Similar to systemd's RemainAfterExit=yes. Prevents the task from
re-running on runlevel re-entry and ensures the post: script runs
when explicitly stopped or when leaving valid runlevels.
Useful for tasks that set up persistent state like firewall rules:
task [2345] remain:yes \
post:/usr/sbin/teardown-firewall \
/usr/sbin/setup-firewall -- Firewall setup
Not supported for bootstrap-only tasks (runlevel S only) since these
are deleted immediately after completion.
Implement Linux capability support for services, allowing them to run
with minimal required privileges instead of running as root. This uses
the modern IAB (Inheritable, Ambient, Bounding) API from libcap.