How to use shell variables within a python script

Question

I'd like to get shell variable content to be used within a python script, specifically to get path out of it to be used later for a function call to a python script located at another directory, using sys.path.insert

Let's assume my shell variable is called SHELL_VAR1, and I want to concatenate to it /scripts folder name, so I get flow like that - using in this example os.environ.get just to illustrate my need in case it was environment variable and not a shell variable - and the question is what should be used instead:

python -c 'import os; import sys;var1=os.environ.get('SHELL_VAR1'); sys.path.insert(1, 'var1' ''/scripts'');'

Does this answer your question? [How to call an external command?](https://stackoverflow.com/questions/89228/how-to-call-an-external-command) — Inder, Sep 15 '20 at 16:22
No, as far as I see, since I want to embed the result within the python script -Jakob's answer below helped me, thanks — GM1, Sep 15 '20 at 16:53
and the question there is more generalized than mine, so I get 'lost' with the answers... — GM1, Sep 15 '20 at 17:04

score 1 · Accepted Answer · answered Sep 15 '20 at 16:21

A shell variable and environment variable are the same thing, in my understanding.

You can use pathlib for OS-agnostic filepath operations (like joining filepaths).

import os
from pathlib import Path
import sys

# This will raise a KeyError if the key is not in os.environ.
var1 = os.environ["SHELL_VAR1"]
path = Path(var1) / "scripts"
sys.path.insert(1, str(path))

How to use shell variables within a python script

1 Answers1