XtCallCallbacks(3Xt)RISC/os Reference Manual XtCallCallbacks(3Xt)



NAME
     XtCallCallbacks, XtHasCallbacks - process callbacks

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

     w         Specifies the widget.

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

     The XtHasCallbacks function first checks to see if the wid-
     get 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












                         Printed 1/24/91  1 September 1988 Page 1