From a1a7f079f21c02fd4e19824f66e2b1ebb75a73dc Mon Sep 17 00:00:00 2001
From: markm <markm@FreeBSD.org>
Date: Tue, 25 Jul 2000 21:22:17 +0000
Subject: [PATCH] Forgot from last commit:

o if the device is being written to, and the user is not root, or
  the securelevel is greater than 0, then fail with EPERM.