memcpy(&in6, ai->ai_addr, sizeof in6);
memcpy(&mreq.ipv6mr_multiaddr, &in6.sin6_addr, sizeof mreq.ipv6mr_multiaddr);
mreq.ipv6mr_interface = in6.sin6_scope_id;
memcpy(&in6, ai->ai_addr, sizeof in6);
memcpy(&mreq.ipv6mr_multiaddr, &in6.sin6_addr, sizeof mreq.ipv6mr_multiaddr);
mreq.ipv6mr_interface = in6.sin6_scope_id;