Subject: Re: TTY virtualization driver
To: NetBSD Kernel Technical Discussion List <tech-kern@NetBSD.ORG>
From: Greg A. Woods <woods@weird.com>
List: tech-kern
Date: 01/24/2002 20:15:28
[ On Thursday, January 24, 2002 at 13:51:58 (-0800), Bill Studenmund wrote: ]
> Subject: Re: TTY virtualization driver
>
> Well, it does matter if you care where the tty goes. To physically map
> where a serial line goes, you have to know what plug it goes to, and what
> device node that's hooked to.

It sure does matter what major number maps to tty devices if I pull one
dead 8-port serial board and plug in another only to find that I have to
use a different set of /dev names just to access the same 8 serial
devices.

With a common TTY driver for user-land to communicate with, and assuming
the low-level drivers have been implemented correctly so that they
attach the ports in the same order as the physical connectors are
numbered, then nothing important will change when I pull a BOCA 8-port
board and plug in the Cyclades Z-series board and swap the connected
cables over (so long as I take care not to scramble their ordering).

-- 
								Greg A. Woods

+1 416 218-0098;  <gwoods@acm.org>;  <g.a.woods@ieee.org>;  <woods@robohack.ca>
Planix, Inc. <woods@planix.com>; VE3TCP; Secrets of the Weird <woods@weird.com>