Subject: Re: Executing jobs at DST start/end
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Andrew Brown <atatat@atatdot.net>
List: tech-userlevel
Date: 04/18/2003 22:03:57
>> change it to the more generic description
>>     "please run this job whenever local time shifts due to tz data"
>> and you've got something.  think "local sidereal time".
>
>Heh.  Run on local solar time and your job will be constantly running.

...while on a concorde?  no...they're not flying.  you'll have to buy
a surplus sr-71 from lockheed.

>> keep in mind that you'll also have to keep local state in as atomic a
>> fashion as possible, since you can't guarantee that the machine will
>> be running when time shifts.
>
>Which is another point: do you _want_ it to get run if the machine was
>down when the UTC offset shifted?  I can see arguments either way.

well...if the correct local adjustment hasn't been made, yes.

>What if it's been down long enough that it's shifted back?  What if
>multiple shifts have occurred but it's now not what it was last run?

that's why i noted that keeping local state independently was
important.  if you're going to play this game, you need to know what
cards you've already played.

>The devil is in the details.

and now you speak of him.  :)

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