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Re: Unbuffered stderr in Python 3

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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.
>
>
>

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Thread

Unbuffered stderr in Python 3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-11-02 18:52 +1100
  Re: Unbuffered stderr in Python 3 Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-11-02 11:48 +0100
  Re: Unbuffered stderr in Python 3 Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-11-02 11:54 +0100
  Re: Unbuffered stderr in Python 3 Nobody <nobody@nowhere.invalid> - 2015-11-03 07:10 +0000
    Re: Unbuffered stderr in Python 3 Random832 <random832@fastmail.com> - 2015-11-03 10:00 -0500
    Re: Unbuffered stderr in Python 3 Chris Angelico <rosuav@gmail.com> - 2015-11-04 02:42 +1100
    Re: Unbuffered stderr in Python 3 Terry Reedy <tjreedy@udel.edu> - 2015-11-03 17:25 -0500
      Re: Unbuffered stderr in Python 3 Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-11-04 14:18 +1100
        Re: Unbuffered stderr in Python 3 Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-11-04 09:19 +0100
          Re: Unbuffered stderr in Python 3 Steven D'Aprano <steve@pearwood.info> - 2015-11-04 21:24 +1100
            Re: Unbuffered stderr in Python 3 Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-11-04 11:43 +0100
            Re: Unbuffered stderr in Python 3 Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-11-04 12:49 +0100
            Re: Unbuffered stderr in Python 3 Random832 <random832@fastmail.com> - 2015-11-04 08:43 -0500
        Re: Unbuffered stderr in Python 3 Terry Reedy <tjreedy@udel.edu> - 2015-11-04 18:00 -0500
  Re: Unbuffered stderr in Python 3 srinivas devaki <mr.eightnoteight@gmail.com> - 2015-11-06 19:10 +0530

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