XtAddCallback(3Xt)                   SysV                   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;
           caddr_t 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;
           caddr_t 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
               procedure 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