How To Write An Output Of A Command To Stdout And A File In Python3?

I have a Windows command which I want to write to stdout and to a file. For now, I only have 0 string writen in my file: #!/usr/bin/env python3 #! -*- coding:utf-8 -*- import subp

Solution 1:

subprocess.call returns an int (the returncode) and that's why you have 0 written in your file. If you want to capture the output, why don't you use subprocess.run instead?

import subprocess

cmd = ['netsh', 'interface', 'show', 'interface']
p = subprocess.run(cmd, stdout=subprocess.PIPE)
with open('my_file.txt', 'wb') as f:
    f.write(p.stdout)

In order to capture the output in p.stdout, you'll have to redirect stdout to subprocess.PIPE. Now p.stdout holds the output (in bytes), which you can save to file.

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Another option for Python versions < 3.5 is subprocess.Popen. The main difference for this case is that .stdout is a file object, so you'll have to read it.

import subprocess

cmd = ['netsh', 'interface', 'show', 'interface']
p = subprocess.Popen(cmd, stdout=subprocess.PIPE)
out = p.stdout.read()
#print(out.decode())  
with open('my_file.txt', 'wb') as f:
    f.write(out)