Merge pull request matplotlib#6193 from KanwarGill/mkdtempfix

MNT: Make use of mkdtemp when creating temporary config directory.

Fix matplotlib#4597

Author: tacaswell

lib/matplotlib/__init__.py

@@ -553,16 +553,14 @@ def _create_tmp_config_dir():
         # Some restricted platforms (such as Google App Engine) do not provide
         # gettempdir.
         return None
-
     try:
         username = getpass.getuser()
     except KeyError:
         username = str(os.getuid())
-    tempdir = os.path.join(tempdir, 'matplotlib-%s' % username)
 
-    os.environ['MPLCONFIGDIR'] = tempdir
+    tempdir = tempfile.mkdtemp(prefix='matplotlib-%s-' % username, dir=tempdir)
 
-    mkdirs(tempdir)
+    os.environ['MPLCONFIGDIR'] = tempdir
 
     return tempdir