bpo-44508: [Doc] Document failure mode for loop.call_soon_threadsafe (GH-27688) ...

Co-authored-by: Łukasz Langa <lukasz@langa.pl>
(cherry picked from commit 3240bc62f4e0afa09964f3afc845697f0a0806b9)

Co-authored-by: meowmeowmeowcat <meowmeowcat1211@gmail.com>

diff --git a/Doc/library/asyncio-eventloop.rst b/Doc/library/asyncio-eventloop.rst
index 66eb3faecd896e1d801989f03fe6039b7b4920dd..4a64475f2a939ee467cbe31eba0dde7b8e21d604 100644 (file)
--- a/Doc/library/asyncio-eventloop.rst
+++ b/Doc/library/asyncio-eventloop.rst
@@ -211,6 +211,10 @@ Scheduling callbacks
    A thread-safe variant of :meth:`call_soon`.  Must be used to
    schedule callbacks *from another thread*.
 
+   Raises :exc:`RuntimeError` if called on a loop that's been closed.
+   This can happen on a secondary thread when the main application is
+   shutting down.
+
    See the :ref:`concurrency and multithreading <asyncio-multithreading>`
    section of the documentation.