> The Right Way(tm) to do this is to make the parallel port an abstract
> device, which can have either:
> 
> 	- a tty (for use as a printer port)
> 	- a plip layer
> 	- a ZIP drive
> 
> ...or whatever attached as a child.

I'm not sure that I agree with that.

That might make sense for some types of devices (e.g. the MI z8530
driver), where the types of hardware attached are pretty well nailed
down (e.g. the sun3's tty ports, keyboard, and mouse ports).

However, on a parallel port, typically:

	(1) it's very easy to use the port for something else
	    (i.e. yank the plip cable, plug in the ZIP drive),
	    and doing that is common, and

	(2) it's not clear that it's possible to tell what's at
	    the other end of the cable.

In my opinion, a line discipline-line mechanism would probably be much
more appropriate.  ("why aren't ppp, SLIP, mice, etc., configured as
devices on serial ports?")




cgd