* [9fans] time zones
@ 2011-03-27 22:35 Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-28 2:04 ` erik quanstrom
0 siblings, 1 reply; 11+ messages in thread
From: Lyndon Nerenberg (VE6BBM/VE7TFX) @ 2011-03-27 22:35 UTC (permalink / raw)
Even stranger, newfie time is not making sense. The Newf's have
been half an hour off the rest of the world for ages. Yet:
lyndon at frodo% cat Canada_Newfoundland | tzdump
NST NDT
Sun Apr 26 02:00:00 GMT 1970 Sun Oct 25 01:00:00 GMT 1970
Sun Apr 25 02:00:00 GMT 1971 Sun Oct 31 01:00:00 GMT 1971
Sun Apr 30 02:00:00 GMT 1972 Sun Oct 29 01:00:00 GMT 1972
Sun Apr 29 02:00:00 GMT 1973 Sun Oct 28 01:00:00 GMT 1973
Sun Apr 28 02:00:00 GMT 1974 Sun Oct 27 01:00:00 GMT 1974
Sun Apr 27 02:00:00 GMT 1975 Sun Oct 26 01:00:00 GMT 1975
Sun Apr 25 02:00:00 GMT 1976 Sun Oct 31 01:00:00 GMT 1976
Sun Apr 24 02:00:00 GMT 1977 Sun Oct 30 01:00:00 GMT 1977
Sun Apr 30 02:00:00 GMT 1978 Sun Oct 29 01:00:00 GMT 1978
Sun Apr 29 02:00:00 GMT 1979 Sun Oct 28 01:00:00 GMT 1979
Sun Apr 27 02:00:00 GMT 1980 Sun Oct 26 01:00:00 GMT 1980
Sun Apr 26 02:00:00 GMT 1981 Sun Oct 25 01:00:00 GMT 1981
Sun Apr 25 02:00:00 GMT 1982 Sun Oct 31 01:00:00 GMT 1982
Sun Apr 24 02:00:00 GMT 1983 Sun Oct 30 01:00:00 GMT 1983
Sun Apr 29 02:00:00 GMT 1984 Sun Oct 28 01:00:00 GMT 1984
Sun Apr 28 02:00:00 GMT 1985 Sun Oct 27 01:00:00 GMT 1985
Sun Apr 27 02:00:00 GMT 1986 Sun Oct 26 01:00:00 GMT 1986
Sun Apr 5 02:00:00 GMT 1987 Sun Oct 25 01:00:00 GMT 1987
Sun Apr 3 02:00:00 GMT 1988 Sun Oct 30 01:00:00 GMT 1988
Sun Apr 2 02:00:00 GMT 1989 Sun Oct 29 01:00:00 GMT 1989
Sun Apr 1 02:00:00 GMT 1990 Sun Oct 28 01:00:00 GMT 1990
Sun Apr 7 02:00:00 GMT 1991 Sun Oct 27 01:00:00 GMT 1991
Sun Apr 5 02:00:00 GMT 1992 Sun Oct 25 01:00:00 GMT 1992
Sun Apr 4 02:00:00 GMT 1993 Sun Oct 31 01:00:00 GMT 1993
Sun Apr 3 02:00:00 GMT 1994 Sun Oct 30 01:00:00 GMT 1994
Sun Apr 2 02:00:00 GMT 1995 Sun Oct 29 01:00:00 GMT 1995
Sun Apr 7 02:00:00 GMT 1996 Sun Oct 27 01:00:00 GMT 1996
Sun Apr 6 02:00:00 GMT 1997 Sun Oct 26 01:00:00 GMT 1997
Sun Apr 5 02:00:00 GMT 1998 Sun Oct 25 01:00:00 GMT 1998
Sun Apr 4 02:00:00 GMT 1999 Sun Oct 31 01:00:00 GMT 1999
Sun Apr 2 02:00:00 GMT 2000 Sun Oct 29 01:00:00 GMT 2000
Sun Apr 1 02:00:00 GMT 2001 Sun Oct 28 01:00:00 GMT 2001
Sun Apr 7 02:00:00 GMT 2002 Sun Oct 27 01:00:00 GMT 2002
Sun Apr 6 02:00:00 GMT 2003 Sun Oct 26 01:00:00 GMT 2003
Sun Apr 4 02:00:00 GMT 2004 Sun Oct 31 01:00:00 GMT 2004
Sun Apr 3 02:00:00 GMT 2005 Sun Oct 30 01:00:00 GMT 2005
Sun Apr 2 02:00:00 GMT 2006 Sun Oct 29 01:00:00 GMT 2006
Sun Mar 11 02:00:00 GMT 2007 Sun Nov 4 01:00:00 GMT 2007
Sun Mar 9 02:00:00 GMT 2008 Sun Nov 2 01:00:00 GMT 2008
Sun Mar 8 02:00:00 GMT 2009 Sun Nov 1 01:00:00 GMT 2009
Sun Mar 14 02:00:00 GMT 2010 Sun Nov 7 01:00:00 GMT 2010
