On-Rev and Daylight Savings Time (Addendum)

[Gregory Lypny]

Hi Jim,

Thanks for your thoughtful response.  I had grappled with DST in  
another project that involved press releases that were time stamp  
GMT.  It was tricky.  I like your idea of getting the seconds every  
day at midnight.  That's clever, and I think I can incorporate that  
into my site.  Sarah has a cool time conversion page on her TrozWare  
site that I am going to study as well.

Regards,

	Gregory


On Tue 1 Sep 2009, at 1:00 PM, Jim Ault wrote:

> Caution:
> You can change the time that Rev (or any program) gets on your
> computer by simply setting your computer clock to anything you like.
> The same thing can happen on any computer or server.  Just ask a large
> company that has servers in different cities and countries.
>
> The key to iRev servers is that they are probably extremely stable and
> constantly updated to one of the atomic clock sites.
> One issue of daylight savings (especially in the state of Indiana) is
> that some counties will change their clocks and others will not.
>
> Another issue is that the last daylight savings change in the Spring
> was done one week later in the UK than in the US.  The result was two
> time changes 7 days apart.
>
> A computer program running on a processor can have functions that ask
> the processor for date and time info, but daylight savings changes are
> external to the processor.
> If you write a function that gets the seconds at midnight each day,
> then see if it is 24.0 hours after the previous midnight, you know the
> processor has not changed the time zone or time shift in its control
> panel settings.
>
> If you have a local processor and one at iRev, you need to track this
> for each processor and maintain the correct offset ( +1, -1, 0 ).  You
> might want to study GMT options and use one of those.
>
> Hope this helps.
>
> Jim Ault