[ANN] Major Windows DST Bug

[Ken Ray]

On Mon, 12 Mar 2007 14:39:36 -0700, Jim Ault wrote:

> On 3/12/07 2:06 PM, "Ken Ray" <kray at sonsothunder.com> wrote:
> 
>> I have uncovered a Major (BLOCKER) Windows bug related to the most
>> recent change in Daylight Savings Time for the United States.
>> Revolution will overcompensate for the DST by adding and additional
>> hour to the time whenever you execute 'convert'.
> (full text below)
> 
> Yes, Ken, we have already discovered the Windows XP bug but weren't sure
> what was going on until your email.  My networking apps (9 of them) are
> clobbered.  That means our business is dead in the water until I can do a
> rewrite, but that is not a simple task for us.  Fortunately,  most of our
> computers are OSX and don't have to be fixed... at this time.
> 
> For us, timing is critical to-the-second, so I am going to build a
> time-stamp-message system so we don't have to rely on a Rev function, or one
> of the operating systems/platforms in any of the countries we operate.
> 
> Very expensive so far, since the core engine has to run on WinXP.  Looks
> like a compatibility switch needs to be added to apps to test DST+WinXP+
> greater than 2006+(?)+(?).  And what about virtual machines?  Does XP
> running in Parallels send the "2:05" rather than "3:05"?

I would assume it would have the same problem since it is virtualized 
to the processor, so the OS is really Windows (even though it's on a 
Mac). Sarah Reichelt posted a fix that can be used in the meantime - 
apparently the cue is that if the "hour" slot in a dateItems conversion 
is "3" instead of "2", you subtract 3600 from the seconds (an hour) and 
then run a normal convert to get the right time.

It's still a systemic problem to fixed IMHO, however, no matter what 
workarounds we might come up with.


Ken Ray
Sons of Thunder Software, Inc.
Email: kray at sonsothunder.com
Web Site: http://www.sonsothunder.com/