XtAddCallback(3Xt)		XT FUNCTIONS		   XtAddCallback(3Xt)



NAME
  XtAddCallback, XtAddCallbacks, XtRemoveCallback, XtRemoveCallbacks,
  XtRemoveAllCallbacks - add and remove callback procedures

SYNTAX
  void XtAddCallback(w, callback_name, callback, client_data)
	Widget w;
	String callback_name;
	XtCallbackProc callback;
	XtPointer client_data;

  void XtAddCallbacks(w, callback_name, callbacks)
	Widget w;
	String callback_name;
	XtCallbackList callbacks;

  void XtRemoveCallback(w, callback_name, callback, client_data)
	Widget w;
	String callback_name;
	XtCallbackProc callback;
	XtPointer client_data;

  void XtRemoveCallbacks(w, callback_name, callbacks)
	Widget w;
	String callback_name;
	XtCallbackList callbacks;

  void XtRemoveAllCallbacks(w, callback_name)
	Widget w;
	String callback_name;

ARGUMENTS

  callback  Specifies the callback procedure.

  callbacks Specifies the null-terminated list of callback procedures and
	    corresponding client data.

  callback_name
	    Specifies the callback list to which the procedure is to be
	    appended or deleted.

  client_data
	    Specifies the argument that is to be passed to the specified pro-
	    cedure when it is invoked by XtCallbacks or NULL, or the client
	    data to match on the registered callback procedures.

  w	    Specifies the widget.

DESCRIPTION
  The XtAddCallback function adds the specified callback procedure to the
  specified widget's callback list.

  The XtAddCallbacks add the specified list of callbacks to the specified
  widget's callback list.

  The XtRemoveCallback function removes a callback only if both the procedure
  and the client data match.

  The XtRemoveCallbacks function removes the specified callback procedures
  from the specified widget's callback list.

  The XtRemoveAllCallbacks function removes all the callback procedures from
  the specified widget's callback list.

SEE ALSO
  XtCallCallbacks(3Xt)
  X Toolkit Intrinsics - C Language Interface
  Xlib - C Language X Interface