网络编程(3)

bzero(&server,sizeof(server)); server.sin_family=AF_INET; server.sin_port=htons(PORT);

server.sin_addr=*((struct in_addr *)he->h_addr);

if(connect(fd,(struct sockaddr *)&server,sizeof(struct sockaddr))==-1) { perror(\

exit(1);

}

if((numbytes=recv(fd,buf,MAXDATASIZE,0))==-1) { perror(\

exit(1);

}

buf[numbytes]='\\0';

printf(\ printf(\ scanf(\

if((numbytes=send(fd,buf,strlen(buf),0))==-1) { perror(\

exit(1);

}

while(i){

printf(\ scanf(\ if(strlen(buf)<1) i=0 ;

if((numbytes=send(fd,buf,strlen(buf),0))==-1) { perror(\

exit(1);

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}

if((numbytes=recv(fd,buf,MAXDATASIZE,0))==-1) { perror(\

exit(1);

}

buf[numbytes]='\\0';

printf(\ printf(\ } close(fd); }

服务器端程序如下： #include #include #include #include #include #include #include #define PORT 1234 #define BACKLOG 2 #define MAXCHARSIZE 1000

void process_client(int connectfd,struct sockaddr_in client); int main(void) {

int listenfd,connectfd; struct sockaddr_in server,client; int sin_size;

int opt=SO_REUSEADDR; pid_t pid;

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if((listenfd=socket(AF_INET,SOCK_STREAM,0))==-1) {

perror(\ exit(-1); }

setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt)); bzero(&server,sizeof(server)); server.sin_family=AF_INET; server.sin_port=htons(PORT);

server.sin_addr.s_addr=htonl(INADDR_ANY);

if(bind(listenfd,(struct sockaddr *)&server,sizeof(struct sockaddr))==-1) { perror(\

exit(-1);

}

if(listen(listenfd,BACKLOG)==-1) { perror(\

exit(-1);

}

sin_size=sizeof(struct sockaddr_in); while(1){

if((connectfd=accept(listenfd,(struct sockaddr *) &client,&sin_size))==-1){ perror(\ exit(-1);

}

if((pid=fork())>0){ close(connectfd) ; continue; }

else if(pid==0){

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close(listenfd);

process_client(connectfd,client); exit(1); } else {

perror(\ error.\\n\

exit(0);

} }

close(listenfd); }

void process_client(int connectfd,struct sockaddr_in client){ char recvbuf[MAXCHARSIZE]; char sendbuf[MAXCHARSIZE]; char client_name[MAXCHARSIZE]; int recvlen,i;

printf(\ send(connectfd,\ recvlen=recv(connectfd,client_name,MAXCHARSIZE,0); if(recvlen==0){ close(connectfd);

printf(\ return; }

else if(recvlen<0){

close(connectfd);

printf(\ return; }

client_name[recvlen]='\\0';

printf(\

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while(recvlen=recv(connectfd,recvbuf,MAXCHARSIZE,0)){ recvbuf[recvlen]='\\0';

printf(\ message:%s\\n\ for(i=0;i

send(connectfd,sendbuf,strlen(sendbuf),0);

} /*while*/

printf(\ close(connectfd); }

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