> #define SARCASM
> 
> Hell, while we're at it, why don't we just rip the guts out of hier(7),
> rewrite it and make root mfs, or populate it with a bunch of symlinks
> to the real /etc, /dev, /bin and /sbin.  Never have to worry about a
> root fsck again.  With dynamic root, dev, proc, tmp, all we'd have to
> worry about is /usr.
> 
> #undef SARCASM

Actually I have been seriously liking the concept of "single-user root is mfs"
for a while now. Union-mount the "real" root disk on top of it after fsck.
The "live" kernel file used by libkvm could move down into /kern/netbsd.

For things like kernfs, procfs, devfs, etc., it means less directories have
to be maintained on root, unless you want to preserve permission changes;
for devfs it eliminates one standing objection, IIRC.

It standardizes on a method that works well for using msdosfs as root.
(Get a look at the kludge code in init(1) that uses mfs internally to
fake up a /dev when it detects that root is msdosfs.)

It also makes the natural boot process be very appropriate for embedded
systems and also mission-critical boxes, plus more code is shared between
how the install floppy works and how the normal system works.

Edwin Foo did something like this with NetBSD/arm32 for a robot controller
that is competing in the robot wars next month, and he just adapted the
install floppy stuff to do it.

Todd Whitesel
toddpw @ best.com