Using subprocess.Popen for Process with Large Output

Question

I have some Python code that executes an external app which works fine when the app has a small amount of output, but hangs when there is a lot. My code looks like:

Answer 1

Here is simple approach which captures both regular output plus error output, all within Python so limitations in stdout don't apply:

com_str = 'uname -a'
command = subprocess.Popen([com_str], stdout=subprocess.PIPE, shell=True)
(output, error) = command.communicate()
print output

Linux 3.11.0-20-generic SMP Fri May 2 21:32:55 UTC 2014 

and

com_str = 'id'
command = subprocess.Popen([com_str], stdout=subprocess.PIPE, shell=True)
(output, error) = command.communicate()
print output

uid=1000(myname) gid=1000(mygrp) groups=1000(cell),0(root)