1

I have a python script. It has a SimpleLogger with sys.stdout as output_stream.

logger = SimpleLogger(level=LogLevel.DEBUG)

When I run it in console, I get the logs properly, but whenever I redirect the output to a file, nothing is found in the target.

I tried multiple ways:

  1. python server.py > /tmp/x.log 2>&1
  2. python server.py > /tmp/x.log

In both cases, the /tmp/x.log is empty.

I also tried nohup python server.py, but nothing has been written in nohup.out.

3

This is probably just due to buffering. You will only see something in the file when enough output has been accumulated. You can try using python -u to ask for unbuffered output, or set environment variable PYTHONUNBUFFERED= to any non-empty string, as documented in the Python command line documentation, or add a .flush() call after each .debug() or similar call.

  • Both solutions worked. Additionally, mentioning buffer remind me of PYTHONUNBUFFERED environment variable. I tried to set it to 1; this solution worked as well. Would you please add this one to your answer? I think the credit is yours, plus it's better to sum the answer up in one place. – Zeinab Abbasimazar Sep 1 '18 at 10:41

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