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From: Kirk McKusick <mckusick@mckusick.com>
To: John Baldwin <jhb@freebsd.org>
Subject: Re: futimens and utimensat vs birthtime
cc: Adrian Chadd <adrian.chadd@gmail.com>,
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 Jilles Tjoelker <jilles@stack.nl>
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> From: John Baldwin <jhb@freebsd.org>
> To: Adrian Chadd <adrian.chadd@gmail.com>
> Subject: Re: futimens and utimensat vs birthtime
> Date: Mon, 17 Aug 2015 15:28:45 -0700
> 
> On Sunday, August 16, 2015 12:05:07 PM Adrian Chadd wrote:
>> .. then make it take a struct and a type flag. :P
>> 
>> Then you can extend it however you'd like.
> 
> I think that might be a bit much (making it a struct), but one option
> could be to add an argument that says how many timespecs are in the
> array.  Any "missing" timespecs could be treated as if they were set
> to UTIME_OMIT.  This would in theory mean you could support additional
> timestamps in the future without needing new calls.  I'm just not sure
> if there are any conceivable timestamps such that this flexibility is
> warranted?

I agree that it is unlikely that you would ever need another timestamp.
But just to stretch my imagination to think of a conceivable one, how
about a "snapshot" timestamp that indicates the time that the snapshot
of the file was taken. If it is a log file, that would let you know when
events stopped being able to be logged to it.

	~Kirk