http://blog.sina.com.cn/s/blog_87766e4a0100yp7a.html

1、 基于多线程实现一个服务器和一个客户端实现全双工通信

服务器端创建两个线程：一个用于接收客户端发送过来的信息；一个用来给客户端发送信息。

客户端也创建两个线程：一个用于接收服务器端发送过来的信息；一个用来给服务器端发送信息。

 

2、 示例代码

服务器端的代码client.c

#include <sys/types.h>

#include <sys/socket.h>

#include <stdio.h>

#include <stdlib.h>

#include <errno.h>

#include <string.h>

#include <unistd.h>

#include <netinet/in.h>

#define SERVPORT 3333

#define BACKLOG 10                 //请求队列中的最大请求数

#define MAX_CONNECTED_NO 10  //最大是128台电脑连接

#define MAXDATASIZE 100

void pthread_recv(void *arg);

void Pthread_send(void * arg);

int main()

{

struct sockaddr_in server_sockaddr,client_sockaddr;

int sockfd,client_fd,sin_size,ret;

pthread_t id1,id2;

sin_size =sizeof(struct sockaddr);

//struct sockaddr_in server_sockaddr,client_sockaddr;

//建立一个socket连接

//目前都是AF_INET(ipv4)；SOCK_STREAM(TCP),如果是UDP,则SOCK_DGRAM

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

perror("socket");

exit(1);

}

printf("socket success!,sockfd=%d\n",sockfd);

//bind用于本地IP地址和端口的绑定

server_sockaddr.sin_family=AF_INET;

server_sockaddr.sin_port=htons(SERVPORT);

server_sockaddr.sin_addr.s_addr=INADDR_ANY;         //htonl(INADDR_ANY)

bzero(&(server_sockaddr.sin_zero),8);

//把本端的信息绑定

if(bind(sockfd,(struct sockaddr *)&server_sockaddr,sizeof(struct sockaddr))==-1)

{

perror("bind");

exit(1);

}

printf("bind success!\n");

if(listen(sockfd,BACKLOG)==-1)

{

perror("listen");

exit(1);

}

printf("listening....\n");

//接受并保存客户端的信息

if((client_fd=accept(sockfd,(struct sockaddr *)&client_sockaddr,&sin_size))==-1)

{

perror("accept");

exit(1);

}

printf("client_fd=%d",client_fd);

pthread_create(&id1,NULL,(void *) pthread_recv,(void*)&client_fd);

if(ret != 0)

perror("pthread_recv creat");

ret=pthread_create(&id2,NULL,(void *)Pthread_send,(void*)&client_fd);

if(ret != 0)

perror("Pthread_send creat");

pthread_join(id1,NULL);

pthread_join(id2,NULL);

close(sockfd);

}

//服务器发送线程

void Pthread_send(void * arg)

{

int buf_len, client_fd,sendbytes;

char buf[MAXDATASIZE];

client_fd = *((int *)arg);

printf("server send: ");

while(1)

{

fgets(buf,MAXDATASIZE,stdin);

buf_len =sizeof(buf);

if((sendbytes = send(client_fd ,buf,buf_len,0))==-1)

{

perror("send");

exit(1);

}

if(!strncmp(buf,"end",3))         //只比较字符串的前三个字符

break;

sleep(2);

}

}

//服务器接收数据线程

void pthread_recv(void *arg)

{

int buf_len, client_fd,recvbytes;

char buf[MAXDATASIZE];

client_fd = *((int *)arg);

//接收服务端发来的信息

while(1)

{

if((recvbytes = recv(client_fd ,buf,MAXDATASIZE,0))==-1)

{

perror("recv");

exit(1);

}

else

{

buf[recvbytes]=0;

printf("server received data from server is :%s\n",buf);

if(!strncmp(buf,"end",3))         //只比较字符串前三个字符

break;

}

sleep(1);

}

}

客户端的代码:

#include <stdio.h>

#include <stdlib.h>

#include <errno.h>

#include <string.h>

#include <netdb.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <sys/socket.h>

#define SERVPORT 3333

#define MAXDATASIZE 100

void pthread_recv(void *arg);

void Pthread_send(void * arg);

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

int sockfd,sin_size,ret;

struct hostent *host;

pthread_t id1,id2;

struct sockaddr_in serv_addr;         //套接字的地址结构

struct sockaddr_in server_sockaddr;

if(argc < 2)

{

fprintf(stderr,"Please enter the server's hostname!\n");

exit(1);

}

//AF_INET:使用的是IPV4

//SOCK_STREAM:流式套接字

if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1)

{

perror("socket");

exit(1);

}

printf("sockfd=%d\n",sockfd);

serv_addr.sin_family=AF_INET;

serv_addr.sin_port=htons(SERVPORT);

//serv_addr.sin_addr=*((struct in_addr *)host->h_addr);

//host->h_addr强制类型转换;建议直接使用下面的方法

serv_addr.sin_addr.s_addr=inet_addr(argv[1]);   //"127.0.0.1");       Internet地址

bzero(&(serv_addr.sin_zero),8);

//连接

if(connect(sockfd,(struct sockaddr *)&serv_addr,sizeof(struct sockaddr))==-1)

{

perror("connect");

exit(1);

}

ret=pthread_create(&id1,NULL,(void *)Pthread_send,(void*)&sockfd);

if(ret != 0)

perror("Pthread_send creat");

pthread_create(&id2,NULL,(void *) pthread_recv,(void*)&sockfd);

if(ret != 0)

perror("pthread_recv creat");

pthread_join(id1,NULL);

pthread_join(id2,NULL);

close(sockfd);

}

//客户端发送数据线程

void Pthread_send(void * arg)

{

int buf_len, sockfd,sendbytes;

char buf[MAXDATASIZE];

sockfd = *((int *)arg);

printf("client send: ");

while(1)

{

fgets(buf,MAXDATASIZE,stdin);

buf_len =sizeof(buf);

if((sendbytes = send(sockfd,buf,buf_len,0))==-1)

{

perror("send");

exit(1);

}

if(!strncmp(buf,"end",3))         //只比较字符串的前三个字符

break;

sleep(2);

}

}

//客户端接收数据线程

void pthread_recv(void *arg)

{

int buf_len, sockfd,recvbytes;

char buf[MAXDATASIZE];

sockfd = *((int *)arg);

//接收服务端发来的信息

while(1)

{

if((recvbytes = recv(sockfd,buf,MAXDATASIZE,0))==-1)

{

perror("recv");

exit(1);

}

else

{

buf[recvbytes]=0;

printf("client received data from server is :%s\n",buf);

if(!strncmp(buf,"end",3))         //只比较字符串的前三个字符

break;

}

sleep(1);

}

}