Determine if the program is called from a script in Python

Question

doa

#!/bin/sh
myexe

myexe

if sys.stdout.isatty():
    print 'from a script'
else:
    print 'not from a script'

OUTPUT (if i execute doa from terminal):

not from a script

OUTPUT (if i execute myexe from terminal):

not from a script

I want it to say 'from a script' if executed from doa

Question: is it possible for myexe to know that it's being executed from a bash script?

I don't know of a way to detect if the files been called from a script (In theory, it is always called by a script, be it a batch script, the command line, of your mouse double clicking on it). You could instead pass it a parameter from the script to detect with sys.argv[index] and tell it where it has been called from. — NDevox
– NDevox, Commented Mar 24, 2015 at 18:00
A bash script as opposed to what? Your sh script? An interactive shell? When does it matter? — that other guy
– that other guy, Commented Mar 24, 2015 at 18:01
Seeing if stdout is a TTY is a common, sensible check because it lets you decide whether to output in a human-readable or computer-readable format (e.g., colored output when connected to a TTY, plain output when piped to another process). But checking how your program is invoked... what would you do differently based on the identity of the parent process–and why? — John Kugelman
– John Kugelman, Commented Mar 24, 2015 at 18:01
I'm pretty sure the answer is no. What problem are you really trying to solve? — Steven Rumbalski
– Steven Rumbalski, Commented Mar 24, 2015 at 18:04

JuniorCompressor · Accepted Answer · 2015-03-24 18:06:53Z

5

You can use psutil to ask for the name of the process with id the parent process id:

import psutil
import os

ppid = os.getppid() # Get parent process id
psutil.Process(ppid).name() == "bash"

You can install psutil with pip command:

pip install psutil

answered Mar 24, 2015 at 18:06

JuniorCompressor

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4 Comments

If the user's console is also bash, then this won't be able to determine if it is being run from a script or if it's run directly from the console...

i know i gave bash as an example but i want to encompasses whole script. myexe can be called from another python script or whatnot

@BillLynch can you check if the user console is bash or not and then compare against it? oh wait nvm.. hmm..

@ealeon: You can usually tell if the user console is bash by checking $SHELL. But personally, all of this is a bad idea.