pu[rge]

 Purges expired local registry entries.

 This command has no options or arguments.

 The time limit, or lifespan, for which an entry in the local
 registry is valid is set as a property of the local registry
 with the properties subcommand.  When the purge subcommand is
 run, it deletes all expired entries.  The lifespan begins when
 an entry for the principal is added to the local registry (that
 is, the beginning of the lifespan is the last time the principal
 logged in to the local machine.) The lifespan ends after the time
 limit set as a local registry property.