printf goes to serial port?

Alex Martin
Fri Dec 19 20:19:00 GMT 2008

Well, I was using a port monitor to debug some of the traffic between my 
serial device, and my software, when I noticed the output accidentally.

I am not sure when the behavior started. It used to work fine, I was 
using printf to debug things, then I turned off all of those printf 
statements, and continued development on the gui side (fox toolkit) of 
my application, and then had to go in and modify my low level serial 
class and was trying to get my printf debug output again, to no avail.

I have updated cygwin a few times, otherwise I cannot think of anything 

What other details can I provide?

Alex Martin

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.
>> Any idea how to fix this?
> Well, no, not really, since you've given very few details to go on.  I'd
> SWAG that you've somewhere, somehow, redirected stdout to the serial port
> you're trying to talk to those devices on.
>> Thanks,
>> Alex Martin

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