diff -r d31b4de433b7 Doc/library/os.rst
--- a/Doc/library/os.rst	Tue Sep 20 23:00:59 2016 +0200
+++ b/Doc/library/os.rst	Tue Sep 20 23:06:42 2016 +0200
@@ -3953,6 +3953,14 @@ Random numbers
    following values ORed together: :py:data:`os.GRND_RANDOM` and
    :py:data:`GRND_NONBLOCK`.
 
+   The function can raise an :exc:`OSError` exception with the error number
+   :data:`errno.ENOSYS`` if the Linux kernel does not support the
+   :c:func:`getrandom` syscall.
+
+   The function can raise an :exc:`OSError` exception with the error number
+   :data:`errno.EPERM`` if the :c:func:`getrandom` syscall is blocked, by a
+   SECCOMP policy for example.
+
    See also the `Linux getrandom() manual page
    <http://man7.org/linux/man-pages/man2/getrandom.2.html>`_.