Function if

engine/dlib/src/dlib/socket_posix.cpp:253–258

        }
#if !defined(DM_IPV6_UNSUPPORTED)
        else if (IsSocketIPv6(socket))
        {
            struct in6_addr inaddr;
            memcpy(&inaddr, IPv6(&address), sizeof(struct in6_addr));
            result = setsockopt(socket, IPPROTO_IP, IP_MULTICAST_IF, (char *) &inaddr, sizeof(inaddr));
        }
#endif // no ipv6
        else
        {