rn_delete
rnh->rnh_deladdr = rn_delete;
rnh->rnh_deladdr = rn_delete;
x = (struct radix_node *)rn_delete(rn + 2, NULL, rnh);
struct radix_node *rn_delete(const void *, const void *, struct radix_head *);
rh->rnh_deladdr = rn_delete;
x = (struct radix_node *)rn_delete(rn + 2, NULL, rnh);
rn = rn_delete(&ke->pfrke_sa, &mask, head);
rn = rn_delete(&ke->pfrke_sa, NULL, head);