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From: srinivas devaki <mr.eightnoteight@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Unbuffered stderr in Python 3
Date: Fri, 6 Nov 2015 19:10:07 +0530
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On Mon, Nov 2, 2015 at 1:22 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
>
> So how come Python 3 has line buffered stderr? And more importantly, how can
> I turn buffering off?
>
> I don't want to use the -u unbuffered command line switch, because that
> effects stdout as well. I'm happy for stdout to remain buffered.
>
you can simply turn buffering off for stderr by redefining the print
function or declaring a new print function like


from functools import partial
print = partial(print, flush=True)
# or
from functools import partial
import sys
printerr = partial(print, flush=True, file=sys.stderr)