bpo-4928: Document NamedTemporaryFile non-deletion after SIGKILL (#26198)

* bpo-4928 Document NamedTemporaryFile non-deletion after SIGKILL

* 📜🤖 Added by blurb_it.

Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com>

Doc/library/tempfile.rst

@@ -87,6 +87,9 @@ The module defines the following user-callable items:
    attribute is the underlying true file object. This file-like object can
    be used in a :keyword:`with` statement, just like a normal file.
 
+   On POSIX (only), a process that is terminated abruptly with SIGKILL
+   cannot automatically delete any NamedTemporaryFiles it created.
+
    .. audit-event:: tempfile.mkstemp fullpath tempfile.NamedTemporaryFile
 
    .. versionchanged:: 3.8

Lib/tempfile.py

@@ -532,6 +532,10 @@ def NamedTemporaryFile(mode='w+b', buffering=-1, encoding=None,
     Returns an object with a file-like interface; the name of the file
     is accessible as its 'name' attribute.  The file will be automatically
     deleted when it is closed unless the 'delete' argument is set to False.
+
+    On POSIX, NamedTemporaryFiles cannot be automatically deleted if
+    the creating process is terminated abruptly with a SIGKILL signal.
+    Windows can delete the file even in this case.
     """
 
     prefix, suffix, dir, output_type = _sanitize_params(prefix, suffix, dir)

Misc/NEWS.d/next/Library/2021-05-17-21-05-06.bpo-4928.Ot2yjO.rst

@@ -0,0 +1 @@
+Documented existing behavior on POSIX: NamedTemporaryFiles are not deleted when creating process is killed with SIGKILL