From 1d16229f3f5b91f2389c7c5c6425c5524c413651 Mon Sep 17 00:00:00 2001
From: "Miss Islington (bot)"
 <31488909+miss-islington@users.noreply.github.com>
Date: Mon, 3 Aug 2020 18:00:29 -0700
Subject: [PATCH] bpo-41467: Fix asyncio recv_into() on Windows (GH-21720)

On Windows, fix asyncio recv_into() return value when the socket/pipe
is closed (BrokenPipeError): return 0 rather than an empty byte
string (b'').
(cherry picked from commit 602a971a2af3a685d625c912c400cadd452718b1)

Co-authored-by: Victor Stinner <vstinner@python.org>
---
 Lib/asyncio/windows_events.py                                  | 2 +-
 .../next/Library/2020-08-04-00-20-30.bpo-41467.Z8DgTL.rst      | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Library/2020-08-04-00-20-30.bpo-41467.Z8DgTL.rst

diff --git a/Lib/asyncio/windows_events.py b/Lib/asyncio/windows_events.py
index c07fe3241c569a..a6759b78bd801f 100644
--- a/Lib/asyncio/windows_events.py
+++ b/Lib/asyncio/windows_events.py
@@ -469,7 +469,7 @@ def recv_into(self, conn, buf, flags=0):
             else:
                 ov.ReadFileInto(conn.fileno(), buf)
         except BrokenPipeError:
-            return self._result(b'')
+            return self._result(0)
 
         def finish_recv(trans, key, ov):
             try:
diff --git a/Misc/NEWS.d/next/Library/2020-08-04-00-20-30.bpo-41467.Z8DgTL.rst b/Misc/NEWS.d/next/Library/2020-08-04-00-20-30.bpo-41467.Z8DgTL.rst
new file mode 100644
index 00000000000000..f12693e117631a
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-08-04-00-20-30.bpo-41467.Z8DgTL.rst
@@ -0,0 +1,3 @@
+On Windows, fix asyncio ``recv_into()`` return value when the socket/pipe is
+closed (:exc:`BrokenPipeError`): return ``0`` rather than an empty byte
+string (``b''``).