Redirecting kernel messages

[Cameron Hutchison <camh+dl@xdna.net>]

I'm looking to clean up my display as my machine boots. Up until the
time init(8) starts, everything is fine. After that point, kernel
messages and init script messages become interleaved, and I find it
difficult to tell at a glance if something has gone wrong on startup
(and on the fast machines of today, a glance is all you get before X
starts :-)

So, at the beginning of the init process, I would like the kernel
messages to be redirected to another tty - preferably /dev/tty12, since
I dont use that for anything else. It would be nice if all kernel
printk after that point go to that console too (ie. not just boot up
messages, but also the regular printks that occur as the system runs).

I've tried setting CONSOLE and console on the kernel command line to
[/dev/]tty12, but that didn't work.

Is it possible to do this? Even just knowing the syscalls to do this
would be fine if there's no other way. I'll just hack init.

CHeers