rn_match
x = rn_match(v_arg, head);
*rn_match(void *, struct radix_node_head *),
rnh->rnh_matchaddr = rn_match;
rnh->rnh_matchaddr = rn_match;
x = rn_match(v_arg, head);
*rn_match(void *, struct radix_node_head *),
*rn_match __P((void *, struct radix_node_head *)),