Sun Mar 13 02:00:00 GMT 2011 Sun Nov 6 01:00:00 GMT 2011
Sun Mar 11 02:00:00 GMT 2012 Sun Nov 4 01:00:00 GMT 2012
Sun Mar 10 02:00:00 GMT 2013 Sun Nov 3 01:00:00 GMT 2013
Sun Mar 9 02:00:00 GMT 2014 Sun Nov 2 01:00:00 GMT 2014
Sun Mar 8 02:00:00 GMT 2015 Sun Nov 1 01:00:00 GMT 2015
Sun Mar 13 02:00:00 GMT 2016 Sun Nov 6 01:00:00 GMT 2016
Sun Mar 12 02:00:00 GMT 2017 Sun Nov 5 01:00:00 GMT 2017
Sun Mar 11 02:00:00 GMT 2018 Sun Nov 4 01:00:00 GMT 2018
Sun Mar 10 02:00:00 GMT 2019 Sun Nov 3 01:00:00 GMT 2019
Sun Mar 8 02:00:00 GMT 2020 Sun Nov 1 01:00:00 GMT 2020
Sun Mar 14 02:00:00 GMT 2021 Sun Nov 7 01:00:00 GMT 2021
Sun Mar 13 02:00:00 GMT 2022 Sun Nov 6 01:00:00 GMT 2022
Sun Mar 12 02:00:00 GMT 2023 Sun Nov 5 01:00:00 GMT 2023
Sun Mar 10 02:00:00 GMT 2024 Sun Nov 3 01:00:00 GMT 2024
Sun Mar 9 02:00:00 GMT 2025 Sun Nov 2 01:00:00 GMT 2025
Sun Mar 8 02:00:00 GMT 2026 Sun Nov 1 01:00:00 GMT 2026
Sun Mar 14 02:00:00 GMT 2027 Sun Nov 7 01:00:00 GMT 2027
Sun Mar 12 02:00:00 GMT 2028 Sun Nov 5 01:00:00 GMT 2028
Sun Mar 11 02:00:00 GMT 2029 Sun Nov 4 01:00:00 GMT 2029
Sun Mar 10 02:00:00 GMT 2030 Sun Nov 3 01:00:00 GMT 2030
Sun Mar 9 02:00:00 GMT 2031 Sun Nov 2 01:00:00 GMT 2031
Sun Mar 14 02:00:00 GMT 2032 Sun Nov 7 01:00:00 GMT 2032
Sun Mar 13 02:00:00 GMT 2033 Sun Nov 6 01:00:00 GMT 2033
Sun Mar 12 02:00:00 GMT 2034 Sun Nov 5 01:00:00 GMT 2034
Sun Mar 11 02:00:00 GMT 2035 Sun Nov 4 01:00:00 GMT 2035
Sun Mar 9 02:00:00 GMT 2036 Sun Nov 2 01:00:00 GMT 2036
Sun Mar 8 02:00:00 GMT 2037 Sun Nov 1 01:00:00 GMT 2037
lyndon at frodo%
Every one of those should be offset by 30 minutes.
^ permalink raw reply [flat|nested] 11+ messages in thread* [9fans] time zones
2011-03-27 22:35 [9fans] time zones Lyndon Nerenberg (VE6BBM/VE7TFX)
@ 2011-03-28 2:04 ` erik quanstrom
2011-03-28 4:25 ` Lyndon Nerenberg
2011-03-31 19:32 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
0 siblings, 2 replies; 11+ messages in thread
From: erik quanstrom @ 2011-03-28 2:04 UTC (permalink / raw)
[no matches in 365 files]
On Sun Mar 27 18:35:55 EDT 2011, lyndon at orthanc.ca wrote:
> Even stranger, newfie time is not making sense. The Newf's have
> been half an hour off the rest of the world for ages. Yet:
>
> lyndon at frodo% cat Canada_Newfoundland | tzdump
> NST NDT
nope. the timezone is correct. i think the output of
tzdump is confusing. for us eastern, here's an example
; for(i in 4 5)date `{echo '1081044000 + 3600*'$i|hoc}
Sun Apr 4 01:00:00 EST 2004
Sun Apr 4 03:00:00 EDT 2004
and for newfoundland
; ifs=() timezone=`{cat tz/Canada_Newfoundland}for(i in 3 4)date `{echo '1081044000 + 3600*'$i|hoc}
Sun Apr 4 01:30:00 NST 2004
Sun Apr 4 03:30:00 NDT 2004
the reason for the confusion, is that the localtime
applies the offset before applying the dstpairs.
