TCPIP网络编程（尹圣雨）UDP 轮流收发消息(windows)

端口号写的是 2345

客户端

#include <iostream>
#include <winsock2.h>
#pragma comment(lib, "ws2_32.lib")

using std::cout;
using std::endl;
using std::cin;

int main()
{
    WSADATA wsa;

    if (WSAStartup(MAKEWORD(2, 2), &wsa) != 0)
    {
        cout << "startup error" << endl;
    }

    sockaddr_in sd;
    sd.sin_port = htons(2345);
    sd.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
    sd.sin_family = AF_INET;

    SOCKET sock = socket(PF_INET, SOCK_DGRAM, 0);

    // connect(sock, (sockaddr *)&sd, sizeof(sd));
    for (int i = 0; i < 10; ++i)
    {
        char buf[1024];
        cout << "请输入文本:" << endl;
        cin >> buf;
        int len = sizeof(sd);
        sendto(sock, buf, strlen(buf), 0, (sockaddr *)&sd, sizeof(sd));
        len = sizeof(sd);
        memset(&buf, 0, 1024);
        recvfrom(sock, buf, 1024, 0,(sockaddr *)&sd, &len);
        cout << "收到的数据:" << buf<<endl;
    }
    getchar();
    closesocket(sock);
    WSACleanup();
    return 0;
}

服务端

#include <iostream>
#include <WinSock2.h>

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

using std::cout;
using std::endl;
using std::cin;

int main()
{
    WSADATA wsa;
    if (WSAStartup(MAKEWORD(2, 2), &wsa) != 0)
    {
        cout << "WSA Error" << endl;
        return 0;
    }
    sockaddr_in sd;
    sd.sin_family = AF_INET;
    sd.sin_port = htons(2345);
    sd.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");

    SOCKET sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (sock == INVALID_SOCKET)
    {
        cout << "socket error" << endl;
        return 0;
    }
    if (bind(sock, (sockaddr *)&sd, sizeof(sd)) == SOCKET_ERROR)
    {
        cout << "bind error" << endl;
        return 0;
    }
    sockaddr_in clientSd;

    for (int i = 0; i < 10; ++i)
    {
        char buf[1024] = "";
        int len = sizeof(clientSd);
         recvfrom(sock, buf, 1024, 0, (sockaddr *)&clientSd, &len);

        cout << buf<<endl;
        memset(&buf, 0, 1024);
        cout << "请输入数据:" << endl;
        cin >> buf;
        sendto(
            sock, buf, strlen(buf), 0, (sockaddr *)(&clientSd),
        sizeof(clientSd));
    }

    closesocket(sock);
    WSACleanup();
    return 0;
}