Caedis Caedis - 2 months ago 19
Python Question

Python OSError: [Errno 2]

I have the following code that is attempting to start each of the "commands" below in Linux. The module attempts to keep each of the 2 commands running if either should crash for whatever reason.

#!/usr/bin/env python
import subprocess

commands = [ ["screen -dmS RealmD top"], ["screen -DmS RealmD top -d 5"] ]
programs = [ subprocess.Popen(c) for c in commands ]
while True:
for i in range(len(programs)):
if programs[i].returncode is None:
continue # still running
# restart this one
programs[i]= subprocess.Popen(commands[i])

Upon executing the code the following exception is thrown:

Traceback (most recent call last):
File "./", line 82, in <module>
programs = [ subprocess.Popen(c) for c in commands ]
File "/usr/lib/python2.6/", line 595, in __init__
errread, errwrite)
File "/usr/lib/python2.6/", line 1092, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory

I think I'm missing something obvious, can anyone see what's wrong with the code above?

sth sth

Use ["screen", "-dmS", "RealmD", "top"] instead of ["screen -dmS RealmD top"].

Maybe also use the complete path to screen.

If the program still cannot be found you can also go through your shell with shell=True, but then you need to quote and escape your parameters etc. Make sure to read the information in the docs if you plan to do that.