Issue #25654:

* multiprocessing: open file with closefd=False to avoid ResourceWarning
* _test_multiprocessing: open file with O_EXCL to detect bugs in tests (if a
  previous test forgot to remove TESTFN)
* test_sys_exit(): remove TESTFN after each loop iteration

Initial patch written by Serhiy Storchaka.

1 files changed, 1 insertions, 1 deletions

diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 8209ae9..684a59f 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -2689,7 +2689,7 @@ Beware of replacing :data:`sys.stdin` with a "file like object"
     in issues with processes-in-processes. This has been changed to::
 
         sys.stdin.close()
-        sys.stdin = open(os.devnull)
+        sys.stdin = open(os.open(os.devnull, os.O_RDONLY), closefd=False)
 
     Which solves the fundamental issue of processes colliding with each other
     resulting in a bad file descriptor error, but introduces a potential danger