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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 Mon, 2 Nov 2015 11:54:44 +0100
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On 02.11.2015 11:48, Wolfgang Maier wrote:
>
> Since Python3.3, the print function has a flush keyword argument that
> accepts a boolean and lets you do just this. Rewrite your example as:
>
> import sys, time
>
> def test():
> # Simulate a slow calculation that prints status and/or error
> # messages to stderr.
> for i in range(10):
> _print(i, file=sys.stderr, end="", flush=True)
> time.sleep(2)
> print("", file=sys.stderr)
>
> and it should do what you want.

sorry for this mess (copy pasted from the wrong source).
The code should be:

def test():
     # Simulate a slow calculation that prints status and/or error
     # messages to stderr.
     for i in range(10):
         print(i, file=sys.stderr, end="", flush=True)
         time.sleep(2)
     print("", file=sys.stderr)

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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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