hur.st's bl.aagh

mac_portacl(4) is a FreeBSD kernel security module providing an access control policy for permitting specific users and groups to bind to ports that would otherwise be restricted to the super-user.

portacl-rc is an rc script that makes configuring it easier and safer.

Wanting to hone my shell scripting skills a bit, I ended up reimplementing a cute script by Dustin Kirkland.

run-one is basically a thin wrapper around lockf(1), or on Linux flock(1):

-% lockf /var/tmp/sleep-5.lock sleep 5
# <runs sleep 5 under the named lock>
-% run-one sleep 5
# <runs sleep 5 under a lock named by a SHA256 of its arguments>