nfs_send
int nfs_send (struct socket *, struct sockaddr *, struct mbuf *,
error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep);
error = nfs_send(so, rep->r_nmp->nm_nam, m, rep);
error = nfs_send(slp->ns_so, nd->nd_nam2, m, NULL);