#include	"unp.h"intmain(int argc, char **argv){	int					sockfd;	struct linger		ling;	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);	Connect(sockfd, (SA *) &servaddr, sizeof(servaddr));	str_cli(stdin, sockfd);		/* do it all */	ling.l_onoff = 1;	ling.l_linger = 0;	Setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling));	exit(0);}