Difference between .Popen and os.system subprocess

Question

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

Answer 1

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

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

... does the same as ...

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

The "improved" code looks more complex, but better, because as soon as you know subprocess.Popen() , you don't need anything else. subprocess.Popen() replaces several other tools ( os.system() is just one of them) that were scattered across three other Python modules.

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

Answer 2

subprocess.Popen () is a strict superset of os.system ().

Answer 3

The subprocess is based on popen2, and as such has a number of advantages - there is a complete list in

Answer 4

os.system is equivalent to the Unix system command, while the subprocess was a helper module designed to provide many of the features provided by the Popen commands with a simpler and more manageable interface. They were similar to the Unix Popen team.

 system() executes a command specified in command by calling /bin/sh -c command, and returns after the command has been completed 

where as

 The popen() function opens a process by creating a pipe, forking, and invoking the shell. 

If you are thinking which one to use, then use the subprocess specifically because you have all the options to execute, plus additional control over the process.