(/sys/src/libc/port/ctime.c) i belive i tripped on this
when i did the work for the us zones.
if there's a bug, it's in tzdump.
- erik
^ permalink raw reply [flat|nested] 11+ messages in thread* [9fans] time zones
2011-03-28 2:04 ` erik quanstrom
@ 2011-03-28 4:25 ` Lyndon Nerenberg
2011-03-31 19:32 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
1 sibling, 0 replies; 11+ messages in thread
From: Lyndon Nerenberg @ 2011-03-28 4:25 UTC (permalink / raw)
> if there's a bug, it's in tzdump.
could very well be. the time(2) manpage is a bit fuzzy about many things
timezone related. i'll go read the library source tomorrow.
^ permalink raw reply [flat|nested] 11+ messages in thread
* [9fans] time zones
2011-03-28 2:04 ` erik quanstrom
2011-03-28 4:25 ` Lyndon Nerenberg
@ 2011-03-31 19:32 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-31 19:55 ` erik quanstrom
1 sibling, 1 reply; 11+ messages in thread
From: Lyndon Nerenberg (VE6BBM/VE7TFX) @ 2011-03-31 19:32 UTC (permalink / raw)
> the reason for the confusion, is that the localtime
> applies the offset before applying the dstpairs.
> (/sys/src/libc/port/ctime.c) i belive i tripped on this
> when i did the work for the us zones.
Why this somewhat obscure format? Raw epoch (GMT) time() values seem
to be the obvious choice here.
Anyway, trying to sort this out is making me dizzy. And now that
April is almost here it's going to solve itself anyway :-P
^ permalink raw reply [flat|nested] 11+ messages in thread
* [9fans] time zones
2011-03-31 19:32 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
@ 2011-03-31 19:55 ` erik quanstrom
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
0 siblings, 2 replies; 11+ messages in thread
From: erik quanstrom @ 2011-03-31 19:55 UTC (permalink / raw)
On Thu Mar 31 15:34:21 EDT 2011, lyndon at orthanc.ca wrote:
> > the reason for the confusion, is that the localtime
> > applies the offset before applying the dstpairs.
> > (/sys/src/libc/port/ctime.c) i belive i tripped on this
> > when i did the work for the us zones.
>
> Why this somewhat obscure format? Raw epoch (GMT) time() values seem
> to be the obvious choice here.
i think the answer to this is obvious.
if it weren't done this way, then the dstpairs would be
unique to the timezone. each timezone would require
a unique list of dstpairs.
the way it is, the same dstpair list may be used for every
timezone with the same dst law. the same set of dstpairs
can be used for every us location. (ok, for places that don't
do dst, the pairs are unnecessary.) only the first line of the
zone needs changes.
further, the time of the change is easy to see in GMT.
that's a big advantage when double-checking your work.
why don't you just pull the new zones from sources?
it's all fixed, and integrated.
- erik
^ permalink raw reply [flat|nested] 11+ messages in thread
* [9fans] time zones
2011-03-31 19:55 ` erik quanstrom
@ 2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-31 23:08 ` erik quanstrom
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
1 sibling, 1 reply; 11+ messages in thread
From: Lyndon Nerenberg (VE6BBM/VE7TFX) @ 2011-03-31 20:26 UTC (permalink / raw)
> if it weren't done this way, then the dstpairs would be
> unique to the timezone. each timezone would require
> a unique list of dstpairs.
The files are small (each will fit in a single fs block, for whatever
your favourite fs is), but the header line makes each one unique
anyway, so there's no saving in disk space for, say, venti.
It just seems odd that that GMT wasn't the obvious base for these
values. Having spent a couple of years living inside the caldav mess,
I have an intense loathing of DST to begin with ...
But simplicity would seem to trump here, no? Fixing ctime.c to deal
with GMT is trivial, vs. trying to screw your head around which
(non-)DST timezone you're referencing as you walk though those files?
Is it Friday? I need a pint of Old Peculiar. Ooooh -- tomorrow is
April 1. Let's punt this conversation for 24 hours. (Or is that 23?
