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


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

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

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

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

void XtRemoveAllCallbacks(Widget w, String callback_name,



Specifies the callback procedure.


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


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


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.


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.


X Toolkit Intrinsics − C Language Interface
Xlib − C Language X Interface


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