+ /* Looks up the next hop for 'host'. If succesful, stores the next hop
+ * gateway's address (0 if 'host' is on a directly connected network) in
+ * '*next_hop' and a copy of the name of the device to reach 'host' in
+ * '*netdev_name', and returns 0. The caller is responsible for freeing
+ * '*netdev_name' (by calling free()).
+ *
+ * This function may be set to null if it would always return EOPNOTSUPP
+ * anyhow. */
+ int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop,
+ char **netdev_name);
+