thanks Hal :)

-----Original Message-----
From: Hal Mueller [mailto:[EMAIL PROTECTED]]
Sent: sexta-feira, 25 de Janeiro de 2002 18:07
To: Palm Developer Forum
Subject: Re: Daylight Saving


It "supports" DST in the sense of having an indication of whether DST 
is currently being observed.  But it only does so correctly from OS 
4.0 forward.  The OS does not automatically change between standard 
time and DST (nor should it!  the information required to do that 
correctly worldwide is vast, and ever-changing).

Prior to 4.0, there were prefs prefMinutesWestOfGMT and 
prefDaylightSavings.  But there was no UI/pref panel to change them, 
and I think most developers didn't use them or even known about them. 
Further, in the 3.5 and earlier PalmOS releases, prefMinutesWestOfGMT 
was actually minutes EAST (this is minutes of time, not minutes of 
arc); its value was, IIRC, documented as limited to plus/minus 720. 
Since there are time zones more than 12 hours away from UTC/GMT, this 
implementation didn't really do much.  Using it, even for devices 
where it's the only game in town, is a Bad Idea; better to roll your 
own.

 From 4.0 forward, there are preferences that work, there's a 
preference panel to set them, there are well-designed documented 
system API's to get them (see TimTimeZoneToUTC in the PalmOS 
Reference for the details, and pointers to other functions).

Anybody have the time?  It's urgent ;)


----
Hal Mueller                [EMAIL PROTECTED]
Mobile Geographics LLC     http://www.mobilegeographics.com/
Seattle, Washington        (206) 297-9575
Get CelestNav 2.2.2! http://www.mobilegeographics.com/celestnav/ 

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