topic sys.exit() versus exit() to terminate a standalone script in Python Questions

sys.exit() versus exit() to terminate a standalone script

JoeBorgione — Sat, 11 Dec 2021 08:41:44 GMT

I'm a little confused with the difference between these two approaches and could use some clarification. I have a stand alone python script in which all my geo-processes are enclosed in try/except blocks which is my standard operating procedure. However, in this particular script, if any exceptions are tossed, I want the script to abort. It will be run as a scheduled task.

sys — System-specific parameters and functions — Python 3.8.1 documentation mentions:

sys.exit([arg])https://docs.python.org/3/library/sys.html#sys.exit

Exit from Python. This is implemented by raising the SystemExit exception, so cleanup actions specified by finally clauses of try statements are honored, and it is possible to intercept the exit attempt at an outer level....

...

Since exit() ultimately “only” raises an exception, it will only exit the process when called from the main thread, and the exception is not intercepted.

If I try to use sys.exit in a console I get scolded with:

sys.exit()
An exception has occurred, use %tb to see the full traceback.

SystemExit

C:\EnvClones\arcgispro-py3-clone243\lib\site-packages\IPython\core\interactiveshell.py:3327: UserWarning: To exit: use 'exit', 'quit', or Ctrl-D.
  warn("To exit: use 'exit', 'quit', or Ctrl-D.", stacklevel=1)‍‍‍‍‍‍‍

So using exit() is the clear favorite there. Is sys.exit() preferred in a stand alone script?

Re: sys.exit() versus exit() to terminate a standalone script

JoshuaBixby — Tue, 21 Jan 2020 17:35:56 GMT

Some discussion on StackOverflow: Python exit commands - why so many and when should each be used? - Stack Overflow and Difference between exit() and sys.exit() in Python - Stack Overflow .

Re: sys.exit() versus exit() to terminate a standalone script

JoeBorgione — Tue, 21 Jan 2020 17:50:13 GMT

Thanks- read that too... hence my confusion...

However, reading through it again, the conclusions section states:

Use sys.exit() in scripts, or raise SystemExit() if you prefer.

Re: sys.exit() versus exit() to terminate a standalone script

JoshuaBixby — Tue, 21 Jan 2020 20:06:00 GMT

Yeah, exit() is more for convenience when working interactively in the interpreter, at least that is my very high-level summary.