服务器端 客户端 之间socket通信（C实现）

 1.服务器端

#include
#include
#include
#include
#include
#include
#include
#include
#include
#include

#define PORT 2345
#define MAXSIZE 1024

int main(int argc, char *argv[])
{
    int i=1,h=2;

    printf("i + h = %d\n", i+h);

    int sockfd, newsockfd;

    //定义服务端套接口数据结构
    struct sockaddr_in server_addr;
    struct sockaddr_in client_addr;
    int sin_size, portnumber;

    //发送数据缓冲区
    char buf[MAXSIZE];

    //定义客户端套接口数据结构
    int addr_len = sizeof(struct sockaddr_in);

    //创建socket接口
    //协议族 AF_INET：TCP/IP – IPv4
    if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0){
        fprintf(stderr, "create socket failed\n");
        exit(EXIT_FAILURE);
    }

    puts("create socket success");
    printf("socket is %d\n", sockfd);

    //清空表示地址的结构体变量
    bzero(&server_addr, sizeof(struct sockaddr_in));

    //设置addr的成员变量信息
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);

    //设置ip为本机ip
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    //绑定端口
    if(bind(sockfd, (struct sockaddr*)(&server_addr), sizeof(struct sockaddr)) < 0){
        fprintf(stderr, "bind failed\n");
        exit(EXIT_FAILURE);
    }

    puts("bind success\n");

    //监听端口
    if(listen(sockfd, 10) < 0){
        perror("listen fail\n");
        exit(EXIT_FAILURE);
    }

    puts("listen successs\n");
    sin_size = sizeof(struct sockaddr_in);
    printf("sin_size is %d\n", sin_size);

    //接收，等待连接
    if((newsockfd = accept(sockfd, (struct sockaddr *)(&client_addr), &sin_size)) < 0){
        perror("accept error");
        exit(EXIT_FAILURE);
    }

    printf("accept a new connetction\n");
    printf("new socket id is %d\n", newsockfd);
    printf("Accept cilent ip is %s\n", inet_ntoa(client_addr.sin_addr));
    printf("Connect successful please input message\n");

    char mybuf[1024];
    char sendbuf[1024];

    while(1){
        int len = recv(newsockfd, mybuf, sizeof(mybuf), 0);
        
        //strcmp比较字符串
        if(strcmp(mybuf, "exit\n") == 0) break;

        //输出buf中数据
        fputs(mybuf, stdout);

        send(newsockfd, mybuf, len, 0);

        memset(sendbuf, 0, sizeof(sendbuf));
        memset(mybuf, 0, sizeof(mybuf));
    }

    close(newsockfd);
    close(sockfd);
    puts("exit success");
    exit(EXIT_SUCCESS);
    return 0;
}

2.客户端 

#include
#include
#include
#include
#include
#include
#include
#include
#include

#define PORT 2345

int count = 1;

int main()
{
    int sockfd;
    char buffer[2014];
    struct sockaddr_in server_addr;
    struct hostent *host;
    int nbytes;

    //创建socket
    if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1){
        fprintf(stderr, "Socket Error is %s\n", strerror(errno));
        exit(EXIT_FAILURE);
    }

    //清空表示地址的结构体变量
    bzero(&server_addr, sizeof(server_addr));

    //设置addr的成员变量信息
    server_addr.sin_family = AF_INET;
    server_addr.sin_port = htons(PORT);

    //设置ip为本机ip
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);

    //客户端发出请求
    if(connect(sockfd, (struct sockaddr *)(&server_addr), sizeof(struct sockaddr)) == -1){
        fprintf(stderr, "Connect failed\n");
        exit(EXIT_FAILURE);
    }

    char sendbuf[1024];
    char recvbuf[2014];

    while(1){

        // fgets(sendbuf, sizeof(sendbuf), stdin);
        // send(sockfd, sendbuf, strlen(sendbuf), 0);

        // if(strcmp(sendbuf, "exit\n") == 0) break;
        // recv(sockfd, recvbuf, sizeof(recvbuf), 0);
        // fputs(recvbuf, stdout);
        // memset(sendbuf, 0, sizeof(sendbuf));
        // memset(recvbuf, 0, sizeof(recvbuf));


        fgets(sendbuf, sizeof(sendbuf), stdin);
        send(sockfd, sendbuf, strlen(sendbuf), 0);
        //fputs(sendbuf, stdout);


        if(strcmp(sendbuf, "exit\n") == 0) break;
        recv(sockfd, recvbuf, sizeof(recvbuf), 0);
        fputs(recvbuf, stdout);
        memset(sendbuf, 0, sizeof(sendbuf));
        memset(recvbuf, 0, sizeof(recvbuf));

    }

    close(sockfd);
    exit(EXIT_SUCCESS);
    return 0;
}

参考博客：(4条消息) linux网络编程之用socket实现简单客户端和服务端的通信（基于TCP）_kunkliu的博客-CSDN博客