windows c socket收发数据

在 Windows 平台上使用 C 语言进行 Socket 编程，可以使用 Winsock 库来实现。下面是一个简单的例子，演示如何在客户端和服务器端之间收发数据：

客户端代码：

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

#pragma comment(lib, "ws2_32.lib")

int main()
{
    WSADATA wsaData;
    SOCKET sock;
    struct sockaddr_in serverAddr;
    char sendBuf[1024];
    char recvBuf[1024];
    int iRet;

    // 初始化 Winsock 库
    iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (iRet != 0) {
        printf("WSAStartup failed with error: %d\n", iRet);
        return 1;
    }

    // 创建套接字
    sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (sock == INVALID_SOCKET) {
        printf("socket failed with error: %d\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_addr.s_addr = inet_addr("127.0.0.1");
    serverAddr.sin_port = htons(8888);

    // 连接服务器
    iRet = connect(sock, (struct sockaddr *)&serverAddr, sizeof(serverAddr));
    if (iRet != 0) {
        printf("connect failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 发送数据
    sprintf(sendBuf, "hello server");
    iRet = send(sock, sendBuf, strlen(sendBuf), 0);
    if (iRet == SOCKET_ERROR) {
        printf("send failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 接收数据
    iRet = recv(sock, recvBuf, 1024, 0);
    if (iRet == SOCKET_ERROR) {
        printf("recv failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 处理接收到的数据
    recvBuf[iRet] = '\0';
    printf("recv: %s\n", recvBuf);

    // 关闭套接字和 Winsock 库
    closesocket(sock);
    WSACleanup();

    return 0;
}

服务器端代码：

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

#pragma comment(lib, "ws2_32.lib")

int main()
{
    WSADATA wsaData;
    SOCKET sock;
    SOCKET clientSock;
    struct sockaddr_in serverAddr;
    struct sockaddr_in clientAddr;
    char recvBuf[1024];
    int iRet;
    int addrLen = sizeof(clientAddr);

    // 初始化 Winsock 库
    iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (iRet != 0) {
        printf("WSAStartup failed with error: %d\n", iRet);
        return 1;
    }

    // 创建套接字
    sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if (sock == INVALID_SOCKET) {
        printf("socket failed with error: %d\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    // 设置服务器地址
    serverAddr.sin_family = AF_INET;
    serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    serverAddr.sin_port = htons(8888);

    // 绑定套接字
    iRet = bind(sock, (struct sockaddr *)&serverAddr, sizeof(serverAddr));
    if (iRet == SOCKET_ERROR) {
        printf("bind failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 监听端口
    iRet = listen(sock, SOMAXCONN);
    if (iRet == SOCKET_ERROR) {
        printf("listen failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    printf("waiting for client...\n");

    // 接受连接
    clientSock = accept(sock, (struct sockaddr *)&clientAddr, &addrLen);
    if (clientSock == INVALID_SOCKET) {
        printf("accept failed with error: %d\n", WSAGetLastError());
        closesocket(sock);
        WSACleanup();
        return 1;
    }

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

    // 接收数据
    iRet = recv(clientSock, recvBuf, 1024, 0);
    if (iRet == SOCKET_ERROR) {
        printf("recv failed with error: %d\n", WSAGetLastError());
        closesocket(clientSock);
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 处理接收到的数据
    recvBuf[iRet] = '\0';
    printf("recv: %s\n", recvBuf);

    // 发送数据
    sprintf(recvBuf, "hello client");
    iRet = send(clientSock, recvBuf, strlen(recvBuf), 0);
    if (iRet == SOCKET_ERROR) {
        printf("send failed with error: %d\n", WSAGetLastError());
        closesocket(clientSock);
        closesocket(sock);
        WSACleanup();
        return 1;
    }

    // 关闭套接字和 Winsock 库
    closesocket(clientSock);
    closesocket(sock);
    WSACleanup();

    return 0;
}