remote device access

[rob@plan9.att.com rob@plan9.att.com]

getting rid of the '#c' stuff is only hard because it's a widely used convention.
the notation was invented as an expedient way to address drivers before the
name space was established, a function it serves well.  it was never claimed
to be clean or elegant.  other ways may be cleaner or more elegant, but i think
	/driver/c
or some such is neither.  this is a syntactic fudge that pretends to hide the real
problem, which is that there is no name space at the dawn of time.  pretending
to have one by introducing such a notation tells a lie.  looking at it one way,
who walks these names?  if you access them by walk at all, you have a name
space and you've reduced down to a previously unsolved problem.  if you have
another access mechanism, well, you have another access mechanism and it
will not generalize.  when a mechanism doesn't generalize, i prefer the notation
to be distinct.  when what's going on is fundamentally nasty, it is polite to say
so; hence #c.

on the other hand, if one
were to attach all drivers to the name space automatically, avoiding the need for
a (public, at least) #c, building up /driver or /dev or whatever, one would go
against the grain of plan 9, where what is in the name space is what is needed
rather than all that's available.  besides, this latter form implies an attach has
been done, a semantically heavy operation best left until the driver is really
needed.