Re: [Tzdist] [tzdist] #32 (service): managing historical data

Tobias Conradi <tc@tobiasconradi.com> Fri, 24 October 2014 18:28 UTC

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Date: Fri, 24 Oct 2014 20:27:59 +0200
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From: Tobias Conradi <tc@tobiasconradi.com>
To: Paul Eggert <eggert@cs.ucla.edu>
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Cc: Time Zone Data Distribution Service <tzdist@ietf.org>
Subject: Re: [Tzdist] [tzdist] #32 (service): managing historical data
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On Fri, Oct 24, 2014 at 8:02 PM, Paul Eggert <eggert@cs.ucla.edu> wrote:
> Lester Caine wrote:
>>
>> I would probably view this as optional, EXCEPT that if one takes the
>> situation of a simple device which is also creating a log of it's data
>> now correctly using UTC timestamps,
what is "now correctly"?

>>  it also needs to log any change in
>> version of data set used while creating that log.
>
>
> That's not needed in the simple devices that I help maintain.  They log UTC.
>
> If devices need to put local time into a log for some reason, then they can
> log the UTC offset.  That is simpler and more reliable than logging the tz
> version number would be.
Why is that more reliable? Can there be different offsets for one
version of a collection of time zone data? Since you are the
maintainer of the IANA time zone database, could it be that you only
talk about the IANA TZDB and such behaviour is a specificity of the
IANA time zone database?

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Tobias Conradi
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