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From: Don Yuniskis <dgy@rtd.com>
Message-Id: <199701260938.CAA07377@seagull.rtd.com>
Subject: Re: suggestion for kernel printk() ?
To: bde@zeta.org.au (Bruce Evans)
Date: Sun, 26 Jan 1997 02:38:37 -0700 (MST)
Cc: bde@zeta.org.au, dgy@rtd.com, freebsd-hackers@freefall.freebsd.org
In-Reply-To: <199701260856.TAA23790@godzilla.zeta.org.au> from "Bruce Evans" at Jan 26, 97 07:56:20 pm
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> >> probing all the devices.  printf() doesn't have any flow control.  It
> >> can't afford to pause once the system is up because that would freeze
> >> the whole system.  Freezing for 1 msec per character to for output at
> >> 9600 bps is bad enough.
> >
> >But would it actually *break* anything?  Perhaps I'll hack in a two line
> >patch next time I rebuild a kernel and see what happens...
> 
> Yes, it would steal characters from the foreground console unless the
> keyboard is dedicated to low-level console input.

I guess a single character pushback isn't supported at that level?
--don