if (setsockopt(fd, IPPROTO_IPV6, join ? IPV6_ADD_MEMBERSHIP : IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
avahi_log_warn("%s failed: %s", join ? "IPV6_ADD_MEMBERSHIP" : "IPV6_DROP_MEMBERSHIP", strerror(errno));
return -1;
if (setsockopt(fd, IPPROTO_IPV6, join ? IPV6_ADD_MEMBERSHIP : IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
avahi_log_warn("%s failed: %s", join ? "IPV6_ADD_MEMBERSHIP" : "IPV6_DROP_MEMBERSHIP", strerror(errno));
return -1;