What should go to stdout/stderr and why Python logging write everything to stderr?

[Weatherby,Gerard]

Dealing with stdout / stderr is bash is just syntax. I don’t always remember it off the top of my head but … stackoverflow.com.

On Linux at least it’s possible to pipe to arbitrary streams, it seems. The following uses bash to write “Hi” to the file “third” opened by Python. I determined the file was 5 empirically.


import os
import subprocess
command= 'echo Hi >/dev/fd/5'
fd = os.open("third",os.O_WRONLY|os.O_CREAT)
os.set_inheritable(fd,True)

subprocess.run(('/usr/bin/bash','-c',command),close_fds=False)

From: Python-list <python-list-bounces+gweatherby=uchc.edu at python.org> on behalf of Michael Torrie <torriem at gmail.com>
Date: Tuesday, January 3, 2023 at 5:18 PM
To: python-list at python.org <python-list at python.org>
Subject: Re: What should go to stdout/stderr and why Python logging write everything to stderr?
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Maybe some day an interface and shell syntax will be developed to
interact with an arbitrary number of standard streams.  Current piping
syntax really only works well with one stream and even trying to use
stderr and stdout with pipes and filters in a shell is awkward.




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