Re: Daylight savings time

On Mon, 16 Sep 2002, Dare wrote:

> Ok!  I think we have 2 proponents for the manual process while others watch
> the thread, one can only assume that they favor one or the other.  My
> thinking revolves around the following:
>
> 1.    How is this done on other application server platforms like HP, Sun
> and the like where Unix of different flavors are used as the OS?

FreeBSD schedules a batch job in the crontab (similar to doing a
ADDJOBSCDE) which checks if the time zone needs to be updated, and if so
it will update it.

If you found that behavior undesirable, all you'd have to do is remove
that entry from the crontab, so it wouldn't check for daylight savings
time starting/ending, and therefore would not make any changes.

> 2.    Are there "daylight saving" problems on other servers that are not
> OS400 based or do they manually change it?

None of my non-OS/400 servers needs changing manually anymore.  OS/400 is
the only one -- and because of this, I sometimes forget to do it, causing
times to be wrong for people.

> 3.    Thinking "out of the box", I will expect that the guys that work with
> the internal code will take into consideration the issues with time overlap,
> time calculations,
>        and others issues that might cause problem on the iSeries.

Okay, but there's only so much they can do.   Programs that expect time
to go forwards, never backwards, will have problems if the time changes
during their run.   There's really very little that the "internals" people
can do about that.

IMHO, people should design their programs better.  Especially if they
expect it to run at 2:00.    All they have to do is use GMT times, or
at least check the QUTCOFFSET sysval when reading the clock.  If your
software takes QUTCOFFET into account, there shouldn't be a problem.

But, the nice thing about having a scheduled job, the way FreeBSD does it,
is that you can change it's schedule to not conflict with batch jobs if
you're concerned about it.

The way Windows does it isn't very good.  But that's not unsusual for
Windows.