网络编程

实验一 SOCKET基本编程

参考源代码： 客户端程序如下： #include #include #include #include #include #define PORT 1234

#define MAXDATASIZE 100 int

main(int argc, char *argv[]) { int fd, numbytes;

char buf[MAXDATASIZE]; char rvbuf[MAXDATASIZE]; struct hostent *he; struct sockaddr_in server; if (argc != 2) { printf(\ exit(-1);

}

if ((he =gethostbyname(argv[1])) == NULL) { perror(\ exit(1);

}

if ((fd =socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror(\

exit(1);

1

}

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

memcpy(&server.sin_addr,he->h_addr,sizeof(struct in_addr));

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

}

struct sockaddr_in localaddr; socklen_t len = sizeof(localaddr);

getsockname(fd,(struct sockaddr *)&localaddr,&len); printf(\

Localip

and

is: %s:%d\\n\

struct sockaddr_in peeraddr; socklen_t lenp = sizeof(peeraddr);

getpeername(fd, (struct sockaddr *)&peeraddr,&lenp); printf(\

Peerip

and

is: %s:%d\\n\ close(fd);

}

服务器端程序如下： #include #include #include #include #include #define PORT 1234 #define BACKLOG 1

Localport

Peerport

2

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

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

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

exit(-1);

}

int opt=SO_REUSEADDR;

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)

3

{ perror(\

exit(-1);

} close(connectfd);

}

close(listenfd); }

4

实验二 服务器与单客户的连接处理

参考源代码： 客户端程序如下： #include #include #include #include #define PORT 1234

#define MAXDATASIZE 1000 int main(int argc,char * argv[]) {

int fd,numbytes;

char buf[MAXDATASIZE]; struct hostent * he; struct sockaddr_in server; int i=1; if(argc!=2) {

printf(\ \\n\ exit(-1); }

if((he=gethostbyname(argv[1]))==NULL){ perror(\

exit(-1);

}

if((fd=socket(AF_INET,SOCK_STREAM,0))==-1){ perror(\

exit(1);

}

bzero(&server,sizeof(server));

5