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To: Julian Elischer <julian@whistle.com>
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From: "Louis A. Mamakos" <louie@TransSys.COM>
Subject: Re: Network interfaces: removal of. 
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> does anyone have any ideas on this?

One idea:  add a new message for the routing socket which can notify
routing daemons that you want to delete an interface (or, like it or not,
it's gone now).  Hopefully they can then arrange to have active references
to the interface be removed.

I recall another system which had a the ability to "delete" a network
interface.  What it really did was cheat:  it essentially overwrote the
interface name, and shoved the data structure off into a corner.  It was
still around, though, so that if there was some errant reference to it,
nothing "bad" would happen.

Clearly, this is just a hack.  However, it seems to work "well enough",
so from a pragmatic perspective, you can't dismiss it completely.

While I'm sure that the modules that reference interfaces are finite, 
there's nothing to allocate references to them.  This would require a
level of discipline unknown to the BSD net code.  Hell, you might just
as well wish for locks on the data structures to make the code SMP safe :-)

louie