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From: jms@tardis.Tymnet.COM (Joe Smith)
Newsgroups: comp.sys.amiga.tech
Subject: Timestamps have to be UCT (was Re: 1.4 request)
Summary: Local time is ambiguous and/or nonexistant.
Message-ID: <791@tardis.Tymnet.COM>
Date: 14 Nov 89 07:38:55 GMT
References: <3824@nigel.udel.EDU>
Reply-To: jms@tardis.Tymnet.COM (Joe Smith)
Organization: McDonnell Douglas Field Service Co, San Jose CA
Lines: 24

In article <3824@nigel.udel.EDU> new@udel.edu (Darren New) writes:
>  At the file server end, the server would do an
>Examine(), use local preferences to translate the DateStamp to UTC,
>send the packet.  The client would get the packet, convert back from
>UTC to local time using the client's preferences, and all is well.
>I still think things should all be stored in local time.

This won't work.  I currently have on my floppy two files that were
created 60 minutes apart, but they both correctly say 29-Oct-89 at 1:30am.

If you have an OS that understands both GMT (UCT) and local time, there
is no way to store the correct date/time unless it is in GMT.  If you store
only local time, anything between 1:00am and 2:00am on the last Sunday
in October can be interpreted as Standard time or Daylight Savings time.
And on the first Sunday in April, any local time between 2:00am and 3:00am
will be illegal.

We want a format that stores the date/time as a monotonically increasing,
non-discontinuous value.  Local time just doesn't cut it.
-- 
Joe Smith (408)922-6220 | SMTP: JMS@F74.TYMNET.COM or jms@gemini.tymnet.com
McDonnell Douglas FSCO  | UUCP: ...!{ames,pyramid}!oliveb!tymix!tardis!jms
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