This is meant to mirror sudo's -k/--reset-timestamp and
-K/--remove-timestamp options, which revoke the temporary authorization
provided by the timestamp files in /var/run/sudo/ts.
To achieve the same effect in run0, we ask polkit to revoke our
temporary authorization. If used with a command, run0 will revoke the
temporary auth and then immediately authorize the user again, just like
sudo -k. All the bus calls are completed synchronously, as they need to
complete before authorizing the user anyway.
Like sudo, the effect of -k/--reset-timestamp is to revoke only the
tmpauthz that polkit would have used to authorize the command, if
available. The -K/--remove-timestamp option will revoke all temporary
authorizations across all ttys.
--empower gives full privileges to a non-root user. Currently this
includes all capabilities but we leave the option open to add more
privileges via this option in the future.
Why is this useful? When running privileged development or debugging
commands from your home directory (think bpftrace, strace and such),
you want any files written by these tools to be owned by your current
user, and not by the root user. run0 --empower will allow you to run
all privileged operations (assuming the tools check for capabilities
and not UIDs), while any files written by the tools will still be owned
by the current user.