Subject: Re: TTY virtualization driver
To: NetBSD Kernel Technical Discussion List <>
From: None <>
List: tech-kern
Date: 01/24/2002 08:41:35
> OK, let's pretend we have "foo", "bar", and "bit" boards, each of which
> provide some multiple number of tty ports, and several of each might be
> installed in our theoretical machine.
> 	foo* at pci?
> 	bar* at pci?
> 	bit* at pci?
> Traditionally we would then have three major numbers assigned to these

yes. this is natural, normal and simplest to have

/dev/ttyF00 - port 0 on foo0
/dev/ttyF13 - port 1 on foo1
/dev/ttyB29 - port 9 on bar2


you should just hardwire the interfaces like that

foo0 at pci0 dev 5 function 0
foo1 at pci0 dev 7 function 0
bar0 at pci1 dev 4 function 0


> allocation and assignment algorithms have to know every possible value
> of 'X', etc., etc., etc.  Depending on what you use ttys for, how
> flexible the software you use with them is, how many you have, how often
> you might have to change or add boards, etc., this may or may not be an
> issue for you.

tty allocation?
where you allocate tty dynamically (tty not pty)?

if you use ttys for terminals you write every tty name in /etc/ttys

> I personally think there's more benefit to doing this kind of name
> mapping in ttys, network interfaces (at least per physical layer type),


it would be almost linux.

is it EASIER to think "i connected to my second cyclades card port 17 new
modem, so hmm... first cyclades was between 65 and 96, second... oo i must
look in kernel config... oooh 128, +17 it will be /dev/tty145..."?

for me it's easier "i connected to my second cyclades card port 17, so i
need to use /dev/ttyZ1017"

for most of us i think too.