How can I get terminal output in python?

Question

This question already has answers here:

Running shell command and capturing the output (19 answers)

Closed 6 years ago.

I can execute a terminal command using os.system() but I want to capture the output of this command. How can I do this?

Answer 1

>>> import subprocess
>>> cmd = [ 'echo', 'arg1', 'arg2' ]
>>> output = subprocess.Popen( cmd, stdout=subprocess.PIPE ).communicate()[0]
>>> print output
arg1 arg2

>>> 

There is a bug in using of the subprocess.PIPE. For the huge output use this:

import subprocess
import tempfile

with tempfile.TemporaryFile() as tempf:
    proc = subprocess.Popen(['echo', 'a', 'b'], stdout=tempf)
    proc.wait()
    tempf.seek(0)
    print tempf.read()

Answer 2

The recommended way in Python 3.5 and above is to use subprocess.run():

from subprocess import run
output = run("pwd", capture_output=True).stdout

Answer 3

You can use Popen in subprocess as they suggest.

with os, which is not recomment, it's like below:

import os
a  = os.popen('pwd').readlines()

Answer 4

The easiest way is to use the library commands

import commands
print commands.getstatusoutput('echo "test" | wc')