Running bash commands in Python: os vs subprocess?

Subprocess gives you much more control over what's going on.

For example, you can redirect output to pipe it to your program like that:

process = subprocess.Popen(['ls', '-a'], stdout=subprocess.PIPE)
out, err = process.communicate()

(Example from python getoutput() equivalent in subprocess)

If you used system() you'd have to do redirection of input, saving it to file and weird things like that.

In documentation for os.system (https://docs.python.org/2/library/os.html#os.system) it is said that:

The subprocess module provides more powerful facilities for spawning new processes and retrieving their results; using that module is preferable to using this function. See the Replacing Older Functions with the subprocess Module section in the subprocess documentation for some helpful recipes.