Message-ID: <17393e3e0812191135v64035dfq1e8f25c2a352872@mail.gmail.com>
Date: Fri, 19 Dec 2008 14:35:09 -0500
From: "Matt Wozniski" <godlygeek@gmail.com>
To: cygwin@cygwin.com
Subject: Re: printf goes to serial port?
In-Reply-To: <E464473DC145404FBD632475DDAF55C6@DFW5RB41>
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On Fri, Dec 19, 2008 at 2:30 PM, Gary R. Van Sickle wrote:
>> From: Alex Martin
>>
>> Hello,
>>
>> I have a cygwin environment, running some software I am
>> writing to talk to some serial devices.
>>
>> Somehow, trying to debug why I could not see printf output to
>> console, I ran a serial port sniffer and voila all of my
>> printf commands are writing on the serial port.
>>
>
> I can't say that it would cross my mind to look for my missing printf output
> on a serial port, even if I was using a serial port in other parts of the
> program to talk to something.  Whatever it was that gave you the hunch to do
> that is probably at the core of your problem.

My slightly wild guess is that you do an open() on the serial device
without a controlling terminal and without passing the O_NOCTTY flag,
causing the serial device to become your controlling terminal.

~Matt

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