Python os.system without the output

python subprocess os.system
user697108 picture user697108 · Apr 8, 2011 · Viewed 60.8k times · Source

I'm running this:

os.system("/etc/init.d/apache2 restart")

It restarts the webserver, as it should, and like it would if I had run the command directly from the terminal, it outputs this:

* Restarting web server apache2 ... waiting [ OK ]

However, I don't want it to actually output it in my app. How can I disable it? Thanks!

Answer

lunaryorn picture lunaryorn · Apr 8, 2011

Avoid os.system() by all means, and use subprocess instead:

with open(os.devnull, 'wb') as devnull:
    subprocess.check_call(['/etc/init.d/apache2', 'restart'], stdout=devnull, stderr=subprocess.STDOUT)

This is the subprocess equivalent of the /etc/init.d/apache2 restart &> /dev/null.

There is subprocess.DEVNULL on Python 3.3+:

#!/usr/bin/env python3
from subprocess import DEVNULL, STDOUT, check_call

check_call(['/etc/init.d/apache2', 'restart'], stdout=DEVNULL, stderr=STDOUT)

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