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Date: Sat, 24 Jan 2009 15:30:34 -0500
Message-ID: <7701e1400901241230k43f9f8cbub8740e7f517ab8e4@mail.gmail.com>
Subject: Re: Problem using select() with com0com virtual serial ports
From: Paul Ingemi <pingemi AT gmail DOT com>
To: cygwin AT cygwin DOT com
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* On Thu, Jan 22, 2009 at 10:55:22AM -0500 Christopher Faylor wrote:
> On Thu, Jan 22, 2009 at 10:25:32AM -0500, Paul Ingemi wrote:
[...]
> It is a simple enough hack that I don't mind adding it, if it fixes your
> problem but I am not convinced that your driver is operating correctly.
>
> As I had added serial port access to the Windows version of VICE one or
> two months ago, I can tell that the com0com driver is indeed buggy.
>
> IMHO, the better solution is to fix com0com, and not to apply some
> hotfixes to other software (cygwin, VICE, whatever). That's the approach
> I followed, too, ignoring com0com completely. If I might have some time,
> I might want to debug com0com myself, but don't hold your breath on it.

I agree and adding a hack to cygwin isn't necessary due to the
existance of a workaround. That said, I think it's premature to blame
com0com without finding the root cause of the problem.

Over the past two days I've been attempting to create an -mno-cygwin
executable that can reproduce the behavior I'm seeing under Cygwin.
Thus far I haven't successfully reproduced this behavior outside of a
Cygwin environment despite copying most of the code for how Cygwin
performs select() and read().

Hopefully in the future I'll be able to provide more helpful information.

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