Re: Serial communication Threading (Thread is blocking)

the thread is blocked on ReadFile code is like this can i avoid this
blocking behaviour.
CString ReadCharbyChar()
{
        CString FromBoard;
    DWORD dwEventMask;
    DWORD dwSize=0;

    if(!SetCommMask(hCom, EV_RXCHAR)) /* Setting Event Type */
    {
        MessageBox(NULL,"Can not set the event","THREAD",MB_OK);
        return FromBoard;
    }
    if(WaitCommEvent(hCom, &dwEventMask, NULL)) /* Waiting For Event to
Occur */
    {
        if(dwEventMask & EV_RXCHAR)
        {
            char szBuf;
            DWORD dwIncommingReadSize;
            do
            {
                if(ReadFile(hCom, &szBuf, 1, &dwIncommingReadSize, NULL) != 0)
                {
                    if(dwIncommingReadSize > 0)
                    {
                        dwSize += dwIncommingReadSize;
                        FromBoard += szBuf;
                    }
                }
                else
                {
                    CloseComHandle();
                    MessageBox(NULL,"ReadFile Failed","THREAD",MB_OK);
                    unsigned long error = ::GetLastError();
                    break;
                }
                if(szBuf == 'n')
                    break;
            } while(dwIncommingReadSize > 0);
        }
    }
    else
    {
        MessageBox(NULL,"Event never happened","THREAD",MB_OK);
        return FromBoard;
    }
    return FromBoard;
}

and the com port hanle is global so i can close the port after killing
the thread.

Is this right or wrong?