一、用Winsock的API套接字函数实现如下功能：服务器端接收客户端的连接，并向客户端发送“hello ，I am server !”.客户端显示接收到的内容。当一个客户端连接到服务器端后，在服务器端显示该客户端的IP地址。(25分)

以下是用 Winsock 的 API 套接字函数实现的服务器端代码：

#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>

#pragma comment(lib,"ws2_32.lib") // 链接 ws2_32.lib 库

int main()
{
    WSADATA wsaData;
    SOCKET serverSocket, clientSocket;
    struct sockaddr_in serverAddr, clientAddr;
    int clientAddrLen = sizeof(clientAddr);
    char sendBuf[] = "hello, I am server!";
    char recvBuf[1024];

    // 初始化 Winsock
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
        printf("WSAStartup failed!\n");
        return 1;
    }

    // 创建服务器端套接字
    serverSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (serverSocket == INVALID_SOCKET) {
        printf("Failed to create server socket!\n");
        return 1;
    }

    // 绑定服务器端套接字
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(8888);
    serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    if (bind(serverSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {
        printf("Failed to bind server socket!\n");
        closesocket(serverSocket);
        return 1;
    }

    // 监听客户端连接
    if (listen(serverSocket, SOMAXCONN) == SOCKET_ERROR) {
        printf("Failed to listen server socket!\n");
        closesocket(serverSocket);
        return 1;
    }

    // 接收客户端连接并发送欢迎消息
    printf("Waiting for client...\n");
    clientSocket = accept(serverSocket, (struct sockaddr *)&clientAddr, &clientAddrLen);
    if (clientSocket == INVALID_SOCKET) {
        printf("Failed to accept client socket!\n");
        closesocket(serverSocket);
        return 1;
    }
    printf("Client %s connected!\n", inet_ntoa(clientAddr.sin_addr));
    send(clientSocket, sendBuf, sizeof(sendBuf), 0);

    // 接收客户端的消息
    printf("Waiting for message...\n");
    int recvLen = recv(clientSocket, recvBuf, sizeof(recvBuf), 0);
    if (recvLen > 0) {
        recvBuf[recvLen] = '\0';
        printf("Received message from client: %s\n", recvBuf);
    }

    // 关闭套接字并清理 Winsock
    closesocket(clientSocket);
    closesocket(serverSocket);
    WSACleanup();

    return 0;
}

以下是用 Winsock 的 API 套接字函数实现的客户端代码：

#include <stdio.h>
#include <stdlib.h>
#include <winsock2.h>

#pragma comment(lib,"ws2_32.lib") // 链接 ws2_32.lib 库

int main()
{
    WSADATA wsaData;
    SOCKET clientSocket;
    struct sockaddr_in serverAddr;
    char sendBuf[] = "Hello, server!";
    char recvBuf[1024];

    // 初始化 Winsock
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
        printf("WSAStartup failed!\n");
        return 1;
    }

    // 创建客户端套接字
    clientSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (clientSocket == INVALID_SOCKET) {
        printf("Failed to create client socket!\n");
        return 1;
    }

    // 连接服务器端
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(8888);
    serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
    if (connect(clientSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR) {
        printf("Failed to connect to server!\n");
        closesocket(clientSocket);
        return 1;
    }

    // 接收服务器端的消息
    printf("Waiting for message...\n");
    int recvLen = recv(clientSocket, recvBuf, sizeof(recvBuf), 0);
    if (recvLen > 0) {
        recvBuf[recvLen] = '\0';
        printf("Received message from server: %s\n", recvBuf);
    }

    // 发送消息给服务器端
    send(clientSocket, sendBuf, sizeof(sendBuf), 0);

    // 关闭套接字并清理 Winsock
    closesocket(clientSocket);
    WSACleanup();

    return 0;
}