read subprocess stdout line by line

Question

My python script uses subprocess to call a linux utility that is very noisy. I want to store all of the output to a log file and show some of it to the user. I thought the

Answer 1

Bit late to the party, but was surprised not to see what I think is the simplest solution here:

import io
import subprocess

proc = subprocess.Popen(["prog", "arg"], stdout=subprocess.PIPE)
for line in io.TextIOWrapper(proc.stdout, encoding="utf-8"):  # or another encoding
    # do something with line

(This requires Python 3.)