Re: Blocking RECV call & Shutting down Thread

From:
"aDITYA" <aditya.raut@gmail.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
24 Jul 2006 22:52:12 -0700
Message-ID:
<1153806732.587339.132700@i42g2000cwa.googlegroups.com>
Hi Mak,

Just add TimeOut for receiving data &
You can add loop like

while ( ! m_ExitThread )
{
     if(recv(..)==SOCKET_ERROR)
     {
         if(WSAGetLastError()==timeout)
         {
                 if(m_ExitThread)
                      goto end_thread;
         }
         else
         {
                   Socket is closed now.
         }
     :
     :
     :
     }
end_thread:
}

You can choose the time out period as per your req.

- Aditya
mak wrote:

Hi Everyone,

I have a problem with my socket / MFC thread. In my software system, I
have 2 sockets and 2 threads, other than the main application thread.

Sockets:

#1: Command Response Socket
#2: High Speed Socket

Threads:

#1 : Command Response Socket Receive Thread
#2 : High Speed Socket Receive Thread.

The threads look something like this:

DWORD SomeThread (LPVOID pparam)
{

   //note that this is a blocking calll
     while(recv (........) )
    {
               //do some work
     }

    return 0;

}

This works great, other than I cant shut down the thread properly. I
tried making the socket asynchronous and adding a flag in the while
loop like, while (recv(....) & !exit), but that doesnt work out too
well, it chews up a lot of duty cycle.

I tried ioctrlsocket ( s, FIONREAD (or something)) to read how many
bytes if any are available before i read. B ut that too uses up much
duty cycle.

I tried using WSAEVents and WSAEventSelect, and waiting for the
events, but im not sure I got that working properly. It would wait like
it should, and the wait call returned a big number that was not
specified in MSDN.

I hear TerminateThread is bad. BTW, these are CWinThread objects.

Any help or example would be appreciated.

Thanks.

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