On Tue, 26 Sep 100 dribbling@thekeyboard.com wrote:

> Excellent, thanks Bill! So presumably the shell doesn't
> know or care that it's running on a virtual console?
> 
	Yes - you can also have virtual terminals completely in
	userland - using the misc/screen package from pkgsrc.

> Here's another question that I'm wondering about: I'm
> assuming that I need at least one console (either virtual or
> physical) and that the console subsystem will need to keep
> some status information for each console.  Presumably then,
> the more virtual consoles I have the more memory is used for
> them.  If they share common code, the first console will use
> more memory than each additional console.  Am I barking up
> the right tree here?
> 
	That seems reasonable. 

> I suppose the next step would be to look at the console
> subsystem source code (if I can find it, and make head or
> tail of it).
> 
	wscons(4) is a good place to start for a (somewhat sketchy)
	overview.

> I was talking to some friends about TTL mono monitors and
> their associated display adaptors.  I liked MDA, probably
> because its simplicity appealed to me (4Kb ought to be
> enough display RAM for everybody! ;o) I know someone who has
> been asking about using a Hercules card under NetBSD.  I
> imagine its MDA emulation could be used to provide a single
> console, but can't help wondering whether its extra RAM
> might be used to provide a few virtual consoles. Is there an
> easy way to find out whether anyone has looked at this
> possibility?

	It would be perfectly feasible to adapt wscons to allow
	virtual terminals on MDA as well as VGA hardware - IIRC you do
	not need any extra memory on the card - the contents of the
	extra terminals are stored in kernel memory and copied across
	when the active console is switched.

	If you have the card, start on the code :)

                David/absolute
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