* @node: ptr to node structure of interest (or NULL, if none)
* @handle_node_down: routine to invoke when node fails
* @usr_handle: argument to pass to routine when node fails
* @nodesub_list: adjacent entries in list of subscriptions for the node
*/
* @node: ptr to node structure of interest (or NULL, if none)
* @handle_node_down: routine to invoke when node fails
* @usr_handle: argument to pass to routine when node fails
* @nodesub_list: adjacent entries in list of subscriptions for the node
*/