On Mon, 03 May 2021 09:30:46 +0100 Ralph Corderoy <ralph@inputplus.co.uk> sez:
Hi Bob,
Hi Ralph,
This time you're not giving me happy-useful news. B-D
$ TZ=Australia/Lord_Howe date -d '01 Aug'
2021-08-01 00:00:00 +1030 Sun
$ TZ=Australia/Lord_Howe date -d '01 Feb'
2021-02-01 00:00:00 +1100 Mon
Wat. -_-##
Why?! I can see some localities deciding that having their time zone
not be an integer number of hours offset can be more representative or
useful for them
Yes, India is +05:30 with no DST. And there are finer-grained ones,
e.g.
$ tz() { printf '%s %s\n' `TZ=$1 date +%z` $1; }
$ for t in UTC Australia/Eucla; do tz $t; done
+0000 UTC
+0845 Australia/Eucla
$
I had an inkling that it might be bad for NMH to try to handle
DST calculations on its own; hopefully it's not trying to do any
with time zones (but rather relying on system libraries that are
intended to figure out all that) ....
Perhaps some known-to-fail tests could be added to nmh's test suite.
but why mess with the DST offset, too?
In Lord Howe's case it's so its time agrees with the mainland half the
time. Aussies.
More like "Humans." B-)
Why bother with DST in the first place? Isn't it a relic of the
pre-industrial era when farm labourers would rise by the sun to maximise
work on the land?
Nope: it's a relic of the Industrial Age/WW1:
https://en.wikipedia.org/wiki/Daylight_saving_time
I didn't bother adjusting one year, initially by accident, and given
work was a bit flexible on hours it was quite simple to just adjust ‘my
truth’ of time to local time for the odd appointment, TV programme
schedule, etc. Isn't the sudden switch for those that must live by the
state's clock meant to harm health?
There are indications that, at least on the Monday after each
switchover, certain problems see spikes, such as car crashes and
heart attacks. I personally wouldn't mind seeing DST eliminated.
At this rate, they might as well just create a server that calculates
the sun's position in the sky on a second-by-second basis and send out
that time accordingly for people to sync their computers to. -_-#
That occurred to me on the last switch and Google suggested its been
done by others. Though I think it might be better to produce a local
time so my normal waking clock times are centred around the daylight.
:-)
Well, that's what I meant: depending on your longitude, the
server would give you a "local time," perhaps centered around the
daylight. Though I also heard one proposal for just a universal
time (like UTC) that everyone uses (to avoid issues like "Is my
3pm your 10am or 11am?"), and you always do a conversion to
calculate your local time. Both of these seem to require
computing devices, making it hard or impossible for us old fogeys
who still use _actual_ clocks. B-)
DST is generally odd. The Yanks mostly have DST. But not in Arizona.
Except for Navajo Nation which is inside AZ. But there's no DST in Hopi
Nation which is inside Navajo Nation.
$ tz() { printf '%s %s\n' "`TZ=$1 date '+%z %Z'`" $1; }
$ for t in America/{Phoenix,Shiprock}; do tz $t; done
-0700 MST America/Phoenix
-0600 MDT America/Shiprock
$
And if you carry on up the Wakhjir Pass in Afghanistan then the clocks
will switch from +0430 to +0800 as you enter the People's Most
Democratic Uncensorious Republic of China.
Like I said: "Humans." B-)
Bob