Re: Blocking RECV call & Shutting down Thread

From:
"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>
Newsgroups:
microsoft.public.vc.mfc
Date:
Sun, 25 Jun 2006 19:59:59 -0400
Message-ID:
<eV9UfOLmGHA.4808@TK2MSFTNGP05.phx.gbl>
zaki.barak@gmail.com wrote:

Scott McPhillips [MVP] wrote:

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.

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.


You need some checks on the value returned by recv. With that in place
I think you can get your thread shut down by closing the socket handle
from the main thread, then detecting the resulting socket error in the
worker thread.


Scott,

I dont think thats the problem. The problem is that when there is not
data coming on the socket, then RECV is blocked forever. I can not
interrupt the RECV that is blocked forever, and therefore can not shut
down the thread.


The recv is not blocked forever. It will return if the socket is
closed. Close the socket from the main thread.

--
Scott McPhillips [VC++ MVP]

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