Difference between subprocess.Popen and os.system

python subprocess system
Arovit picture Arovit · Jan 27, 2011 · Viewed 99.8k times · Source

What is the difference between subprocess.Popen() and os.system()?

Answer

Jacob Marble picture Jacob Marble · Jan 27, 2011

If you check out the subprocess section of the Python docs, you'll notice there is an example of how to replace os.system() with subprocess.Popen():

sts = os.system("mycmd" + " myarg")

...does the same thing as...

sts = Popen("mycmd" + " myarg", shell=True).wait()

The "improved" code looks more complicated, but it's better because once you know subprocess.Popen(), you don't need anything else. subprocess.Popen() replaces several other tools (os.system() is just one of those) that were scattered throughout three other Python modules.

If it helps, think of subprocess.Popen() as a very flexible os.system().

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