Subject: Re: An approach for detachable interfaces.
To: Bill Sommerfeld <>
From: David Evans <>
List: tech-net
Date: 11/05/1999 16:11:58
Bill Sommerfeld wrote:
> Can you be more specific about what sort of "parameters" you're
> talking about?

  Things like IP address and things that depend on it.

> i can't see any scheme which allows for userland to
> get an event on card insertion not also get an event on card removal,

  Err...I didn't mean to imply that userland should only get one of those
events.  But clearly the setting of the new parameters can't happen until card

> Is there really a meaningful difference between
> 	ep0 with parameter set A at home
> 	ep0 with parameter set B at work.
> and 
> 	ep0 with parameter set A at home
> 	ep1 with parameter set B at work.
> if at most one card is ever inserted at any given instant?

  Potentially, yes.  If I want to DHCP for information to configure whatever
card I've just inserted then I presumably don't want to have to dance around
figuring out what the name of the new interface should be.  I suppose that
the system could say "ep1 just appeared" but I have a hunch that there may be
value in knowing that this is somehow like the ep0 that used to be around.

David Evans          (NeXTMail/MIME OK)   
Computer/Synth Junkie            
University of Waterloo         "Default is the value selected by the composer
Ontario, Canada           overridden by your command." - Roland TR-707 Manual