#include	"unp.h"intmain(int argc, char **argv){	int					sockfd;	void				sig_alrm(int);	struct itimerval	val;	struct sockaddr_in	servaddr;	if (argc != 2)		err_quit("usage: tcpcli <IPaddress>");	sockfd = Socket(AF_INET, SOCK_STREAM, 0);	bzero(&servaddr, sizeof(servaddr));	servaddr.sin_family = AF_INET;	servaddr.sin_port = htons(SERV_PORT);	Inet_pton(AF_INET, argv[1], &servaddr.sin_addr);		/* Set interval timer to go off before 3WHS completes */	Signal(SIGALRM, sig_alrm);	val.it_interval.tv_sec  = 0;	val.it_interval.tv_usec = 0;	val.it_value.tv_sec  = 0;	val.it_value.tv_usec = 50000;	/* 50 ms */	if (setitimer(ITIMER_REAL, &val, NULL) == -1)		err_sys("setitimer error");	Connect(sockfd, (SA *) &servaddr, sizeof(servaddr));	str_cli(stdin, sockfd);		/* do it all */	exit(0);}voidsig_alrm(int signo){	exit(0);}