Perhaps using MAKEDEV ?
as in sh MAKEDEV console

I've moved MAKEDEV to sbin (it's a boot-critical system "binary").

I'm also not using -current or too close to it.

Neil Booth <neil@daikokuya.co.uk> wrote:
>So I'm playing around on a Soekris net4801 box, and decide
>I want to be able to mount / read-only, so I removed /dev/console
>so that init automatically does a MAKEDEV on an mfs filesystem.
>
>However, I want to revert this temporarily, but have not found
>a way of doing so: /bin/sh as init fails, probably because of
>lack of /dev/console, and if I use normal /sbin/init I can't
>umount /dev even in single user mode because of "device busy".
>Similarly trying to mount /dev/wd0a, my root device, simultaneously
>elsewhere gets "device busy".
>
>How can I recreate /dev/console on the /dev/wd0a filesystem and thus
>prevent an mfs /dev?
>
>Neil.