回显服务器的程序

服务器程序：

int main()

{

int      listenfd, connnfd;

pid_t  childpid;

socklen_t  clilen;

struct sockaddr_in  cliaddr, servaddr;

listenfd = socket(AF_INET, SOCK_STREAM, 0);

bzero(&servaddr, sizeof(servaddr));

servaddr.family = AF_INET;

servaddr.sin_addr.s_addr = htonl(INADDR_ANY);

servaddr.sin_port = htons(9877);

bind(listenfd, (struct sockaddr*)&servaddr, sizeof(struct sockaddr));

listen(listenfd, 5);

for(;;)

{

clilen = sizeof(cliaddr);

connfd = accept(listenfd, (struct sockaddr*)&cliaddr, &clilen);

if((childpid = fork()) == 0)

{

close(listenfd);

str_echo(connfd);

exit(0);

}

}

close(connfd);

}

void str_echo(int sockfd);

{

size_t n;

char   buff[MAXFILE];

again:

while((n=read(sockfd, buff, MAXFILE)) > 0)

write(sockfd, buf, n);

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

goto again;

else if(n < 0)

err_sys("str_echo error");

}

客户端：

int main()

{

int sockfd;

struct sockaddr_in  servaddr;

sockfd = socket(AF_INET, SCOK_STREAM, 0);

bzero(&servaddr, sizeof(servaddr));

servaddr.family = AF_INET;

servaddr.sin_port = htons(9877);

inet_pton(AF_INET, argv[1], &servaddr.sin_addr);

connect(sockfd, (struct sockaddr)&servaddr, sizeof(struct sockaddr));

str_cli(stdin, sockfd);

exit(0);

}

str_cli(FILE* fp, int sockfd)

{

char sendline[MAXLINE], recvline[MAXLINE];

while(fgets(sendline, MAXLINE, fp) != NULL)

{

write(sockfd, sendline, srelen(sendline));

if(readline(sockfd, recvline, MAXLINE) == 0)

printf("error");

fputs(recvline, stdout);

}

}