服务端客户端相互通信的实现，请多线程实现，请给出相应c代码

以下是一个简单的多线程客户端和服务器端通信的示例代码，使用C语言编写。

服务器端代码：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <pthread.h>

#define MAX_CLIENTS 5
#define BUF_SIZE 1024

void *connection_handler(void *);

int main(int argc, char *argv[]) {
    int socket_desc, client_sock, c, *new_sock;
    struct sockaddr_in server, client;
    char *message;

    // 创建套接字
    socket_desc = socket(AF_INET, SOCK_STREAM, 0);
    if (socket_desc == -1) {
        printf("Could not create socket");
    }

    // 准备服务器结构体
    server.sin_family = AF_INET;
    server.sin_addr.s_addr = INADDR_ANY;
    server.sin_port = htons(8888);

    // 绑定套接字
    if (bind(socket_desc, (struct sockaddr *)&server, sizeof(server)) < 0) {
        perror("bind failed. Error");
        return 1;
    }

    // 监听套接字
    listen(socket_desc, MAX_CLIENTS);

    printf("Waiting for incoming connections...\n");
    c = sizeof(struct sockaddr_in);

    while ((client_sock = accept(socket_desc, (struct sockaddr *)&client, (socklen_t *)&c))) {
        printf("Connection accepted from %s:%d\n", inet_ntoa(client.sin_addr), ntohs(client.sin_port));

        // 创建新线程处理连接
        pthread_t sniffer_thread;
        new_sock = malloc(1);
        *new_sock = client_sock;

        if (pthread_create(&sniffer_thread, NULL, connection_handler, (void *)new_sock) < 0) {
            perror("could not create thread");
            return 1;
        }

        printf("Handler assigned\n");
    }

    if (client_sock < 0) {
        perror("accept failed");
        return 1;
    }

    return 0;
}

void *connection_handler(void *socket_desc) {
    int sock = *(int *)socket_desc;
    int read_size;
    char client_message[BUF_SIZE];

    // 接收消息并发送回复
    while ((read_size = recv(sock, client_message, BUF_SIZE, 0)) > 0) {
        printf("Received message: %s\n", client_message);

        if (write(sock, client_message, strlen(client_message)) < 0) {
            perror("write failed");
            return NULL;
        }

        memset(client_message, 0, BUF_SIZE);
    }

    if (read_size == 0) {
        printf("Client disconnected\n");
    } else if (read_size == -1) {
        perror("recv failed");
    }

    free(socket_desc);

    return NULL;
}

客户端代码：

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

#define BUF_SIZE 1024

int main(int argc, char *argv[]) {
    int sock;
    struct sockaddr_in server;
    char message[BUF_SIZE], server_reply[BUF_SIZE];

    // 创建套接字
    sock = socket(AF_INET, SOCK_STREAM, 0);
    if (sock == -1) {
        printf("Could not create socket");
    }

    // 准备服务器结构体
    server.sin_addr.s_addr = inet_addr("127.0.0.1");
    server.sin_family = AF_INET;
    server.sin_port = htons(8888);

    // 连接服务器
    if (connect(sock, (struct sockaddr *)&server, sizeof(server)) < 0) {
        perror("connect failed. Error");
        return 1;
    }

    printf("Connected to server\n");

    // 发送消息并接收回复
    while (1) {
        printf("Enter message: ");
        fgets(message, BUF_SIZE, stdin);

        if (write(sock, message, strlen(message)) < 0) {
            perror("write failed");
            return 1;
        }

        if (read(sock, server_reply, BUF_SIZE) < 0) {
            perror("read failed");
            return 1;
        }

        printf("Server reply: %s\n", server_reply);

        memset(message, 0, BUF_SIZE);
        memset(server_reply, 0, BUF_SIZE);
    }

    close(sock);

    return 0;
}

该示例中，服务器可以同时处理多个客户端连接，每个客户端连接都会创建一个新线程来处理。在客户端，用户可以输入消息并发送给服务器，服务器接收消息并回复相同的消息给客户端。这个示例中仅仅只是简单的演示了客户端和服务器的基本通信流程，可以根据实际需求进行调整和扩展。