How to get exit code when using Python subprocess communicate method?

python, subprocess

Solution

`Popen.communicate` will set the `returncode` attribute when it's done(*). Here's the relevant documentation section:

Popen.returncode 
  The child return code, set by poll() and wait() (and indirectly by communicate()). 
  A None value indicates that the process hasn’t terminated yet.

  A negative value -N indicates that the child was terminated by signal N (Unix only).

So you can just do (I didn't test it but it should work):

import subprocess as sp
child = sp.Popen(openRTSP + opts.split(), stdout=sp.PIPE)
streamdata = child.communicate()[0]
rc = child.returncode

(*) This happens because of the way it's implemented: after setting up threads to read the child's streams, it just calls `wait`.

Problem

How do I retrieve the exit code when using Python's `subprocess` module and the `communicate()` method? Relevant code: ``` import subprocess as sp data = sp.Popen(openRTSP + opts.split(), stdout=sp.PIPE).communicate()[0] ``` Should I be doing this another way?

Original source