XtAddCallback, XtAddCallbacks, XtRemoveCallback, XtRemoveCallbacks, XtRemoveAllCallbacks - add and remove

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.

       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.

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

XtCallCallbacks(3)
       XToolkitIntrinsics-CLanguageInterfaceXlib-CLanguageXInterface

X Version 11                                       libXt 1.2.1                                  XtAddCallback(3)

       #include <X11/Intrinsic.h>

       void XtAddCallback(Widget w, const char *callback_name, XtCallbackProc callback, XtPointer client_data);

       void XtAddCallbacks(Widget w, const char *callback_name, XtCallbackList callbacks);

       void   XtRemoveCallback(Widget   w,   const   char  *callback_name,  XtCallbackProc  callback,  XtPointer
              client_data);

       void XtRemoveCallbacks(Widget w, const char *callback_name, XtCallbackList callbacks);

       void XtRemoveAllCallbacks(Widget w, const char *callback_name);