calendarserver_purge_principals(8) on Linux
The text c9a4c960fc39, as Debian 10 (Buster) shipped it. The page shows this text now.
Calendar Server deprovisioned user clean-up utility
Flags it lists
-
--completely -
--config -
--dry-run -
--help -
--verbose -
-c -
-f -
-h -
-n -
-v