From dbc3cc8b832a7648f68b69e1322563d64cffd9c4 Mon Sep 17 00:00:00 2001 From: Daan De Meyer Date: Tue, 20 Jun 2023 12:59:24 +0200 Subject: [PATCH] tmpfiles: Add note to man page about guaranteed cleanup for files/directories --- man/tmpfiles.d.xml | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/man/tmpfiles.d.xml b/man/tmpfiles.d.xml index ef0bb1f7f89..495315d55c6 100644 --- a/man/tmpfiles.d.xml +++ b/man/tmpfiles.d.xml @@ -661,6 +661,14 @@ d /tmp/foo/bar - - - bmA:1h - Applications may use this to temporarily exclude certain directory subtrees from the aging algorithm: the applications can take a BSD file lock themselves, and as long as they keep it aging of the directory/file and everything below it is disabled. + + This behavior can be used to ensure guaranteed cleanup of files or directories whose lifetime + should be aligned with the process that created them by having that process create them in a location + monitored by systemd-tmpfiles with an age of 0, and having the + process immediately lock the directory or file before using it. Because the BSD lock is process + specific, the file is guaranteed to be unlocked as soon as the process exits, meaning that even if the + process crashes, those files and directories will be unlocked and cleaned up by + systemd-tmpfiles. -- 2.47.3