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Re: Interface description support

>> What's been getting discussed here I would call an "alias", though
>> I'd want to find a different word for it because ifconfig(8)'s
>> command line already has an "alias" keyword.
> Well, isn't "alias" an abbreviation for "inet alias"?  If so, you
> could use something like "name alias" for the new functionality.

Possibly.  It's been a long time since I looked at ifconfig's code.

>> Really, though, this whole thing is a botch.  Berkeley created a new
>> namespace for network interface names when they should have been
>> just nodes in /dev [...].  The _right_ fix, it seems to me, is to
>> move network interfaces into /dev (possibly in a subdirectory?),
>> where they should have been all along [...]
> Yes. But it's far too late to /move/ them, I guess.

Only in a political sense.  There is no technical reason that couldn't
be done.  The closest I can see is that it would be a lot of work
(because most/all of the userland things that touch network interfaces
would have to change, as would the kernel interfaces behind those

Mind you, that political sense is strong.  I don't expect that move to
be done, certainly not anytime soon.  But I still think it's the
_right_ fix.

> Couldn't that be done via a pseudo-filesystem (which you could mount
> to /dev/net) or a part of kernfs (which you could symlink to
> /dev/net) [...]

Yes, but then you have the persistence problem.  I've never liked
kernfs because it doesn't - at least in the versions I've seen - have
any sort of persistent state.  It's mostly tolerable because there's
little reason to want to use things like mv or chmod on kernfs objects,
but it's an annoying violation of the POLS that I can't, for example,
"chmod 664 /kern/hostname; chgrp foo /kern/hostname" once to let anyone
in group foo change the hostname.

If I "ln -s tty00 /dev/rain-sensor", that (a) works and (b) persists
across reboots.  We don't currently have any way to, say, let anyone in
group sniffer tcpdump -i wm0, except by making tcpdump setuid and
having it perform the permissions check manually.  It should be just
"chmod 640 /dev/wm0; chgrp sniffer /dev/wm0" (and should persist across

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