A handle to a persistent procedure or an otherwise active procedure on the call stack.
By default, the AVM searches the external procedure that created the current control-frame for the event procedure to handle an ActiveX control event. This method allows you to specify alternative procedure (.p and .w) files to search for the event handler.
When the AVM receives an ActiveX event, it searches for the event handler in order of the most recent procedure added to the search list and ends the search with the external procedure that created the control-frame. You can override an existing procedure by adding a different one to the search list. The AVM always uses the event handler in the most recently added procedure.
If the method succeeds in adding the procedure to the list, it returns TRUE. Otherwise, it returns FALSE.
