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Re: mjf-devfs2 branch

>> [...], what about other things, such as mv, ln, ln -s, and objects
>> other than device files in /dev?
> Well, I happened to leave out mv from the above point, but it was
> supposed to be included, as a mv action just specifies a new filename
> to be applied for a device node.

Yes, I would expect mv to be simple. :)

> I hadn't thought about ln, but I guess it's like specifying another
> filename for that device node.

Yes, but with an important difference.  "mknod foo c x y; ln foo bar"
and "mknod foo c x y; mknod bar c x y" produce subtly different
results: in particular, consider which nodes are affected when tools
such as chmod or chown are applied to one of them.

Is this difference actually important enough in practice to be worth
implementing?  I don't know.  I have no real idea how hard it is to do;
it's also something I personally use relatively seldom - but it does
seem to me that trying to explain why it works differently in /dev from
elsewhere is something that's likely to confuse people.

> You also only need the link around when the device is actually on the
> system.

Well...maybe.  That certainly should be the default, it seems to me,
but I'm not convinced the alternative is useless.  (It may be close
enough to useless to be not worth doing, to be sure - especially in
view of the possibility of creating device nodes in the underlying /dev
and mounting devfs with -o union.)

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