unix网络编程卷一: 第五章:服务器反射客户端消息(一)

服务器代码(tcpsrv01.c)：

#include "unp.h"

int main(int argc, char **argv)

{

intlistenfd, connfd;

pid_tchildpid;

socklen_tclilen;

struct sockaddr_incliaddr, servaddr;

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(SERV_PORT);

Bind(listenfd, (SA *) &servaddr,sizeof(servaddr));

Listen(listenfd, LISTENQ);

for ( ; ; ) {

clilen =sizeof(cliaddr);

connfd = Accept(listenfd, (SA *) &cliaddr, &clilen);

if ( (childpid = Fork()) ==0) { /* child process *///复制一个子进程处理

Close(listenfd);/* close listening socket */

str_echo(connfd);/* process the request */ //具体处理函数

exit(0);

}

Close(connfd);/* parent closes connected socket */

}

}

服务器代码(str_echo.c):

#include "unp.h"

void str_echo(int sockfd)

{

ssize_tn;

charbuf[MAXLINE];

again:

while ( (n = read(sockfd, buf, MAXLINE)) >0) //从客户端读取消息

Writen(sockfd, buf, n);//反射消息

if (n <0 && errno == EINTR)

goto again;

elseif (n < 0)

err_sys("str_echo: read error");

}

客户端代码(tcpcli01.c):

#include "unp.h"

int main(int argc, char **argv)

{

intsockfd;

struct sockaddr_inservaddr;

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 */  //客户端具体处理函数

exit(0);

}

客户端代码(str_cli.c):

#include "unp.h"

void str_cli(FILE *fp, int sockfd)

{

charsendline[MAXLINE], recvline[MAXLINE];

while (Fgets(sendline, MAXLINE, fp) !=NULL) { //从输入设备读取信息

Writen(sockfd, sendline, strlen(sendline));//发送给服务器

if (Readline(sockfd, recvline, MAXLINE) ==0) //从服务器读取返回信息

err_quit("str_cli: server terminated prematurely");

Fputs(recvline, stdout);//输出到显示设备

}

}