使用winsock+UDP写的一个简单接收端程序（转）

本程序使用VS2008编写，代码如下：

 

//先打开服务器端，服务器在执行完recvfrom()后堵塞，等待接收数据...
#include <winsock2.h>
#include <stdio.h>
#pragma comment(lib,"WS2_32.LIB")
void main()
{
    WSADATA         wsaData;
    SOCKET          ReceivingSocket;
    SOCKADDR_IN     ReceiverAddr;
    int             Port = 8060;
    char            ReceiveBuf[1024] = {0};
    int             BufLength = 1024;
    SOCKADDR_IN     SenderAddr;
    int             SenderAddrSize = sizeof(SenderAddr);
    int             Ret;
    //初始化Winsock 2.2版本
    if((Ret = WSAStartup(MAKEWORD(2,2),&wsaData)) !=0)
    {
        printf("ERROR:WSAStartup failed with %d/n",Ret);
        return;
    }
    //创建一个新的套接字来接收数据报
    if((ReceivingSocket = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP)) == INVALID_SOCKET)
    {
        printf("ERROR:SOCKET failed with %d/n",WSAGetLastError());
        WSACleanup();
        return;
    }
    //建立一个SOCKDDR_IN结构，这个结构将告知bind我们想要使用5150端口接收来自
    //所有接口的数据报
    ReceiverAddr.sin_family = AF_INET;
    ReceiverAddr.sin_port = htons(Port);
    ReceiverAddr.sin_addr.s_addr = htonl(INADDR_ANY);
    //使用bind将这个地址信息和套接字关联起来
    if((bind(ReceivingSocket,(SOCKADDR*)&ReceiverAddr,sizeof(ReceiverAddr))) == SOCKET_ERROR)
    {
        printf("ERROR:bind failed with %d/n",WSAGetLastError());
        closesocket(ReceivingSocket);
        WSACleanup();
        return;
    }
    ////先打开服务器端，服务器在执行完recvfrom()后堵塞，等待接收数据...
    printf("wait to receive data.../n");
    if((Ret = recvfrom(ReceivingSocket,ReceiveBuf,BufLength,0,(SOCKADDR *)&SenderAddr,&SenderAddrSize))
        == SOCKET_ERROR)
    {
      printf("ERROR: recvfrom failed with error %d/n", WSAGetLastError());
      closesocket(ReceivingSocket);
      WSACleanup();
      return;
    }
    printf("We successfully received %d bytes from address %s:%d./n", Ret,
        inet_ntoa(SenderAddr.sin_addr), ntohs(SenderAddr.sin_port));
    for(int id=0; id<5 ; ++id)
        printf("%c",ReceiveBuf[id]);
    //应用程序结束接收数据报后，关闭套接字
    closesocket(ReceivingSocket);
    //应用程序结束后，调用WSACleanup
    WSACleanup();
}