UDP发送和接收

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

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

#define RECV_IP "127.0.0.1"
#define RECV_PORT 8899
#define LEN_RECV_BUF 2048

int main()
{
    std::ostringstream ossTemp;
    WSAData wsaData;

    std::cout<<"Start..."<<std::endl;

    WSAStartup(MAKEWORD(2,2),&wsaData);
    SOCKET sktRecv=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);

    sockaddr_in addrRecv;
    addrRecv.sin_family=AF_INET;
    addrRecv.sin_addr.s_addr=inet_addr(RECV_IP);
         //htonl(INADDR_ANY);
    addrRecv.sin_port=htons(RECV_PORT);

    int retVal;

    retVal=bind(sktRecv,(sockaddr*)&addrRecv,sizeof(addrRecv));

    sockaddr_in addrClient;
    char buf[LEN_RECV_BUF];
    int len=sizeof(addrClient);
    while(true)
    {
        memset(buf,0,LEN_RECV_BUF);
        retVal=recvfrom(sktRecv,buf,LEN_RECV_BUF,0,(sockaddr*)&addrClient,&len);
        if(SOCKET_ERROR==retVal)
        {
            ossTemp<<"recvfrom error : "<<retVal<<"\n";
            OutputDebugString(ossTemp.str().c_str());
            break;
        }
        if(strlen(buf)>0)
            std::cout<<buf<<std::endl;
    }

    closesocket(sktRecv);
    WSACleanup();

    std::cout<<"Recv Over"<<std::endl;
    getchar();
    return -1;
}

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

#define IP_SEND "127.0.0.1"
#define PORT_SEND 8899
#define LEN_SEND_BUF 1024

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

int main()
{
    WSAData wsaData;
    WSAStartup(MAKEWORD(2,2),&wsaData);

    std::cout<<"Begin Sending..."<<std::endl;

    std::ostringstream ossTemp;
    SOCKET sktSend=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP);
    sockaddr_in addrSend;
    addrSend.sin_family=AF_INET;
    addrSend.sin_addr.s_addr=inet_addr(IP_SEND);
    addrSend.sin_port=htons(PORT_SEND);
    int retVal;

    char buf[LEN_SEND_BUF];
    int len=sizeof(addrSend);
    int index=0;
    while(true)
    {
        if(index>255)
            break;
        ossTemp.str("");
        ossTemp<<index;
        memset(buf,0,LEN_SEND_BUF);
        memcpy(buf,ossTemp.str().c_str(),sizeof(int));
        retVal=sendto(sktSend,buf,LEN_SEND_BUF,0,(sockaddr*)&addrSend,len);
        if(SOCKET_ERROR==retVal)
        {
            ossTemp.str("");
            ossTemp<<"sendto error : "<<retVal;
            OutputDebugString( ossTemp.str().c_str() );
            break;
        }
        std::cout<<"Send : "<<buf<<std::endl;
        index++;
    }

    closesocket(sktSend);
    WSACleanup();

    std::cout<<"Send Over"<<std::endl;
    getchar();
    return 0;
}