How to execute a UNIX command in Python script

Question

#!/usr/bin/python

import os
import shutil
import commands
import time
import copy

name = 'test'

echo name 

I have a simple python scripts like the above. When I attempt to execute it I get a syntax error when trying to output the name variable.

Answer 1

You cannot use UNIX commands in your Python script as if they were Python code, echo name is causing a syntax error because echo is not a built-in statement or function in Python. Instead, use print name.

To run UNIX commands you will need to create a subprocess that runs the command. The simplest way to do this is using os.system(), but the subprocess module is preferable.

Answer 2

you can also use subprocess module.

import subprocess
proc = subprocess.Popen(['echo', name],
                            stdin = subprocess.PIPE,
                            stdout = subprocess.PIPE,
                            stderr = subprocess.PIPE
                        )

(out, err) = proc.communicate()
print out

Read: http://www.doughellmann.com/PyMOTW/subprocess/