How to get PID of the subprocess with subprocess check_output

Question

In my python script I'm trying to run some long lasting download process, like in the example below, and need to find a PID of the process started by check_output:

out = subprocess.check_output(["rsync","-azh","file.log",...])

Is it possible to do?

Answer 1

You can run your subprocess using Popen instead:

import subprocess
proc = subprocess.Popen(["rsync","-azh","file.log",...], stdout=subprocess.PIPE)
out = proc.communicate()[0]
pid = proc.pid

Generally, Popen object gives you better control and more info of the subprocess, but requires a bit more to setup. (Not much, though.) You can read more in the official documentation.