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From: usenet@mcdchg.UUCP
Newsgroups: comp.unix
Subject: Re: Setting accurate application timers under Unix/Xenix
Message-ID: <1896@mcdchg.UUCP>
Date: Wed, 30-Sep-87 10:53:43 EDT
Article-I.D.: mcdchg.1896
Posted: Wed Sep 30 10:53:43 1987
Date-Received: Fri, 2-Oct-87 07:11:09 EDT
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You it the nail on the head.  Write a device driver that sleeps on the
callout table for the desired number of ticks (the standard idiom is
to use the number of bytes requested in a read/write pseudo call to the
device driver).  After sleep() returns, mung on the priority as needed
to get the scheduler to run that job next.  I believe you only need to
set the priority below curpri to get yourself running again.  Also -
don't forget to sleep at a very high priority or the wakeup will take
longer.

You will want to provide some security for this device as it could be
used by impatient department heads to get their work done fast ...

- John.
---
John F. Haugh II		HECI Exploration Co. Inc.
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