UDP套接字的WSASend在没有可用目标时触发FD_READ

我正在为UDP套接字类编写C++代码，以处理基本操作（如连接、发送和接收数据）。我尝试将网络事件机制与WSAEventSelect一起用于与套接字相关联的这些基本操作。当我使用WSASend将数据发送到接收数据的（UDP）目的地时，一切都很顺利。但是，当我使用WSASend将数据发送到不存在（UDP）或无法通过网络访问的目的地时，我会触发FD_READ事件。这当然会导致严重的问题，因为没有实际的数据可以接收！！

我无法解释为什么会发生这种事——有什么想法吗
也许我做错了什么，以下是我代码的相关部分：

WSADATA m_wsaData ;         
SOCKET  m_Socket ;          
WSAEVENT    m_SocketEvent ;
if(WSAStartup(MAKEWORD(2,2), &m_wsaData) != 0)
{
// some error
}
// Create a new socket to receive datagrams on
struct addrinfo hints, *res = NULL ;
int rc ;
memset(&hints, 0, sizeof(hints)) ;
hints.ai_family = AF_UNSPEC ;
hints.ai_socktype = SOCK_DGRAM ;
hints.ai_protocol = IPPROTO_UDP ;
rc = getaddrinfo("SomePC", "3030", &hints, &res) ;
if(rc == WSANO_DATA)
{
    // some error
}
if ((m_Socket = WSASocket(res->ai_family, res->ai_socktype, res->ai_protocol, NULL, 0, 0)) == INVALID_SOCKET)
{
    // some error
} 
// create event and associate it with the socket
m_SocketEvent = WSACreateEvent() ;
if(m_SocketEvent == WSA_INVALID_EVENT)
{
    // some error
}
// associate only the following events: close, read, write
if(SOCKET_ERROR == WSAEventSelect(m_Socket, m_SocketEvent, FD_CLOSE+FD_READ+FD_WRITE))
{
    // some error
}
// connect to a server
int ConnectRet = WSAConnect(m_Socket, (SOCKADDR*)res->ai_addr, res->ai_addrlen, NULL, NULL, NULL, NULL) ;
if(ConnectRet == SOCKET_ERROR)
{
    // some error
}

然后，每当我试图通过套接字将一些数据发送到无法侦听或无法访问的（UDP套接字）目的地时，我总是会触发FD_READ：

char buf[32] ;  // some data to send...
WSABUF DataBuf;
DataBuf.len = 32;
DataBuf.buf = (char*)&buf;
DWORD NumBytesActualSent ;
if( SOCKET_ERROR == WSASend(m_Socket, &DataBuf, 1, &NumBytesActualSent,0,0,0))
{
    if(WSAGetLastError() == WSAEWOULDBLOCK) // non-blocking socket - wait for send ok ?
    {
        // handle WSAEWOULDBLOCK...
    }
    else
    {
        // some error
        return ;
    }
}
int ret = WSAWaitForMultipleEvents(1, &m_SocketEvent, FALSE, INFINITE, FALSE) ;

if(ret == WAIT_OBJECT_0)
{
    WSANETWORKEVENTS NetworkEvents ;
    ZeroMemory(&NetworkEvents, sizeof(NetworkEvents)) ;
    if(SOCKET_ERROR == WSAEnumNetworkEvents(m_Socket, m_SocketEvent, &NetworkEvents))
    {
        return ; // some error
    }
    if(NetworkEvents.lNetworkEvents & FD_READ)  // Read ?
    {
        if(NetworkEvents.iErrorCode[FD_READ_BIT] != 0)  // read not ok ?
        {
            // some error
        }
        else
        {
            TRACE("Read Event Triggered ! - Why ? ? ? ? ? ? ?n") ;
        }
    }
}

任何帮助或见解都将不胜感激！谢谢Amit C.