2. /*./client serv_ip serv_port */
    3. #include "net.h"
    5. void usage (char *s)
    6. {
    7.     printf ("\n%s serv_ip serv_port", s);
    8.     printf ("\n\t serv_ip: server ip address");
    9.     printf ("\n\t serv_port: server port(>5000)\n\n");
    10. }
    12. int main (int argc, char **argv)
    13. {
    14.     int fd = -1;
    16.     int port = -1;
    17.     struct sockaddr_in sin;
    19.     if (argc != 3) {
    20.         usage (argv[0]);
    21.         exit (1);
    22.     }
    23.     /* 1. 创建socket fd */
    24.     if ((fd = socket (AF_INET, SOCK_STREAM, 0)) < 0) {
    25.         perror ("socket");
    26.         exit (1);
    27.     }
    29.     port = atoi (argv[2]);
    30.     if (port < 5000) {
    31.         usage (argv[0]);
    32.         exit (1);
    33.     }
    34.     /*2.连接服务器 */
    36.     /*2.1 填充struct sockaddr_in结构体变量 */
    37.     bzero (&sin, sizeof (sin));
    39.     sin.sin_family = AF_INET;
    40.     sin.sin_port = htons (port);    //网络字节序的端口号
    41. #if 0
    42.     sin.sin_addr.s_addr = inet_addr (SERV_IP_ADDR);
    43. #else
    44.     if (inet_pton (AF_INET, argv[1], (void *) &sin.sin_addr) != 1) {
    45.         perror ("inet_pton");
    46.         exit (1);
    47.     }
    48. #endif
    50.     if (connect (fd, (struct sockaddr *) &sin, sizeof (sin)) < 0) {
    51.         perror ("connect");
    52.         exit (1);
    53.     }
    55.     printf ("Client staring...OK!\n");
    56.     /*3. 读写数据 */
    57.     char buf[BUFSIZ];
    58.     int ret = -1;
    59.     while (1) {
    60.         bzero (buf, BUFSIZ);
    61.         if (fgets (buf, BUFSIZ - 1, stdin) == NULL) {
    62.             continue;
    63.         }
    64.         do {
    65.             ret = write (fd, buf, strlen (buf));
    66.         } while (ret < 0 && EINTR == errno);
    68.         if (!strncasecmp (buf, QUIT_STR, strlen (QUIT_STR))) {    //用户输入了quit字符
    69.             printf ("Client is exiting!\n");
    70.             break;
    71.         }
    72.     }
    74.     /*4.关闭套接字 */
    75.     close (fd);
    76. }