Python Script execute commands in Terminal

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I read this somewhere a while ago but cant seem to find it. I am trying to find a command that will execute commands in the terminal and then output the result.

For example: the script will be:

command 'ls -l'

It will out the result of running that command in the terminal

11 Answers
import os
os.system("echo 'hello world'")

This should work. I do not know how to print the output into the python Shell.

for python3 use subprocess

import subprocess
s = subprocess.getstatusoutput(f'ps -ef | grep python3')
print(s)

You can also check for errors:

import subprocess
s = subprocess.getstatusoutput('ls')
if s[0] == 0:
    print(s[1])
else:
    print('Custom Error {}'.format(s[1]))


# >>> Applications
# >>> Desktop
# >>> Documents
# >>> Downloads
# >>> Library
# >>> Movies
# >>> Music
# >>> Pictures
import subprocess
s = subprocess.getstatusoutput('lr')
if s[0] == 0:
    print(s[1])
else:
    print('Custom Error: {}'.format(s[1]))

# >>> Custom Error: /bin/sh: lr: command not found

In python3 the standard way is to use subprocess.run

res = subprocess.run(['ls', '-l'], capture_output=True)
print(res.stdout)

Jupyter

In a jupyter notebook you can use the magic function !

!echo "execute a command"
files = !ls -a /data/dir/ #get the output into a variable

ipython

To execute this as a .py script you would need to use ipython

files = get_ipython().getoutput('ls -a /data/dir/')

execute script

$ ipython my_script.py

You could import the 'os' module and use it like this :

import os
os.system('#DesiredAction')
  • Running: subprocess.run
  • Output: subprocess.PIPE
  • Error: raise RuntimeError

#! /usr/bin/env python3
import subprocess


def runCommand (command):
    output=subprocess.run(
        command,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE)

    if output.returncode != 0:
        raise RuntimeError(
            output.stderr.decode("utf-8"))

    return output


output = runCommand ([command, arguments])
print (output.stdout.decode("utf-8"))
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