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From: erlo.haugen@gmail.com
Newsgroups: comp.lang.ada
Subject: Re: Ada.Calendar and NTP (and Unix Epoch)
Date: Tue, 24 Jul 2012 01:34:03 -0700 (PDT)
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Date: 2012-07-24T01:34:03-07:00
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> Political time is one regulated by politicians, localized, daylight saving
> etc. Political time is unusable for the purpose of time stamping and clock
> synchronization, but of course indispensable for the UI.
> 
> Ada.Calendar implicitly represents such a time. NTP, I only guess, because
> we are using other mechanisms of time distribution and synchronization, is
> not a political time. Is it UTC?
> 
> Which is why I second to Adam asking what are going to achieve.
> 
> -- 
> Regards,
> Dmitry A. Kazakov
> http://www.dmitry-kazakov.de

I see. NTP is just the number of seconds (and fractions thereof) from 1-1-1900 0:00, adjusted with leap seconds - so it is not adjusted for timezones, daylight saving. It is not UTC, as UTC does not take leap seconds in account.

The purpose of this exercise is to compare two timestamps, one base on Unix epoch and one based on NTP epoch.

Regards
Erlo