Callback used to let the listener free resources associated with the listener. This callback is to notify the listener that it is safe to remove any data allocated for this listener. After this callback is called, the listener will no longer be called. Because the listener is updated as the state of the system changes, routes added or updated by RouteStatus will not be removed after this (Removed) is called. It may therefore be necessary to cleanup data "orphaned" by the removal of the listener (since the RouteStatus call will not be called again for this listener). This callback may be NULL to ignore notification of removal.
|