Re: Multithreaded winsock

From:

"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>

Newsgroups:

microsoft.public.vc.language

Date:

Tue, 05 Jun 2007 21:20:14 -0400

Message-ID:

<XLCdnZZwV7VJlvvbnZ2dnUVZ_uCinZ2d@comcast.com>

rseedle wrote:

I have a multithreaded winsock application which works most of the time. The
problem I have is that in a wireless environment I can't depend on a good
connect. I have written some code to recover from the socket when the server
disappears and it seems to work. The issue I see is that the recv thread
refuses to let go of processing control when the socket disappears. Thus none
of the other threads can run until the socket becomes accessible again. Any
ideas ?

Randy
...
byte_count = recv(ConnectSocket, (char *)&data_in[0],
NETWORK_IN_BUFFER_LENGTH, 0);

Possible quick fix: The recv call will return if you close the socket
handle from some other thread.

It appears from the code you posted that you are using a blocking
socket. That's a mistake in most Windows programs, especially with the
kind of problem you have. Windows provides non-blocking sockets that
let you stay in control. Study WSAEventSelect or WSAAsyncSelect.

--
Scott McPhillips [MVP VC++]