windows c语言 socket编程实例

### 回答1：
以下是一个简单的 Windows 平台下使用 C 语言编写的 socket 编程实例：

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

#define MAX_BUFFER_SIZE 1024

int main()
{
WSADATA wsaData;
SOCKET serverSocket, clientSocket;
struct sockaddr_in serverAddr, clientAddr;
int clientAddrLen = sizeof(clientAddr);
char buffer[MAX_BUFFER_SIZE];
char response[MAX_BUFFER_SIZE] = "Hello from server!";

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

// 创建服务器 socket
serverSocket = socket(AF_INET, SOCK_STREAM, 0);
if (serverSocket == INVALID_SOCKET)
{
printf("Failed to create server socket.\n");
WSACleanup();
return 1;
}

// 设置服务器地址和端口
serverAddr.sin_family = AF_INET;
serverAddr.sin_addr.s_addr = INADDR_ANY;
serverAddr.sin_port = htons(12345);

// 绑定服务器地址和端口到 socket
if (bind(serverSocket, (struct sockaddr*)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR)
{
printf("Failed to bind server address.\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

// 开始监听客户端连接
if (listen(serverSocket, 5) == SOCKET_ERROR)
{
printf("Failed to listen for client connections.\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Server is listening for incoming connections...\n");

// 接受客户端连接并进行通信
while (1)
{
// 等待客户端连接
clientSocket = accept(serverSocket, (struct sockaddr*)&clientAddr, &clientAddrLen);
if (clientSocket == INVALID_SOCKET)
{
printf("Failed to accept client connection.\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Client connected: %s:%d\n", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));

// 接收客户端发送的数据
memset(buffer, 0, sizeof(buffer));
if (recv(clientSocket, buffer, sizeof(buffer), 0) == SOCKET_ERROR)
{
printf("Failed to receive data from client.\n");
closesocket(clientSocket);
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Received data from client: %s\n", buffer);

// 发送响应给客户端
if (send(clientSocket, response, strlen(response), 0) == SOCKET_ERROR)
{
printf("Failed to send response to client.\n");
closesocket(clientSocket);
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Response sent to client: %s\n", response);

// 关闭客户端 socket
closesocket(clientSocket);
}

// 关闭服务器 socket
closesocket(serverSocket);

// 清理 Winsock
WSACleanup();

return 0;
}

在该例子中，服务器创建一个 socket 监听客户端的连接请求。一旦有客户端连接进来，服务器会接收客户端发送的数据，然后返回一个固定的响应给客户端。

### 回答2：
以下是一个使用Windows的C语言编写的简单socket编程实例：

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

#define MAX_BUFFER_SIZE 1024
#define DEFAULT_PORT 8080

int main()
{
    WSADATA wsaData;
    SOCKET listenSocket, clientSocket;
    struct sockaddr_in serverAddr, clientAddr;
    int clientAddrSize;
    char buffer[MAX_BUFFER_SIZE];

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

    // 创建监听socket
    listenSocket = socket(AF_INET, SOCK_STREAM, 0);
    if (listenSocket == INVALID_SOCKET)
    {
        printf("创建socket失败.\n");
        WSACleanup();
        return 1;
    }

    // 设置服务器地址和端口
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_port = htons(DEFAULT_PORT);
    serverAddr.sin_addr.s_addr = INADDR_ANY;

    // 绑定socket到服务器地址和端口
    if (bind(listenSocket, (struct sockaddr *)&serverAddr, sizeof(serverAddr)) == SOCKET_ERROR)
    {
        printf("绑定socket失败.\n");
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

    // 开始监听连接请求
    if (listen(listenSocket, SOMAXCONN) == SOCKET_ERROR)
    {
        printf("监听连接请求失败.\n");
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

    printf("服务器正在监听端口 %d ...\n", DEFAULT_PORT);

    while (1)
    {
        // 接受客户端连接请求
        clientSocket = accept(listenSocket, (struct sockaddr *)&clientAddr, &clientAddrSize);
        if (clientSocket == INVALID_SOCKET)
        {
            printf("接收连接失败.\n");
            closesocket(listenSocket);
            WSACleanup();
            return 1;
        }

