Unix网络编程

#include        "unp.h"
#include        <time.h>

int
main(int argc, char **argv)
{
        int                                     listenfd, connfd;
        socklen_t                       len;
        struct sockaddr_in      servaddr, cliaddr;
        char                            buff[MAXLINE];
        time_t                          ticks;
        listenfd = Socket(AF_INET, SOCK_STREAM, 0);
        bzero(&servaddr, sizeof(servaddr));
        servaddr.sin_family      = AF_INET;
        inet_pton(AF_INET,"222.27.254.151",&servaddr.sin_addr.s_addr);
        servaddr.sin_port        = htons(13);   /* daytime server */
        Bind(listenfd, (SA *) &servaddr, sizeof(servaddr));
        Listen(listenfd, LISTENQ);
        for ( ; ; ) {
                len = sizeof(cliaddr);
                connfd = Accept(listenfd, (SA *) &cliaddr, &len);
                printf("connection from %s, port %d\n",
                           Inet_ntop(AF_INET, &cliaddr.sin_addr, buff, sizeof(buff)),
                           ntohs(cliaddr.sin_port));

        ticks = time(NULL);
        snprintf(buff, sizeof(buff), "%.24s\r\n", ctime(&ticks));
        Write(connfd, buff, strlen(buff));

                Close(connfd);
        }
}

以上代码是简单的服务器程序，实现的是输出时间和访问者的ip地址，源代码没有与网卡的ip地址绑定，使用inet_pton函数能够实现ip地址的绑定，权做练习。

关于出现  Bind error: Address already in use 的问题

能够采用  lsof -i：13（端口号）查找进程，进而kill掉便可。