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Date: Tue, 1 Apr 1997 15:19:47 +0100
From: Josef Karthauser <joe@pavilion.net>
To: gbeach@cybernet.com
Cc: hackers@FreeBSD.ORG
Subject: Re: Internal clock
References: <3340C326.6150@cybernet.com>
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In-Reply-To: <3340C326.6150@cybernet.com>; from Glenn Beach on Tue, Apr 01, 1997 at 09:11:18AM +0100
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On Tue, Apr 01, 1997 at 09:11:18AM +0100, Glenn Beach wrote:
> I have been searching for an answer to the following question.  Doug
> White at questions@freebsd.org said that you may be able to help.  So
> here it goes:
> 
> How can I make time measurements in increments smaller than the clock
> tick?  Specifically, I am running BSD on a Pentium PC which has 128
> clock ticks per second.  Is there any way to improve the resolution?
> 

I'm using gettimeofday which returns:

     struct timeval {
             long    tv_sec;         /* seconds since Jan. 1, 1970 */
             long    tv_usec;        /* and microseconds */
     };

I've no idea of the actual system resolution, but I assume (without
checking the source code) that the kernel will provide the best
resolution available to the system.

BTW a question to the hackers... does anyone have any plans for
adding a real-time scheduling class, aka threads under solaris?
I'm writing some midi software and could really do with a real-time
class thread to handle the timing subsystem.

Joe
-- 
Josef Karthauser        
Technical Manager       Email: joe@pavilion.net
Pavilion Internet plc.  [Tel: +44 1273 607072  Fax: +44 1273 607073]