        // 从客户端读取数据
        memset(buffer, 0, sizeof(buffer));
        if (recv(clientSocket, buffer, MAX_BUFFER_SIZE, 0) == SOCKET_ERROR)
        {
            printf("接收数据失败.\n");
            closesocket(clientSocket);
            WSACleanup();
            return 1;
        }

        // 打印接收到的数据
        printf("接收到来自客户端的数据: %s\n", buffer);

        // 发送响应给客户端
        const char *response = "服务器已收到你的请求.";
        if (send(clientSocket, response, strlen(response), 0) == SOCKET_ERROR)
        {
            printf("发送响应失败.\n");
            closesocket(clientSocket);
            WSACleanup();
            return 1;
        }

        // 关闭客户端socket
        closesocket(clientSocket);
    }

    // 关闭监听socket
    closesocket(listenSocket);

    // 清理Winsock库
    WSACleanup();

    return 0;
}

这个例子创建了一个服务器程序，它通过在本地8080端口监听连接请求。一旦有客户端连接，服务器将接收该客户端的请求，并向客户端发送一个简单的响应。此例仅用于演示目的，并省略了错误处理和多线程处理。在实际开发中，您还需要根据需求添加适当的错误处理和多线程支持。

### 回答3：
以下是一个简单的Windows C语言socket编程实例：

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

#define MAX_BUFFER_SIZE 1024
#define PORT 8080

int main() {
WSADATA wsaData;
SOCKET serverSocket, clientSocket;
struct sockaddr_in serverAddress, clientAddress;
char buffer[MAX_BUFFER_SIZE];

// 初始化Winsock库
if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
fprintf(stderr, "Failed to initialize Winsock\n");
return 1;
}

// 创建服务器socket
if ((serverSocket = socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) {
fprintf(stderr, "Failed to create server socket\n");
WSACleanup();
return 1;
}

// 绑定服务器地址和端口
serverAddress.sin_family = AF_INET;
serverAddress.sin_addr.s_addr = INADDR_ANY;
serverAddress.sin_port = htons(PORT);

if (bind(serverSocket, (struct sockaddr*)&serverAddress, sizeof(serverAddress)) == SOCKET_ERROR) {
fprintf(stderr, "Failed to bind server socket\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

// 监听客户端连接请求
if (listen(serverSocket, 1) == SOCKET_ERROR) {
fprintf(stderr, "Failed to listen for client connections\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Server is listening on port %d\n", PORT);

// 接受客户端连接
int clientAddressSize = sizeof(clientAddress);
if ((clientSocket = accept(serverSocket, (struct sockaddr*)&clientAddress, &clientAddressSize)) == INVALID_SOCKET) {
fprintf(stderr, "Failed to accept client connection\n");
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Client connected\n");

// 接收和发送数据
while (1) {
memset(buffer, 0, sizeof(buffer));

if (recv(clientSocket, buffer, sizeof(buffer), 0) == SOCKET_ERROR) {
fprintf(stderr, "Failed to receive data from client\n");
closesocket(clientSocket);
closesocket(serverSocket);
WSACleanup();
return 1;
}

printf("Received from client: %s", buffer);

if (send(clientSocket, buffer, strlen(buffer), 0) == SOCKET_ERROR) {
fprintf(stderr, "Failed to send data to client\n");
closesocket(clientSocket);
closesocket(serverSocket);
WSACleanup();
return 1;
}
}

// 关闭socket和Winsock库
closesocket(clientSocket);
closesocket(serverSocket);
WSACleanup();

return 0;
}
以上是一个简单的基于Windows平台的C语言socket编程示例。它创建了一个服务器端socket，并通过指定的端口监听客户端连接请求。一旦有客户端连接成功，服务器将接收来自客户端的数据，并将其发送回客户端。这个过程将持续进行，直到服务器或客户端关闭连接。