvent()

Name
  XtAppNextEvent - dispatch timer and alternate input event and return the next X event.

Synopsis
  void XtAppNextEvent(app_context, event_return)
	 XtAppContext app_context;
	 XEvent *event_return;

Inputs
  app_context Specifies the application context.

Outputs
  event_return
	      Returns the dequeued event structure.

Description
  If  there  is an X event pending on any of the Displays in app_context, XtAppNextEvent() returns that event in event_return.	Otherwise, it
  flushes the X output buffer of each Display, and if there is a background work procedure  registered	(see  XtAppAddWorkProc()),  XtAppNex-
  tEvent()  calls it and starts over by checking for pending events.  If there are no pending events and no work procedures, XtAppNextEvent()
  blocks while waiting for input on any of the Display connections, activity on any of the alternate  input  sources  registered  with	XtAp-
  pAddInput(), or the expiration of any timers registered with XtAppAddTimeOut().

  If there is activity on an alternate input source or if a timeout interval elapses, XtAppNextEvent() calls the callback that was registered
  with the input source or with the timer.  If an X event occurs, XtAppNextEvent() removes that event  from  the  queue  and  returns  it  in
  event_return.

Usage
  Programs  rarely need this much control over the event dispatching mechanism.  Most programs use XtAppMainLoop().  If you want to process a
  single X, input, or timer event, consider XtAppProcessEvent().

See Also
  XtAppAddInput(1), XtAppAddTimeOut(1), XtAppAddWorkProc(1), XtAppMainLoop(1), XtAppPeekEvent(1), XtAppPending(1), XtAppProcessEvent(1),
  XtDispatchEvent(1).

Xt - Event Handling														  XtAppNextEvent()