87     int tunnel = socket(AF_INET6, SOCK_DGRAM, 0);  in get_tunnel()  local
89     setsockopt(tunnel, SOL_SOCKET, SO_REUSEADDR, &flag, sizeof(flag));  in get_tunnel()
91     setsockopt(tunnel, IPPROTO_IPV6, IPV6_V6ONLY, &flag, sizeof(flag));  in get_tunnel()
100     while (bind(tunnel, (sockaddr *)&addr, sizeof(addr))) {  in get_tunnel()
112         int n = recvfrom(tunnel, packet, sizeof(packet), 0,  in get_tunnel()
121     connect(tunnel, (sockaddr *)&addr, addrlen);  in get_tunnel()
122     return tunnel;  in get_tunnel()
188     int tunnel;  in main()  local
189     while ((tunnel = get_tunnel(argv[2], argv[3])) != -1) {  in main()
199         fcntl(tunnel, F_SETFL, O_NONBLOCK);  in main()
203             send(tunnel, parameters, sizeof(parameters), MSG_NOSIGNAL);  in main()
223                 send(tunnel, packet, length, MSG_NOSIGNAL);  in main()
235             length = recv(tunnel, packet, sizeof(packet), 0);  in main()
270                         send(tunnel, packet, 1, MSG_NOSIGNAL);  in main()
284         close(tunnel);  in main()