From 5b318cae7d3c425d9bf56d1e1299f043b5a3c14a 2015-10-27 15:33:07
From: John Kirkham <kirkhamj@janelia.hhmi.org>
Date: 2015-10-27 15:33:07
Subject: [PATCH] IPython/utils/io.py: Make sure `devnull` is closed at exit to avoid a `ResourceWarning` being raised by Python 3.

---

diff --git a/IPython/utils/io.py b/IPython/utils/io.py
index 5b0fdb2..2ba3fd5 100644
--- a/IPython/utils/io.py
+++ b/IPython/utils/io.py
@@ -10,6 +10,7 @@ from __future__ import print_function
 from __future__ import absolute_import
 
 
+import atexit
 import os
 import sys
 import tempfile
@@ -73,6 +74,7 @@ class IOStream:
 
 # setup stdin/stdout/stderr to sys.stdin/sys.stdout/sys.stderr
 devnull = open(os.devnull, 'w') 
+atexit.register(devnull.close)
 stdin = IOStream(sys.stdin, fallback=devnull)
 stdout = IOStream(sys.stdout, fallback=devnull)
 stderr = IOStream(sys.stderr, fallback=devnull)