if_delmulti
error = if_delmulti(ifp, &ifr->ifr_addr);
int if_delmulti(if_t, struct sockaddr *);
error = if_delmulti(parent,
(void)if_delmulti(ifp_p, (struct sockaddr *)&mc->mc_addr);
error = if_delmulti(priv->ifp,
retval = -if_delmulti(ndev, &addr._sockaddr);