How to determine pid of process started via os.system

Question

I want to start several subprocesses with a programm, i.e. a module foo.py starts several instances of bar.py.

Since I sometimes have to te

Answer 1

os.system return exit code. It does not provide pid of the child process.

Use subprocess module.

import subprocess
import time
argument = '...'
proc = subprocess.Popen(['python', 'bar.py', argument], shell=True)
time.sleep(3) # <-- There's no time.wait, but time.sleep.
pid = proc.pid # <--- access `pid` attribute to get the pid of the child process.

To terminate the process, you can use terminate method or kill. (No need to use external kill program)

proc.terminate()