# HG changeset patch
# Parent 45ba5de2711b63fbf03426bab7a9a9c6d13da811
diff -r 45ba5de2711b -r 1111e45304e5 Doc/library/exceptions.rst
--- a/Doc/library/exceptions.rst	Sat Feb 07 15:42:53 2015 -0800
+++ b/Doc/library/exceptions.rst	Sun Feb 08 02:44:24 2015 +0000
@@ -259,6 +259,15 @@
    :attr:`filename2` attribute corresponding to the second file name passed
    to the function.
 
+   If two arguments are passed to the constructor, the first is available as
+   the :attr:`errno` attribute, and the second is available as
+   the :attr:`strerror` attribute.  Otherwise, these attributes default to
+   :const:`None`.  When a third argument is also passed, it is available as
+   the :attr:`filename` attribute, otherwise it also defaults to
+   :const:`None`.  For backwards compatibility, if three arguments are
+   passed, the :attr:`~BaseException.args` attribute contains only a 2-tuple
+   of the first two constructor arguments.
+
 
    .. versionchanged:: 3.3
       :exc:`EnvironmentError`, :exc:`IOError`, :exc:`WindowsError`,