= socket(domain, type, protocol);
if (lfd == -1){
cout strerror...SO_REUSEADDR, &opt, sizeof(opt));
if (ret == -1){
cout strerror...ret = bind(lfd, ser_addr, ser_len);
if (ret == -1){
cout strerror...ret = connect(cfd, addr, addrlen);
if (ret == -1){
cout strerror...SIGCHLD, &act, NULL);
if (ret == -1){
cout strerror