利用TCP实现套接字通信

一、服务端代码：
server.c

/******** 头文件 *********/

#include <unistd.h>

#include <sys/socket.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <strings.h>

#include <stdlib.h>

#include <stdio.h>

/******** 宏定义 ********/

#define BUFFSIZE 100

int main()

{

    int listenFd, connectFd;

    socklen_t len;

    int n;

    struct sockaddr_in srcAddr, cliAddr;

    char buf[BUFFSIZE];

    //create socket

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

    {

        perror("socket error");

        exit(1);

    }

 

    bzero(&srcAddr, sizeof(srcAddr));

    srcAddr.sin_family = AF_INET;

    srcAddr.sin_port = htons(8888);

    srcAddr.sin_addr.s_addr = htonl(INADDR_ANY);

    //绑定套接字

    if(bind(listenFd, (struct sockaddr*)&srcAddr, sizeof(srcAddr)) == -1)

    {

        perror("bind error");

        exit(1);

    }

    //监听套接字

    if(listen(listenFd, 5) == -1)

    {

        perror("listen error");

        exit(1);

    }

    len = sizeof(cliAddr);

    printf("listening ...\n");

    while(1)

    {

        //从已完成队列中抓取一个套接字进行服务

        if((connectFd = accept(listenFd, (struct sockaddr*)&cliAddr, &len)) == -1)

        {

            perror("accept error");

            exit(1);

        }

        printf("accepted successful\n");

        //从套接字中读取从客户端发来的数据

        while((n = read(connectFd, buf, BUFFSIZE)) > 0)

        {

            if(buf[n] != '\0')

            {

                buf[n] = '\0';

            }

            printf("receive a message: %s", buf);

 

            //将读取的数据写进套接字，发给客户端

            if(write(connectFd, buf, n) < 0)

            {

                perror("write error");

                exit(1);

            }

        }

    }

    //进程退出后，所有打开的文件描述符都会被关闭，因此打开的套接字文件也被关闭

    return 0;

}

二、客户端代码
client.c

/******** 头文件 *********/

#include <unistd.h>

#include <sys/socket.h>

#include <sys/types.h>

#include <netinet/in.h>

#include <stdio.h>

#include <strings.h>

#include <arpa/inet.h>

#include <stdlib.h>

#include <string.h>

/******** 宏定义 *********/

#define BUFFSIZE 100

int main()

{

    int sockFd;

    int n;

    struct sockaddr_in serverAddr;

    char sendBuf[BUFFSIZE], recvBuf[BUFFSIZE];

    //创建套接字

    if((sockFd = socket(AF_INET, SOCK_STREAM, 0)) < 0)

    {

        perror("socket error");

        exit(1);

    }

    bzero(&serverAddr, sizeof(serverAddr));

    serverAddr.sin_family = AF_INET;

    serverAddr.sin_port = htons(8888);

    inet_pton(AF_INET, "127.0.0.1", &serverAddr.sin_addr);

    //连接套接字

    if(connect(sockFd, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) < 0)

    {

        perror("connect error");

        exit(1);

    }

    //从标准输入中读取一行数据

    while(fgets(sendBuf, BUFFSIZE, stdin) != NULL)

    {

        //将数据写入到套接字，发送给服务器

        write(sockFd, sendBuf, strlen(sendBuf));

 

        //从套接字中读取从服务器发来的数据

        n = read(sockFd, recvBuf, BUFFSIZE);

 

        //将接受到的数据写到标准输出中

        write(STDIN_FILENO, recvBuf, n);

    }

    return 0;

}
三、实验截图
服务端：

客户端：