Re: Please Help!!! - CAsyncSocket::OnReceive Not Working for Microsoft UDP Application (msocudp)

On May 20, 12:31 pm, "Scott McPhillips [MVP]" <org-dot-mvps-at-
scottmcp> wrote:


r


Scott,

I have created a CWinThread derived class. I have been trying to
follow some examples from the web.
I am trying to pass the socket from my dialog class to my thread
class. One problem I am having now when running the code is that it is
failing when I am attaching the socket handle to the socket object in
the InitInstance() function of my thread class.
The error I'm getting is access violation. Others seemed to have
gotten this error before. How do you fix this?

Code Snippets:

CProdTestUdpThread (My CWinThread derived class)

BOOL CProdTestUdpThread::InitInstance()
{
    // TODO: perform and per-thread initialization here
    m_UDPSocket.Attach(m_hSocket); (*** THIS IS WHERE THE ERROR
IS OCCURRING ***)

    m_UDPSocket.m_nBytesSent = 0;
    m_UDPSocket.m_sendBuffer = m_sendString;
    m_UDPSocket.m_nBytesBufferSize = m_sendString.GetLength() + 1;

    m_UDPSocket.DoAsyncSendBuff();

    Sleep(m_delay);

    WaitForSingleObject(m_hRcvEvent, INFINITE);

    m_UDPSocket.Detach();

    return TRUE;
}

----------------------------------------------------------------------------=
----------------------------------------
CProdTestDlg (Normal Function definition in my dialog source file --
WHERE I START THE THREAD)

void CProdTestDlg::NormalFunction(int hexNum)
{
    CString sendString, verString = "01", seqString, twoByteHexAddInfo;
    m_cmdString = "02";

    twoByteHexAddInfo.Format("%04x", hexNum);
    seqString.Format("%02x", m_pUDPSocket->m_sequenceNumber);
    sendString = verString + seqString + m_cmdString + twoByteHexAddInfo;

    CProdTestUdpThread *pThread =
        (CProdTestUdpThread *) AfxBeginThread(
        RUNTIME_CLASS(CProdTestUdpThread),
                                THREAD_PRIORITY_HIGHEST,
                                0,
        CREATE_SUSPENDED);

    // Pass the socket to the thread by passing the socket handle.
    // You cannot pass a CSocket object across threads.
    pThread->m_hSocket = m_pUDPSocket->Detach();
    pThread->m_sendString = sendString;
    pThread->m_delay = 10;
    m_pUDPSocket->m_pRcvEvent = &(pThread->m_hRcvEvent);

                // Now start the thread.
                pThread->ResumeThread();

    WaitForSingleObject(pThread->m_hThread, INFINITE);
}

----------------------------------------------------------------------------=
----------------------------------------
MICROSOFT's UDP OnReceive() Function (Instead of the class being
named, CUdpAsySk, I changed it to CProdTestUdpSk).

void CProdTestUdpSk::OnReceive(int nErrorCode)
{
                 ...

    SetEvent(*m_pRcvEvent); // *** NOTIFY THREAD CLASS WHEN ALL 10
                                                            // PACKETS
ARE RECEIVED ***

                 ...
}