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Date: Mon, 21 Jun 2004 16:31:57 -0700
From: David Schultz <das@FreeBSD.ORG>
To: David Malone <dwmalone@maths.tcd.ie>
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Subject: Re: /bin/ls sorting bug?
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On Mon, Jun 21, 2004, David Malone wrote:
> > Sorting on nanoseconds too is likely to be more confusing than
> > useful.  Even if we use one of the precious few option letters ls
> > doesn't use already to add a nanosecond display, most people won't
> > know about it because they don't care about nanoseconds.  They
> > might care when they notice---as you did---that the sort order
> > isn't what they expected.
> 
> At the moment in FreeBSD the nanoseconds field is always zero,
> unless you twiddle vfs.timestamp_precision, so it would make no
> difference to joe user. For people that do set vfs.timestamp_precision,
> it would be nice if ls did the right thing (for example, test already
> compares the nanoseconds field, after someone submitted a PR because
> it didn't).
> 
> > Is the point of sorting on nanoseconds to totally order the files
> > based on modification time?
> 
> Depending on the clock resolution (which is partially determined
> by vfs.timestamp_precision and partially determined by the actual
> clock resolution), it may not be enough to totally order the files.

Yep, that was going to be my next point.  I don't think this is
particularly useful, or necessarily even a good idea, but AFAIK
POSIX doesn't say anything about using a consistent timer
resolution when processing file timestamps, so don't let that stop
you...

Now let's re-raise the *original* bikeshed of adding nanosecond
support to sleep!