From 081187f169556fb1b2d6a9b96f7b7e509f6ad985 Mon Sep 17 00:00:00 2001 From: "Miss Islington (bot)" <31488909+miss-islington@users.noreply.github.com> Date: Fri, 22 May 2026 23:17:51 +0200 Subject: [PATCH] [3.15] gh-82907: Document mtime=0 for reproducible tarfile gzip output (GH-150269) (GH-150271) (cherry picked from commit 9df2b6ccc719b0bc0167da65b72b57f9da39398b) Co-authored-by: Omkar Kabde --- Doc/library/tarfile.rst | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Doc/library/tarfile.rst b/Doc/library/tarfile.rst index 6f1e01cf5aa6..9b9783d8e580 100644 --- a/Doc/library/tarfile.rst +++ b/Doc/library/tarfile.rst @@ -144,7 +144,9 @@ Some facts and figures: For modes ``'w:gz'`` and ``'w|gz'``, :func:`tarfile.open` accepts the keyword argument *mtime* to create a gzip archive header with that mtime. By - default, the mtime is set to the time of creation of the archive. + default, the mtime is set to the time of creation of the archive. Use + *mtime* ``0`` to generate a compressed stream that does not depend on + creation time, for reproducible output. For special purposes, there is a second format for *mode*: ``'filemode|[compression]'``. :func:`tarfile.open` will return a :class:`TarFile` -- 2.47.3