Linux C/S socket通信

server

#include <sys/types.h>//socket
#include <sys/socket.h>//socket,bind,listen,accept,connect
#include <unistd.h>
#include <iostream>
using namespace std;

#include <arpa/inet.h>//itons,inet_aton
#include <netinet/in.h>//inet_aton
#include <cstring>//bzero

#define PORT 6666
int main()
{
    char buf[BUFSIZ];
    struct sockaddr_in serveraddr;
    struct sockaddr_in clientaddr;
    int listenfd,connectfd;
    socklen_t addrlen;//accept中最后一个参数
    int ret,n;
    char clientip[20];

    listenfd = socket(AF_INET,SOCK_STREAM,0);
    if(listenfd==-1)
    {
        perror("socket");
        exit(1);
    }

//端口复用  
    int on = 1;
    if(setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(int))<0)
    {
        perror("setsockopt");
        exit(1);
    }
    
    bzero(&serveraddr,sizeof(serveraddr));
    serveraddr.sin_family = AF_INET;
    serveraddr.sin_port = htons(PORT);
    serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
//  inet_pton(AF_INET,"127,0,0,1",&serveraddr.sin_addr.saddr);  

    ret = bind(listenfd,(struct sockaddr*)&serveraddr,sizeof(serveraddr));
    if(ret == -1)
    {
        perror("bind");
        exit(1);
    }

    ret = listen(listenfd,128);
    if(ret == -1)
    {
        perror("listen");
        exit(1);
        
    }
    else
    {
        cout << "等待连接····"<<endl;
    }

    addrlen = sizeof(clientaddr);
    connectfd = accept(listenfd,(struct sockaddr*)&clientaddr,&addrlen);
    if(connectfd == -1)
    {
        perror("accept");
        exit(1);
    }
    else
    {
        cout << "client have connected" <<endl;
    }
    
    inet_ntop(AF_INET,&clientaddr.sin_addr.s_addr,clientip,sizeof(clientip));
    cout << "clinet ip: "<< (char *)clientip << endl;
    cout << "clinet port: "<< ntohs(clientaddr.sin_port)<<endl;;
/****数据传输*********/
    
    while(1)
    {
        n = read(connectfd,buf,sizeof(buf));
        if(n == 0)//n返回值为0表示读取结束,即客户端关闭
        {
            cout << "client closed"<<endl;
            break;//跳出循环
        }
        
        cout << buf << endl;
        write(connectfd,buf,sizeof(buf));       
        
        bzero(buf,sizeof(buf));
    }

/****************/
    close(listenfd);
    close(connectfd);

    return 0;
}

client

#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include <iostream>
using namespace std;

#include <cstring>
#include <netinet/in.h>//inet_aton
#include <arpa/inet.h>//itons,inet_aton
#define PORT 6666
#define BUFSIZE 1024

int main()
{
    int fd;
    struct sockaddr_in serveraddr;
    fd = socket(AF_INET,SOCK_STREAM,0);
        
    char sndbuf[BUFSIZE];
    char rcvbuf[BUFSIZE];

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

    inet_pton(AF_INET,"127,0,0,1",&serveraddr.sin_addr);    
    if(connect(fd,(struct sockaddr*)&serveraddr,sizeof(serveraddr))==-1)
    {
        perror("connect");
        exit(1);
    }
    else    
    {
        cout<< "server have connected"<<endl;
    }
    
/*************/

    while(cin >> sndbuf)
    {
        
        write(fd,sndbuf,sizeof(sndbuf));
        
        read(fd,rcvbuf,sizeof(rcvbuf));
        cout << "服务器:recieved "<<rcvbuf << endl;

        bzero(sndbuf,sizeof(sndbuf));
        bzero(rcvbuf,sizeof(rcvbuf));
        
    }

/*************/
    close(fd);
    return 0;
}