socket的客户端-服务器程序

客户端程序：

通过服务器返回当前的时间和日期。

#include "unp.h"

#include "my_err.h"

int main(int argc, char** argv)

{

int sockfd, n;

char recvline[MAXLINE + 1];

struct sockaddr_in servaddr;

if (argc != 2)

err_quit("usage:a.out<IPaddress>");

if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)

err_sys("socket error");

bzero(&servaddr, sizeof(servaddr));

servaddr.sin_family = AF_INET;

servaddr.sin_port = htons(13);

if (inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0)

err_quit("inet_pton error for %s", argv[1]);

if (connect(sockfd, (SA*)&servaddr, sizeof(servaddr)) < 0)

err_sys("connect error");

while ((n = read(sockfd, recvline, MAXLINE)) > 0)

{

recvline[n] = 0;

if (fputs(recvline, stdout) == EOF)

err_sys("fputs error");

服务器端程序：

获得客户端端的IP和端口号。inet_ntop将套接字地址结构中的32位IP地址转换为一个点分十进制ASCII字符串，调用nthos将16位的端口号从网络字节序转换为主机字节序。

int main(int argc, char** argv)

{

int listenfd, connfd;

socklen_t len;

struct sockaddr_in servaddr, cliaddr;

char buff[MAXLINE];

teme_t ticks;

listenfd = socket(AF_INET, SOCK_STREAM, 0);

bzero(&servaddr, sizeof(servaddr));

servaddr.sin_family = AF_INET;

servaddr.sin_addr.s_addr = htonl(INADDR_ANY);

servaddr.sin_port = htons(13);

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));

crite(connfd, buff, strlen(buff));

close(connfd);

}

}