Function AddMembership

engine/dlib/src/dlib/socket_posix.cpp:206–237

    }

    Result AddMembership(Socket socket, Address multi_addr, Address interface_addr, int ttl)
    {
#if defined(__EMSCRIPTEN__)
        return RESULT_AFNOSUPPORT;
#else
        int result = -1;
        if (IsSocketIPv4(socket))
        {
            assert(multi_addr.m_family == DOMAIN_IPV4 && interface_addr.m_family == DOMAIN_IPV4);
            struct ip_mreq group;
            group.imr_multiaddr.s_addr = *IPv4(&multi_addr);
            group.imr_interface.s_addr = *IPv4(&interface_addr);
            result = setsockopt(socket, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *)&group, sizeof(group));
            if (result == 0)
            {
                uint8_t ttl_byte = (uint8_t) ttl;
                result = setsockopt(socket, IPPROTO_IP, IP_MULTICAST_TTL, (char *)&ttl_byte, sizeof(ttl_byte));
            }
        } else if (IsSocketIPv6(socket))
        {
            assert(multi_addr.m_family == DOMAIN_IPV6 && interface_addr.m_family == DOMAIN_IPV6);
            assert(false && "Interface membership not implemented for IPv6");
        }
        else
        {
            dmLogError("Failed to add interface membership, unsupported address family!");
            return RESULT_AFNOSUPPORT;
        }

        return result == 0 ? RESULT_OK : NATIVETORESULT(DM_SOCKET_ERRNO);
#endif
    }

    Result SetMulticastIf(Socket socket, Address address)
    {