Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de>
Newsgroups: comp.lang.python
Subject: Re: Unbuffered stderr in Python 3
Date: Wed, 4 Nov 2015 11:43:18 +0100
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On 04.11.2015 11:24, Steven D'Aprano wrote:
> On Wed, 4 Nov 2015 07:19 pm, Wolfgang Maier wrote:
>
>> On 04.11.2015 04:18, Steven D'Aprano wrote:
>>>
>>> This is one of the offending line from our code base:
>>>
>>> print('<4>Suspicious answer "{}"!'.format(answer), file=sys.stderr)
>>>
>>> So that ought to be terminated by a newline. And yet, the stderr output
>>> doesn't show up until the program exits.
>>>
>>
>> For me, that prints immediately. Where is your output going? Console,
>> file, ...?
>
> Going to stderr, like the whole thread is about :-)
>

I see :), but seriously, what I meant was: is it going to the console 
directly or is your code base redirecting sys.stderr to another buffered 
object first?

>
> The output does eventually show up written to the console, but only after
> Python exits.
>
>
>