:-))
--lyndon
^ permalink raw reply [flat|nested] 11+ messages in thread
* [9fans] time zones
2011-03-31 19:55 ` erik quanstrom
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
@ 2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
1 sibling, 0 replies; 11+ messages in thread
From: Lyndon Nerenberg (VE6BBM/VE7TFX) @ 2011-03-31 20:26 UTC (permalink / raw)
> why don't you just pull the new zones from sources?
> it's all fixed, and integrated.
Where was the slashdot announcement?!?
^ permalink raw reply [flat|nested] 11+ messages in thread
* [9fans] time zones
@ 2011-03-27 22:33 Lyndon Nerenberg (VE6BBM/VE7TFX)
0 siblings, 0 replies; 11+ messages in thread
From: Lyndon Nerenberg (VE6BBM/VE7TFX) @ 2011-03-27 22:33 UTC (permalink / raw)
Even stranger, newfie time is not making sense. The Newf's have
been half an hour off the rest of the world for ages. Yet:
lyndon at frodo% cat Canada_Newfoundland | tzdump
NST NDT
Sun Apr 26 02:00:00 GMT 1970 Sun Oct 25 01:00:00 GMT 1970
Sun Apr 25 02:00:00 GMT 1971 Sun Oct 31 01:00:00 GMT 1971
Sun Apr 30 02:00:00 GMT 1972 Sun Oct 29 01:00:00 GMT 1972
Sun Apr 29 02:00:00 GMT 1973 Sun Oct 28 01:00:00 GMT 1973
Sun Apr 28 02:00:00 GMT 1974 Sun Oct 27 01:00:00 GMT 1974
Sun Apr 27 02:00:00 GMT 1975 Sun Oct 26 01:00:00 GMT 1975
Sun Apr 25 02:00:00 GMT 1976 Sun Oct 31 01:00:00 GMT 1976
Sun Apr 24 02:00:00 GMT 1977 Sun Oct 30 01:00:00 GMT 1977
Sun Apr 30 02:00:00 GMT 1978 Sun Oct 29 01:00:00 GMT 1978
Sun Apr 29 02:00:00 GMT 1979 Sun Oct 28 01:00:00 GMT 1979
Sun Apr 27 02:00:00 GMT 1980 Sun Oct 26 01:00:00 GMT 1980
Sun Apr 26 02:00:00 GMT 1981 Sun Oct 25 01:00:00 GMT 1981
Sun Apr 25 02:00:00 GMT 1982 Sun Oct 31 01:00:00 GMT 1982
Sun Apr 24 02:00:00 GMT 1983 Sun Oct 30 01:00:00 GMT 1983
Sun Apr 29 02:00:00 GMT 1984 Sun Oct 28 01:00:00 GMT 1984
Sun Apr 28 02:00:00 GMT 1985 Sun Oct 27 01:00:00 GMT 1985
Sun Apr 27 02:00:00 GMT 1986 Sun Oct 26 01:00:00 GMT 1986
Sun Apr 5 02:00:00 GMT 1987 Sun Oct 25 01:00:00 GMT 1987
Sun Apr 3 02:00:00 GMT 1988 Sun Oct 30 01:00:00 GMT 1988
Sun Apr 2 02:00:00 GMT 1989 Sun Oct 29 01:00:00 GMT 1989
Sun Apr 1 02:00:00 GMT 1990 Sun Oct 28 01:00:00 GMT 1990
Sun Apr 7 02:00:00 GMT 1991 Sun Oct 27 01:00:00 GMT 1991
Sun Apr 5 02:00:00 GMT 1992 Sun Oct 25 01:00:00 GMT 1992
Sun Apr 4 02:00:00 GMT 1993 Sun Oct 31 01:00:00 GMT 1993
Sun Apr 3 02:00:00 GMT 1994 Sun Oct 30 01:00:00 GMT 1994
Sun Apr 2 02:00:00 GMT 1995 Sun Oct 29 01:00:00 GMT 1995
Sun Apr 7 02:00:00 GMT 1996 Sun Oct 27 01:00:00 GMT 1996
Sun Apr 6 02:00:00 GMT 1997 Sun Oct 26 01:00:00 GMT 1997
Sun Apr 5 02:00:00 GMT 1998 Sun Oct 25 01:00:00 GMT 1998
Sun Apr 4 02:00:00 GMT 1999 Sun Oct 31 01:00:00 GMT 1999
Sun Apr 2 02:00:00 GMT 2000 Sun Oct 29 01:00:00 GMT 2000
Sun Apr 1 02:00:00 GMT 2001 Sun Oct 28 01:00:00 GMT 2001
Sun Apr 7 02:00:00 GMT 2002 Sun Oct 27 01:00:00 GMT 2002
