Jim McGowen wrote:

> That's what I was thinking... but both the palm and the pc are set to the 
> same time zone so I don't understand why.  If this is the case then either 
> the Palm is giving me a timestamp from some other time zone or the PC is 
> interpreting the timestamp as being in some other timezone.  I don't get 
> it... a timestamp is a timestamp why would time zones even matter?

Ultimately most computers run some sort of clock and supply
functions to give you the local time or UTC (a/k/a GMT) time,
depending which you want.

The question is, does that native clock that the OS uses work
in local time or in UTC?  In which case is it converting -- when
you ask for local, or when you ask for UTC?

The other question, is the answer to the previous question the
same for Palm OS and for Windows?


To put all this another way, the documentation for Palm OS's
TimGetSeconds() says it returns "the number of seconds elapsed
from 12:00 A.M. on January 1, 1904 to the current date and time".
But is that 12:00AM, 1/1/1904 *local* time or UTC?  What about
the analogous function call on Windows?


Based on http://www.decimaltime.hynes.net/computers.html ,
it would appear that Windows keeps time relative to a certain
UTC time.  So, the next question is whether Palm OS keeps time
in UTC or not.  Based on OS 4.0 example source, it seems that
TimSecondsToDateTime() takes no account of time zones, and
I believe you get the local time if you do

        TimSecondsToDateTime (TimGetSeconds(), datetimeptr);

Therefore, it seems like TimGetSeconds() is giving you the
number of seconds since the clock struck 12:00AM on 1/1/1904
in YOUR time zone.  I don't know what function call you're
using on Windows, so I can tell whether it uses local time,
but if it isn't, you're going to have to do time zone
correction.

So, I *think* what you need to do is use the example code
in the TimTimeZoneToUTC() documentation to convert
TimGetSeconds() time to UTC.

  - Logan

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