Can I redirect the stdout in python into some sort of string buffer?

python stream stdout redirect
Avihu Turzion picture Avihu Turzion · Aug 2, 2009 · Viewed 128.3k times · Source

I'm using python's ftplib to write a small FTP client, but some of the functions in the package don't return string output, but print to stdout. I want to redirect stdout to an object which I'll be able to read the output from.

I know stdout can be redirected into any regular file with:

stdout = open("file", "a")

But I prefer a method that doesn't uses the local drive.

I'm looking for something like the BufferedReader in Java that can be used to wrap a buffer into a stream.

Answer

Ned Batchelder picture Ned Batchelder · Aug 2, 2009 
from cStringIO import StringIO # Python3 use: from io import StringIO
import sys

old_stdout = sys.stdout
sys.stdout = mystdout = StringIO()

# blah blah lots of code ...

sys.stdout = old_stdout

# examine mystdout.getvalue()

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