On Tue, Mar 28, 2017 at 7:28 AM, Rob Berendt <rob@xxxxxxxxx> wrote:
11:16 - 4 hours = 7:16. Remember an odd number minus an even number is an
odd number.
No need for snark.
If you were still on Eastern Standard Time then, yes, your UTC offset is
-5. However, I'm in Indiana and I thought we were the last hold outs and
we started observing daylight savings time a few years back.
Most of Arizona still doesn't observe DST. And Hawaii, but of course
their circumstances are very different from the continental U.S.
Now, don't compare to Windows as that isn't really an operating system.
No need for snark. I mean, really, that's actually just incorrect,
except for very, very narrow definitions of "operating system".
They will report the UTC as -5 but they leave it up to you to know whether
or not you're currently observing daylight savings time.
No, Windows doesn't leave it up to you to know whether you are
observing DST. What they do leave up to you is knowing what your time
zone is. (Maybe someday it will be the OS's job to have GPS, in which
case it should know its own time zone. But IBM i doesn't do it either,
and we're not calling IBM i a "fake" operating system, are we?) Note
that Windows lists Arizona as a different time zone than Mountain
Time, precisely because Arizona doesn't observe DST while (the rest
of) MT does.
Windows also does leave up to you (if you select a time zone that
observes DST) whether you want the system to automatically adjust the
clock for DST. Why it is your choice is because you might have
software that handles its own clock changes, and would be screwed up
if the system clock were to change.
The only "sin" committed by Windows is using the UTC offset during
"standard" (i.e. non-Daylight) time as a fixed component of the time
zone name *for sorting purposes*. That is, they list it next to the
verbal name so that you can look up your time zone more sensibly and
reliably.
Does putting "UTC" in the name kind of confuse things? Sure. It's the
same as using your SSN as an ID number for anything other than Social
Security purposes. But take a look at IBM's own "time zone":
QN0500EST3 in the example you cited above. The 0500 is right in the
name, just as 0600 is IBM's name for Central, 0700 is in IBM's name
for Mountain, and 0800 is in IBM's name for Pacific. IBM had the
"courtesy" of not including the letters "UTC" in the name, but that is
just as likely due to limited character space as any desire not to be
confusing.
John Y.
midrange.com
