The Python Oracle

How do I detect whether sys.stdout is attached to terminal or not?

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Chapters
00:00 Question
00:41 Accepted answer (Score 270)
01:10 Thank you

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Full question
https://stackoverflow.com/questions/1077...

Accepted answer links:
[isatty]: https://docs.python.org/3/library/io.htm...

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Tags
#python #console #terminal

#avk47


ACCEPTED ANSWER

Score 295


This can be detected using isatty:

if sys.stdout.isatty():
    # You're running in a real terminal
else:
    # You're being piped or redirected

To demonstrate this in a shell:

  • python -c "import sys; print(sys.stdout.isatty())" should write True
  • python -c "import sys; print(sys.stdout.isatty())" | cat should write False