if(getsockopt(sock, IPPROTO_IP, IP_MTU, (void *)&ip_mtu, &ip_mtu_len)) {
logger(DEBUG_TRAFFIC, LOG_ERR, "getsockopt(IP_MTU) on %s (%s) failed: %s", n->name, n->hostname, sockstrerror(sockerrno));
if(getsockopt(sock, IPPROTO_IP, IP_MTU, (void *)&ip_mtu, &ip_mtu_len)) {
logger(DEBUG_TRAFFIC, LOG_ERR, "getsockopt(IP_MTU) on %s (%s) failed: %s", n->name, n->hostname, sockstrerror(sockerrno));