From 93fdf4366a9bfe1336892d0388c56d0e03b2f8aa Mon Sep 17 00:00:00 2001
From: AN Long <aisk@users.noreply.github.com>
Date: Mon, 28 Jul 2025 19:55:59 +0900
Subject: [PATCH] gh-119711: describe `create_datagram_endpoint`'s behavior in
 asyncio when `local_addr` is `None` (GH-136913) (cherry picked from commit
 1481384141342479b3ba4b89f653b4e5bef0d272)

Co-authored-by: AN Long <aisk@users.noreply.github.com>
---
 Doc/library/asyncio-eventloop.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Doc/library/asyncio-eventloop.rst b/Doc/library/asyncio-eventloop.rst
index 91970c282391f7..9561c40776f01c 100644
--- a/Doc/library/asyncio-eventloop.rst
+++ b/Doc/library/asyncio-eventloop.rst
@@ -611,6 +611,12 @@ Opening network connections
      to bind the socket locally.  The *local_host* and *local_port*
      are looked up using :meth:`getaddrinfo`.
 
+     .. note::
+
+        On Windows, when using the proactor event loop with ``local_addr=None``,
+        an :exc:`OSError` with :attr:`!errno.WSAEINVAL` will be raised
+        when running it.
+
    * *remote_addr*, if given, is a ``(remote_host, remote_port)`` tuple used
      to connect the socket to a remote address.  The *remote_host* and
      *remote_port* are looked up using :meth:`getaddrinfo`.