Re: Deaf CAsyncSocket on Windows Service.

From:
"Scott McPhillips [MVP]" <org-dot-mvps-at-scottmcp>
Newsgroups:
microsoft.public.platformsdk.networking,microsoft.public.vc.language,microsoft.public.vc.mfc
Date:
Tue, 20 Jan 2009 09:58:16 -0500
Message-ID:
<ew3wM#weJHA.4528@TK2MSFTNGP05.phx.gbl>
"Bill >" <<don't want more spam> wrote in message
news:OmTBgIseJHA.2112@TK2MSFTNGP02.phx.gbl...

Scott,

It'as been a busy day so I haven't been able to test on the target system.
At my desk on a test application, I did remove the loop that calls
Receive() until all the data is removed and it still works. So sure
enough, OnReceive() is being called as needed. I'm not sure where I got
the idea I needed to pull out all the data.

Since my derived socket class calls a callback function in the user
application code and it could do anything including pumping messages, I'd
like to put in something to protect against that in my class. You
mentioned code to guard against reentry into OnReceive(). Are you
suggesting this as a fix or as a check that the problem is occurring? What
should this code do if it catches reentry into the function? Jump out
without doing anything? Call Receive() with a zero byte buffer? Etc.?

Thanks,

Bill


The reentry guard was suggested as a diagnostic aid only. Calling an
unknown callback function is an invitation for the callee to lose your next
OnReceive notification under uncontrollable timing conditions. The sure fix
for avoiding such problems is to PostMessage instead of calling a callback.
Then the message handler can do the data handling or perform the callback.

--
Scott McPhillips [VC++ MVP]

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