From systemd-198/NEWS: * tmpfiles gained a new "X" line type, that allows configuration of files and directories (with wildcards) that shall be excluded from automatic cleanup ("aging").
How is this different from the "x" (lower case) line type?
I think that 'x' excludes the directory and its contents, while 'X' only the directory (contents can be still cleaned up).
This has been added in commit 274d6ee and will be part of OpenRc 0.12. We currently do not have the cleanup function implemented in OpenRc, so this is just a dummy function that does nothing. Thanks for the report.