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Date: Wed, 24 Apr 1996 23:38:20 -0400 (EDT)
From: Sujal Patel <smpatel@umiacs.umd.edu>
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To: Bruce Evans <bde@zeta.org.au>
cc: gpalmer@freebsd.org, current@freebsd.org
Subject: Re: request for a new "feature" as regards DDB
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On Thu, 25 Apr 1996, Bruce Evans wrote:

[ In reference to implementing a timeout in DDB to dump core and reboot]

> >Can we sit in a loop, while polling the keyboard for input?
>
> Yes, you can usefully poll the clock(s) while polling the keyboard,
> provided:
>
> a. polling is non-destructive.  This makes it difficult to use timer0,
>    timer1 and the RTC. Perhaps they can be read without (destructively)
>    latching the count.  Even that steals some state if a non-debugging

If using the timers is difficult, you could record (on boot up) the
approximate time that an inb() takes and use that figure to "approximate"
the amount of time we should wait for keyboard input.  It doesn't have to
be exactly the same for each system, just a "good amount" of time.


Sujal