How can I check to see if a Python script was started interactively?

Question

I'd like for a script of mine to have 2 behaviours, one when started as a scheduled task, and another if started manually. How could I test for interactiveness?

EDIT: this could either be a cron job, or started by a windows batch file, through the scheduled tasks.

Answer 1

You should simply add a command-line switch in the scheduled task, and check for it in your script, modifying the behavior as appropriate. Explicit is better than implicit.

One benefit to this design: you'll be able to test both behaviors, regardless of how you actually invoked the script.

Answer 2

If you want to know if you're reading from a terminal (not clear if that is enough of a distinction, please clarify) you can use

sys.stdin.isatty()

Answer 3

I'd just add a command line switch when you're calling it with cron:

python yourscript.py -scheduled

then in your program

import sys

if "-scheduled" in sys.argv:
    #--non-interactive code--
else: 
    #--interactive code--