Sun Apr 6 02:00:00 GMT 2003 Sun Oct 26 01:00:00 GMT 2003
Sun Apr 4 02:00:00 GMT 2004 Sun Oct 31 01:00:00 GMT 2004
Sun Apr 3 02:00:00 GMT 2005 Sun Oct 30 01:00:00 GMT 2005
Sun Apr 2 02:00:00 GMT 2006 Sun Oct 29 01:00:00 GMT 2006
Sun Mar 11 02:00:00 GMT 2007 Sun Nov 4 01:00:00 GMT 2007
Sun Mar 9 02:00:00 GMT 2008 Sun Nov 2 01:00:00 GMT 2008
Sun Mar 8 02:00:00 GMT 2009 Sun Nov 1 01:00:00 GMT 2009
Sun Mar 14 02:00:00 GMT 2010 Sun Nov 7 01:00:00 GMT 2010
Sun Mar 13 02:00:00 GMT 2011 Sun Nov 6 01:00:00 GMT 2011
Sun Mar 11 02:00:00 GMT 2012 Sun Nov 4 01:00:00 GMT 2012
Sun Mar 10 02:00:00 GMT 2013 Sun Nov 3 01:00:00 GMT 2013
Sun Mar 9 02:00:00 GMT 2014 Sun Nov 2 01:00:00 GMT 2014
Sun Mar 8 02:00:00 GMT 2015 Sun Nov 1 01:00:00 GMT 2015
Sun Mar 13 02:00:00 GMT 2016 Sun Nov 6 01:00:00 GMT 2016
Sun Mar 12 02:00:00 GMT 2017 Sun Nov 5 01:00:00 GMT 2017
Sun Mar 11 02:00:00 GMT 2018 Sun Nov 4 01:00:00 GMT 2018
Sun Mar 10 02:00:00 GMT 2019 Sun Nov 3 01:00:00 GMT 2019
Sun Mar 8 02:00:00 GMT 2020 Sun Nov 1 01:00:00 GMT 2020
Sun Mar 14 02:00:00 GMT 2021 Sun Nov 7 01:00:00 GMT 2021
Sun Mar 13 02:00:00 GMT 2022 Sun Nov 6 01:00:00 GMT 2022
Sun Mar 12 02:00:00 GMT 2023 Sun Nov 5 01:00:00 GMT 2023
Sun Mar 10 02:00:00 GMT 2024 Sun Nov 3 01:00:00 GMT 2024
Sun Mar 9 02:00:00 GMT 2025 Sun Nov 2 01:00:00 GMT 2025
Sun Mar 8 02:00:00 GMT 2026 Sun Nov 1 01:00:00 GMT 2026
Sun Mar 14 02:00:00 GMT 2027 Sun Nov 7 01:00:00 GMT 2027
Sun Mar 12 02:00:00 GMT 2028 Sun Nov 5 01:00:00 GMT 2028
Sun Mar 11 02:00:00 GMT 2029 Sun Nov 4 01:00:00 GMT 2029
Sun Mar 10 02:00:00 GMT 2030 Sun Nov 3 01:00:00 GMT 2030
Sun Mar 9 02:00:00 GMT 2031 Sun Nov 2 01:00:00 GMT 2031
Sun Mar 14 02:00:00 GMT 2032 Sun Nov 7 01:00:00 GMT 2032
Sun Mar 13 02:00:00 GMT 2033 Sun Nov 6 01:00:00 GMT 2033
Sun Mar 12 02:00:00 GMT 2034 Sun Nov 5 01:00:00 GMT 2034
Sun Mar 11 02:00:00 GMT 2035 Sun Nov 4 01:00:00 GMT 2035
Sun Mar 9 02:00:00 GMT 2036 Sun Nov 2 01:00:00 GMT 2036
Sun Mar 8 02:00:00 GMT 2037 Sun Nov 1 01:00:00 GMT 2037
lyndon at frodo%
Every one of those should be offset by 30 minutes.
^ permalink raw reply [flat|nested] 11+ messages in thread
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2011-03-27 22:35 [9fans] time zones Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-28 2:04 ` erik quanstrom
2011-03-28 4:25 ` Lyndon Nerenberg
2011-03-31 19:32 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-31 19:55 ` erik quanstrom
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-03-31 23:08 ` erik quanstrom
2011-03-31 23:24 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
2011-04-01 7:21 ` Richard Miller
2011-03-31 20:26 ` Lyndon Nerenberg (VE6BBM/VE7TFX)
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2011-03-27 22:33 Lyndon Nerenberg (VE6BBM/VE7TFX)
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