socket网络通信（udp)

 客户端：

#include <iostream>
#include <stdio.h>
#include <windows.h>
#include <string.h>

using namespace std;

#pragma comment(lib, "WS2_32.lib")


class CInitSock
{
public:
    CInitSock(int version01 = 2, int versiont02 = 2)
    {
        WORD sockVersion = MAKEWORD(2, 2);
        WSADATA wsaData = {0};

        if (WSAStartup(sockVersion, &wsaData) != 0)
        {
            cout << "initlization failed!" << endl;

            exit(0);
        }

    }

    ~CInitSock()
    {
        WSACleanup();
    }
};

CInitSock mysock;


int const MAX_SIZE = 1024;

int main()
{
    char buffer[MAX_SIZE] = "/0";
    sockaddr_in addr = {0};
    int nLen  = sizeof(sockaddr_in);
    SOCKET s;

    addr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
    addr.sin_family = AF_INET;
    addr.sin_port  = htons(4567);
    s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);

    while (true)
    {
        cout << "Please input send data: " << endl;
        cin >> buffer;

        if ((strcmp(buffer, "quit") == 0) || (strcmp(buffer, "exit")) == 0)
        {
            cout << "process exit...." << endl;

            break;
        }

        sendto(s, buffer, strlen(buffer), 0, (sockaddr*)&addr, sizeof(addr));
    }
}

服务器端：

#include <iostream>
#include <stdio.h>
#include <windows.h>

using namespace std;

#pragma comment(lib, "WS2_32.lib")


class CInitSock
{
public:
    CInitSock(int version01 = 2, int versiont02 = 2)
    {
        WORD sockVersion = MAKEWORD(2, 2);
        WSADATA wsaData = {0};

        if (WSAStartup(sockVersion, &wsaData) != 0)
        {
            cout << "initlization failed!" << endl;

            exit(0);
        }

    }

    ~CInitSock()
    {
        WSACleanup();
    }
};

CInitSock mysock;

int main()
{
    SOCKET  s = 0;
    sockaddr_in sin = {0};

    sin.sin_family = AF_INET;
    sin.sin_port = htons(4567);
    sin.sin_addr.S_un.S_addr = INADDR_ANY;

    s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);

    if (bind(s, (LPSOCKADDR)&sin, sizeof(sin)) == SOCKET_ERROR)
    {
        cout << "bind failed!" << endl;

        return 0;
    }

    char  buffer[1024] = "/0";
    sockaddr_in addr  = {0};
    int  nLen  = 0;

    nLen = sizeof(sockaddr_in);

    cout << "------- now service start -------------" << endl;

    while (true)
    {
        int nRecv = 0;

        cout << "wait to receive data............" << endl;

        nRecv = recvfrom(s, buffer, 1024, 0, (sockaddr*)&addr, &nLen);

        if (nRecv > 0)
        {
            buffer[nRecv] = '/0';

            cout << "receve buffer: " << buffer << endl;
        }
    }

    closesocket(s);
}