A new method for catching a "break" signal was added in -current.

man cnmagic

On Thu, 3 Jan 2002, Simon J. Gerraty wrote:

> Date: Thu, 3 Jan 2002 02:52:16 -0800 (PST)
> From: Simon J. Gerraty <sjg@crufty.net>
> To: port-sparc@netbsd.org
> Cc: sjg@crufty.net
> Subject: BREAK on console ignored
>
> I'm not exactly sure when this stopped working...
>
> # uname -a
> NetBSD too.crufty.net 1.5ZA NetBSD 1.5ZA (TOO) #0: Tue Jan  1 03:00:52 PST 2002     root@too.crufty.net:/l0/sys/compile/TOO sparc
>
> This is an SS20 with serial console.
>
> During initialization, BREAK drops me to the prom's ok prompt.
>
> Once the kernel has started booting though, BREAK is ignored.
> My normal kernel does not have either of DDB or KGDB defined.
> From dmesg.boot:
>
> zstty0 at zs0 channel 0 (console i/o)
>
> suggests that zs is being used for the console.  Here I see zs_abort()
> which looks like it should end up calling prom_abort, but I don't see
> where zs_abort is hooked in.
>
> If I'm off track, a pointer would be appreciated.
>
> Thanks
> --sjg
>
>

Elfin