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Date: Tue, 4 Nov 1997 23:42:43 -0700 (MST)
From: Charles Mott <cmott@srv.net>
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To: Alex <garbanzo@hooked.net>
cc: Mike Smith <mike@smith.net.au>, hackers@hub.freebsd.org
Subject: Re: gettimeofday() overhead 
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On Tue, 4 Nov 1997, Alex wrote:
> On Tue, 4 Nov 1997, Mike Smith wrote:
> 
> > Unfortunately, this requires access to /dev/kmem, and thus your process 
> > must be running as root.  IMHO this isn't really an acceptable tradeoff 
> > unless the application already requires it.
> 
> Naw, just setgid kmem.
>  
> > OTOH, if +/- 1 second is good enough, a once-a-second timer and a local 
> > call to gettimeofday() would be a simple and straightforward technique, 
> > as was also suggested.
> 
> Probably right, but more accuracy within reason can't hurt.
> 

At this point, accessing the kernel time variable from user space is
mainly a point of interest (this is the hackers group, right?).  I can
read up on how to access /dev/kmem, but how is the kernel symbol table
accessed?

  -- Charles Mott