From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Thu, 22 Sep 2022 17:24:54 +0000 (-0700)
Subject: GH-85760: Fix race in calling process_exited callback too early (GH-97009)
X-Git-Tag: v3.11.1~452
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=6642d8a0f9f3fb1e9594883c3ddcb135a580f223;p=thirdparty%2FPython%2Fcpython.git

GH-85760: Fix race in calling process_exited callback too early (GH-97009)

(cherry picked from commit 282edd7b2a74c4dfe1bfe3c5b1d30f9c21d554d6)

Co-authored-by: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
---

diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py
index cf7683fee646..96e6d73a7597 100644
--- a/Lib/asyncio/unix_events.py
+++ b/Lib/asyncio/unix_events.py
@@ -223,7 +223,8 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
         return transp
 
     def _child_watcher_callback(self, pid, returncode, transp):
-        self.call_soon_threadsafe(transp._process_exited, returncode)
+        # Skip one iteration for callbacks to be executed
+        self.call_soon_threadsafe(self.call_soon, transp._process_exited, returncode)
 
     async def create_unix_connection(
             self, protocol_factory, path=None, *,
diff --git a/Misc/NEWS.d/next/Library/2022-09-22-11-50-29.gh-issue-85760.DETTPd.rst b/Misc/NEWS.d/next/Library/2022-09-22-11-50-29.gh-issue-85760.DETTPd.rst
new file mode 100644
index 000000000000..af8ae2026f16
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-09-22-11-50-29.gh-issue-85760.DETTPd.rst
@@ -0,0 +1 @@
+Fix race condition in :mod:`asyncio` where :meth:`~asyncio.SubprocessProtocol.process_exited` called before the :meth:`~asyncio.SubprocessProtocol.pipe_data_received` leading to inconsistent output. Patch by Kumar Aditya.