Sometimes, we want to read streaming input from Python subprocess.communicate() method.

In this article, we’ll look at how to read streaming input from Python subprocess.communicate() method.

How to read streaming input from Python subprocess.communicate()?

To read streaming input from Python subprocess.communicate() method, we can use the subprocess.Popen method.

For instance, we write:

from subprocess import Popen, PIPE

with Popen(["ls", "-l"], stdout=PIPE, bufsize=1,
           universal_newlines=True) as p:
    for line in p.stdout:
        print(line, end='')

We call Popen with the command and argument in the list.

And we set stdout to PIPE to pipe the output to p.stdout.

Then we loop through each line in p.stdout and print them with print.

Conclusion

To read streaming input from Python subprocess.communicate() method, we can use the subprocess.Popen method.