1

I am trying to redirect the output of certain program with threads to certain file.

I have tried running command > file 2&>1 but if command has not stopped running, file will still be empty.

Is there any way to asynchronously dump the output to file?

Example python snippet:

import _thread

def run():
    raise ValueError('plah')

_thread.start_new_thread(run, ())
while True:
    pass

Running python program.py 2> log.txt does not yield an output in log.txt until the program is manually stopped.

countermode
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Lezkus
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2 Answers2

2

Make the output unbuffered. A simple way to do this with Python is to set PYTHONUNBUFFERED:

PYTHONUNBUFFERED=1 python program.py 2>log.txt
Community
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Satō Katsura
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1

Python buffers output by default. Give the -u flag, or put PYTHONUNBUFFERED=yes to avoid that.

Göran Uddeborg
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