XtAddEventHandler(3)		 XT FUNCTIONS		  XtAddEventHandler(3)



NAME
       XtAddEventHandler, XtAddRawEventHandler, XtRemoveEventHandler,
       XtRemoveRawEventHandler, XtInsertEventHandler, XtInsertRawEventHandler
       - add and remove event handlers

SYNTAX
       void XtAddEventHandler(Widget w, EventMask event_mask, Boolean nonmask-
	      able, XtEventHandler proc, XtPointer client_data);

       void XtAddRawEventHandler(Widget w, EventMask event_mask, Boolean non-
	      maskable, XtEventHandler proc, XtPointer client_data);

       void XtRemoveEventHandler(Widget w, EventMask event_mask, Boolean non-
	      maskable, XtEventHandler proc, XtPointer client_data);

       void XtRemoveRawEventHandler(Widget w, EventMask event_mask, Boolean
	      nonmaskable, XtEventHandler proc, XtPointer client_data);

       void XtInsertEventHandler(Widget w, EventMask event_mask, Boolean non-
	      maskable, XtEventHandler proc, XtPointer client_data, XtListPo-
	      sition position);

       void XtInsertRawEventHandler(Widget w, EventMask event_mask, Boolean
	      nonmaskable, XtEventHandler proc, XtPointer client_data, XtList-
	      Position position);

       typedef enum { XtListHead, XtListTail } XtListPosition;

ARGUMENTS
       client_data

		 Specifies additional data to be passed to the client's event
		 handler.

       event_mask

		 Specifies the event mask for which to call or unregister this
		 procedure.

       nonmaskable

		 Specifies a Boolean value that indicates whether this proce-
		 dure should be called or removed on the nonmaskable events
		 (GraphicsExpose, NoExpose, SelectionClear, SelectionRequest,
		 SelectionNotify, ClientMessage, and MappingNotify).

       proc	 Specifies the procedure that is to be added or removed.

       w	 Specifies the widget for which this event handler is being

		 registered.

       position  Specifies when the event handler is to be called relative to

		 other previously registered handlers.

DESCRIPTION
       The XtAddEventHandler function registers a procedure with the dispatch
       mechanism that is to be called when an event that matches the mask
       occurs on the specified widget.	If the procedure is already registered
       with the same client_data, the specified mask is ORed into the existing
       mask.  If the widget is realized, XtAddEventHandler calls XSelectInput,
       if necessary.

       The XtAddRawEventHandler function is similar to XtAddEventHandler
       except that it does not affect the widget's mask and never causes an
       XSelectInput for its events.  Note that the widget might already have
       those mask bits set because of other nonraw event handlers registered
       on it.

       The XtRemoveRawEventHandler function stops the specified procedure from
       receiving the specified events.	Because the procedure is a raw event
       handler, this does not affect the widget's mask and never causes a call
       on XSelectInput.

       XtInsertEventHandler is identical to XtAddEventHandler with the addi-
       tional position argument. if position is XtListHead, the event handler
       is registered to that it will be called before any event handlers that
       were previously registered for the same widget.	If position is XtList-
       Tail, the event handler is registered to be called after any previously
       registered event handlers. If the procedure is already registered with
       the same client_data value, the specified mask augments the existing
       mask and the procedure is repositioned in the list.

       XtInsertRawEventHandler is similar to XtInsertEventHandler except that
       it does not modify the widget's event mask and never causes an XSelect-
       Input for the specified events. If the procedure is already registered
       with the same client_data value, the specified mask augments the exist-
       ing mask and the procedure is repositioned in the list.

SEE ALSO
       XtAppNextEvent(3Xt), XtBuildEventMask(3Xt)
       X Toolkit Intrinsics - C Language Interface
       Xlib - C Language X Interface



X Version 11			  libXt 1.0.5		  XtAddEventHandler(3)

NAME - SYNTAX - ARGUMENTS - DESCRIPTION - SEE ALSO -