From 15f11611c138ee5a6256a1ec54be0675e8de63fc Mon Sep 17 00:00:00 2001
From: "Gabriele N. Tornetta" <gabriele.tornetta@datadoghq.com>
Date: Mon, 10 Nov 2025 12:21:12 +0000
Subject: [PATCH] fix: ensure IPC file closed after use

We fix a problem that caused IPC string files to evade proper context
management, leading to spurious ``ResourceWarning``s at runtime.

Fixes #15176.
---
 ddtrace/internal/ipc.py                                    | 7 ++-----
 .../fix-ipc-open-file-ensure-closed-98d9707f56c416da.yaml  | 4 ++++
 2 files changed, 6 insertions(+), 5 deletions(-)
 create mode 100644 releasenotes/notes/fix-ipc-open-file-ensure-closed-98d9707f56c416da.yaml

diff --git a/ddtrace/internal/ipc.py b/ddtrace/internal/ipc.py
index 61bfa2f8e60..03af0886624 100644
--- a/ddtrace/internal/ipc.py
+++ b/ddtrace/internal/ipc.py
@@ -1,4 +1,3 @@
-from contextlib import contextmanager
 import os
 import secrets
 import tempfile
@@ -57,9 +56,7 @@ class ReadLock(BaseUnixLock):
     class WriteLock(BaseUnixLock):
         __acquire_mode__ = fcntl.LOCK_EX
 
-    @contextmanager
-    def open_file(path, mode):
-        yield unpatched_open(path, mode)
+    open_file = unpatched_open
 
 except ModuleNotFoundError:
     # Availability: Windows
@@ -78,7 +75,7 @@ def release(self):
 
     ReadLock = WriteLock = BaseWinLock  # type: ignore
 
-    def open_file(path, mode):
+    def open_file(path, mode):  # type: ignore
         import _winapi
 
         # force all modes to be read/write binary
diff --git a/releasenotes/notes/fix-ipc-open-file-ensure-closed-98d9707f56c416da.yaml b/releasenotes/notes/fix-ipc-open-file-ensure-closed-98d9707f56c416da.yaml
new file mode 100644
index 00000000000..116a58490ce
--- /dev/null
+++ b/releasenotes/notes/fix-ipc-open-file-ensure-closed-98d9707f56c416da.yaml
@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Prevent a potential ``ResourceWarning`` in multiprocess scenarios.