if_delmulti
error = if_delmulti(ifp, &ifr->ifr_addr);
int if_delmulti(struct ifnet *, struct sockaddr *);
if_delmulti(ifp, (struct sockaddr *)mc->mc_ifma);
if_delmulti(ifp_p, (struct sockaddr *)&sdl); /* ignore error */
error = if_delmulti(priv->ifp,
if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);
if_delmulti(ifma->ifma_ifp, ifma->ifma_addr);