#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <string.h>

int main() {
    int server_socket, client_socket;
    struct sockaddr_in server_addr, client_addr;
    char buffer[1024];

    // 创建套接字
    server_socket = socket(AF_INET, SOCK_STREAM, 0);

    // 初始化服务器地址结构体
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    server_addr.sin_port = htons(9999);

    // 绑定套接字到端口
    bind(server_socket, (struct sockaddr*)&server_addr, sizeof(server_addr));

    // 监听连接请求
    listen(server_socket, 5);

    printf("等待客户端连接...\n");

    // 接受连接请求
    socklen_t client_addr_len = sizeof(client_addr);
    client_socket = accept(server_socket, (struct sockaddr*)&client_addr, &client_addr_len);

    printf("客户端 %s:%d 已连接\n", inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));

    while (1) {
        // 接收客户端消息
        memset(buffer, 0, sizeof(buffer));
        recv(client_socket, buffer, sizeof(buffer), 0);
        printf("接收到客户端消息：%s\n", buffer);

        // 发送回复消息
        memset(buffer, 0, sizeof(buffer));
        printf("请输入回复消息：");
        fgets(buffer, sizeof(buffer), stdin);
        send(client_socket, buffer, strlen(buffer), 0);

        // 判断是否退出
        if (strcmp(buffer, "exit\n") == 0) {
            break;
        }
    }

    // 关闭套接字
    close(client_socket);
    close(server_socket);

    return 0;
}

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <string.h>

int main() {
    int client_socket;
    struct sockaddr_in server_addr;
    char buffer[1024];

    // 创建套接字
    client_socket = socket(AF_INET, SOCK_STREAM, 0);

    // 初始化服务器地址结构体
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    server_addr.sin_port = htons(9999);

    // 连接服务器
    connect(client_socket, (struct sockaddr*)&server_addr, sizeof(server_addr));

    while (1) {
        // 发送消息
        memset(buffer, 0, sizeof(buffer));
        printf("请输入消息：");
        fgets(buffer, sizeof(buffer), stdin);
        send(client_socket, buffer, strlen(buffer), 0);

        // 接收回复消息
        memset(buffer, 0, sizeof(buffer));
        recv(client_socket, buffer, sizeof(buffer), 0);
        printf("接收到回复消息：%s\n", buffer);

        // 判断是否退出
        if (strcmp(buffer, "exit\n") == 0) {
            break;
        }
    }

    // 关闭套接字
    close(client_socket);

    return 0;
}