How to call a shell script from python code?

Question

The subprocess module will help you out.

Blatantly trivial example:

>>> import subprocess
>>> subprocess.call(['sh', './test.sh']) # Thanks @Jim Dennis for suggesting the []
0 
>>> 

Where test.sh is a simple shell script and 0 is its return value for this run.

There are some ways using os.popen() (deprecated) or the whole subprocess module, but this approach

import os
os.system(command)

is one of the easiest.

In case you want to pass some parameters to your shell script, you can use the method shlex.split():

import subprocess
import shlex
subprocess.call(shlex.split('./test.sh param1 param2'))

with test.sh in the same folder:

#!/bin/sh
echo $1
echo $2
exit 0

Outputs:

$ python test.py 
param1
param2

import os
import sys

Assuming test.sh is the shell script that you would want to execute

os.system("sh test.sh")

I'm running python 3.5 and subprocess.call(['./test.sh']) doesn't work for me.

I give you three solutions depends on what you wanna do with the output.

1 - call script. You will see output in your terminal. output is a number.

import subprocess 
output = subprocess.call(['test.sh'])

2 - call and dump execution and error into string. You don't see execution in your terminal unless you print(stdout). Shell=True as argument in Popen doesn't work for me.

import subprocess
from subprocess import Popen, PIPE

session = subprocess.Popen(['test.sh'], stdout=PIPE, stderr=PIPE)
stdout, stderr = session.communicate()

if stderr:
    raise Exception("Error "+str(stderr))

3 - call script and dump the echo commands of temp.txt in temp_file

import subprocess
temp_file = open("temp.txt",'w')
subprocess.call([executable], stdout=temp_file)
with open("temp.txt",'r') as file:
    output = file.read()
print(output)

Don't forget to take a look at the doc subprocess

Use the subprocess module as mentioned above.

I use it like this:

subprocess.call(["notepad"])

I know this is an old question but I stumbled upon this recently and it ended up misguiding me since the Subprocess API as changed since python 3.5.

The new way to execute external scripts is with the run function, which runs the command described by args. Waits for command to complete, then returns a CompletedProcess instance.

import subprocess

subprocess.run(['./test.sh'])