XtCallCallbacks(3Xt)

     NAME
          XtCallCallbacks, XtCallCallbackList, XtHasCallbacks -
          process callbacks

     SYNTAX
          void XtCallCallbacks(w, callback_name, call_data)
                Widget w;
                String callback_name;
                XtPointer call_data;

          void XtCallCallbackList(w, callbacks, call_data)
                Widget w;
                XtCallbackList callbacks;
                XtPointer call_data;

          typedef enum {XtCallbackNoList, XtCallbackHasNone,
          XtCallbackHasSome} XtCallbackStatus;

          XtCallbackStatus XtHasCallbacks(w, callback_name)
                Widget w;
                String callback_name;

     ARGUMENTS
          callback_name
                    Specifies the callback list to be executed or
                    checked.

          call_data Specifies a callback-list specific data value to
                    pass to each of the callback procedure in the
                    list.

          callbacks Specifies the callback list to be executed.

          w         Specifies the widget.

     DESCRIPTION
          The XtCallCallbacks function calls each procedure that is
          registered in the specified widget's callback list.

          If callbacks is not NULL, XtCallCallbackList calls each of
          the callback procedures in the list, passing client data and
          call_data. The callbacks parameter must specify the contents
          of a widget or object resource declared with representation
          type XtRCallback.

          The XtHasCallbacks function first checks to see if the
          widget has a callback list identified by callback_name.  If
          the callback list does not exist, XtHasCallbacks returns
          XtCallbackNoList.  If the callback list exists but is empty,
          it returns XtCallbackHasNone.  If the callback list exists
          and has at least one callback registered, it returns
          XtCallbackHasSome.
     SEE ALSO
          XtAddCallback(3Xt)
          X Toolkit Intrinsics - C Language Interface
          Xlib - C Language X Interface