From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Sun, 13 Sep 2009 15:41:05 -0500
From: "Marc A. Criley" <mcNOSPAM@mckae.com>
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Subject: Re: Dates and Times in GNAT on Linux
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Date: 2009-09-13T15:41:05-05:00
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Jeffrey R. Carter wrote:
> Marc A. Criley wrote:
>>
>> I can then get the start of the Unix/UTC epoch via:
>>    UTC_Epoch_Start := Calendar.Time_Of(1970, 1, 1)
>>                         + Duration(Calendar.Time_Zones.UTC_Offset * 60);
>>    -- For where I live, right now the UTC_Offset is -300 minutes,
>>    -- i.e. -5 hours.
> 
> This is your problem. The offset on 1970 Jan 01 00:00:00.00 was -6 hrs.

Yep. I'm retrieving the UTC_Offset in effect today (which is the default 
value of the UTC_Offset argument), not what it was at that date/time.

Thanks! I knew I was missing something basic here.

> Of course, any attempt to relate an Ada.Real_Time.Time to an 
> Ada.Calendar.Time is completely compiler dependent, is unlikely to work 
> with any other compiler, and could stop working with a different version 
> of the same compiler.

Yep. But that's an issue I can deal with here.

Marc