C++ Socket UDP "Hello World!"

这是C++ SOCKET网络程序中的C/S结构之UDP "Hello World !"，共两个控制台工程：

//////////////////////////////////////////////////////////////////////////
// UDPServer.cpp

#include <stdio.h>
#include <WINSOCK2.H>

#pragma comment(lib,"WS2_32.lib")
#define BUF_SIZE    64

int main(void)
{
    WSADATA wsd;
    SOCKET  s;
    int     nRet;

    // 初始化套接字动态库
    if(WSAStartup(MAKEWORD(2,2),&wsd) != 0)
    {
        printf("WSAStartup failed !/n");
        return 1;
    }

    // 创建套接字
    s = socket(AF_INET,SOCK_DGRAM,0);
    if(s == INVALID_SOCKET)
    {
        printf("socket() failed ,Error Code:%d/n",WSAGetLastError());
        WSACleanup();
        return 1;
    }

    SOCKET      socketSrv = socket(AF_INET,SOCK_DGRAM,0);
    SOCKADDR_IN addrSrv;
    SOCKADDR_IN addrClient;
    char        buf[BUF_SIZE];
    int         len = sizeof(SOCKADDR);

    // 设置服务器地址
    ZeroMemory(buf,BUF_SIZE);
    addrSrv.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
    addrSrv.sin_family = AF_INET;
    addrSrv.sin_port = htons(5000);

    // 绑定套接字
    nRet = bind(socketSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));
    if(SOCKET_ERROR == nRet)
    {
        printf("bind failed !/n");
        closesocket(s);
        WSACleanup();
        return -1;
    }

    // 从客户端接收数据
    nRet = recvfrom(socketSrv,buf,BUF_SIZE,0,(SOCKADDR*)&addrClient,&len);
    if(SOCKET_ERROR == nRet)
    {
        printf("recvfrom failed !/n");
        closesocket(s);
        WSACleanup();
        return -1;
    }
    // 打印来自客户端发送来的数据
    printf("Recv From Client:%s/n",buf);

    // 向客户端发送数据
    sendto(socketSrv,"UDP Hello World !",sizeof("UDP Hello World !"),0,(SOCKADDR*)&addrClient,len);
    closesocket(s);
    WSACleanup();
    return 0;
}

//////////////////////////////////////////////////////////////////////////
// UDPClient.cpp

#include <stdio.h>
#include <WINSOCK2.H>

#pragma comment(lib,"WS2_32.lib")
#define BUF_SIZE    64

int main(void)
{
    WSADATA wsd;
    SOCKET  s;

    // 初始化套接字动态库
    if(WSAStartup(MAKEWORD(2,2),&wsd) != 0)
    {
        printf("WSAStartup failed !/n");
        return 1;
    }

    // 创建套接字
    s = socket(AF_INET,SOCK_DGRAM,0);
    if(s == INVALID_SOCKET)
    {
        printf("socket() failed, Error Code:%d/n",WSAGetLastError());
        WSACleanup();
        return 1;
    }

    char        buf[BUF_SIZE];  // 接受数据
    SOCKADDR_IN servAddr;       // 服务器套接字地址
    SOCKET      sockClient = socket(AF_INET,SOCK_DGRAM,0);
    int         nRet;

    ZeroMemory(buf,BUF_SIZE);
    strcpy(buf,"UDP Hello World !");

    // 设置服务器地址
    servAddr.sin_family = AF_INET;
    servAddr.sin_addr.S_un.S_addr = inet_addr("192.168.1.254");
    servAddr.sin_port = htons(5000);

    // 向服务器发送数据
    int nServAddLen = sizeof(servAddr);
    if(sendto(sockClient,buf,BUF_SIZE,0,(sockaddr *)&servAddr,nServAddLen) == SOCKET_ERROR)
    {
        printf("recvfrom() failed:%d/n",WSAGetLastError());
        closesocket(s);
        WSACleanup();
        return 1;
    }
    nRet = recvfrom(sockClient,buf,BUF_SIZE,0,(sockaddr *)&servAddr,&nServAddLen);
    if(SOCKET_ERROR == nRet)
    {
        printf("recvfrom failed !/n");
        closesocket(s);
        WSACleanup();
        return -1;
    }

    // 打印来自服务端发送来的数据
    printf("Recv From Server:%s/n",buf);
    closesocket(s);
    WSACleanup();
    return 0;
}

程序运行效果：

源代码下载地址：

http://www.rayfile.com/files/733c832e-a2d8-11de-a838-0014221b798a/

http://blog.csdn.net/wangningyu/article/details/4560835