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[PROPOSED] Shanks is likely wrong about Maputo switch to CAT
by Paul Eggert April 9, 2024

April 9, 2024

* NEWS: Mention the change, and leave room for future Portugal fixes. * africa (Africa/Maputo): Tweak LMT to match London Gazette, and change CAT transition date to a guess of 1909. --- NEWS | 4 ++++ africa | 19 ++++++++++++++----- 2 files changed, 18 insertions(+), 5 deletions(-) diff --git a/NEWS b/NEWS index 25d939f1..0d6a1513 100644 --- a/NEWS +++ b/NEWS @@ -4,6 +4,7 @@ Unreleased, experimental changes Briefly: The main data form now uses %z. + Improve historical data for Portugal and possessions. Changes to data @@ -15,6 +16,9 @@ Unreleased, experimental changes the represented data: the generated TZif files are unchanged. Rearguard form still avoids %z, to support obsolescent parsers. + Some transitions for Portugal and possessions have been changed. + This affects timestamps for Africa/Maputo before 1909. + Asia/Almaty has been removed from zonenow.tab as it now agrees with Asia/Tashkent for future timestamps, due to Kazakhstan's 2024-02-29 time zone change. Similarly, America/Scoresbysund diff --git a/africa b/africa index a731dbee..695d66ed 100644 --- a/africa +++ b/africa @@ -1101,13 +1101,22 @@ Zone Africa/El_Aaiun -0:52:48 - LMT 1934 Jan # El Aaiún # Zambia # Zimbabwe # -# Shanks gives 1903-03-01 for the transition to CAT. -# Perhaps the 1911-05-26 Portuguese decree -# https://dre.pt/pdf1sdip/1911/05/12500/23132313.pdf -# merely made it official? +# From Paul Eggert (2024-04-09): +# The London Gazette, 1903-04-03, page 2245, says that +# as of 1903-03-03 a time ball at the port of Lourenço Marques +# (as Maputo was then called) was dropped daily at 13:00:00 LMT, +# corresponding to 22:49:41.7 GMT; round this to UT+2:10:18. +# Conversely, the newspaper South Africa, 1909-02-09, page 321, +# says the port had just installed an apparatus that communicated +# "from the controlling clock in the new Observatory at Reuben Point ... +# exact mean South African time, i.e., 30 deg., or 2 hours East of Greenwich". +# Although Shanks gives 1903-03-01 for the transition to CAT, +# evidently the port transitioned to CAT after 1903-03-03 but before +# the Portuguese legal transition of 1912-01-01 (see Europe/Lisbon commentary). +# For lack of better info, list 1909 as the transition date. # # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone Africa/Maputo 2:10:20 - LMT 1903 Mar +Zone Africa/Maputo 2:10:18 - LMT 1909 2:00 - CAT # Namibia -- 2.44.0

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Using %z in FORMAT column of 'europe' etc.
by Paul Eggert April 8, 2024

April 8, 2024

[This is a repost with minor updates of <https://mm.icann.org/pipermail/tz/2024-March/058790.html>. This repost is in a separate email thread, with a clearer "Subject:" line.] The recent glitches with %z-related lines in the Portugal data lead me to think that it's time to start using %z in the main format. For example, instead of this: > # Zone NAME STDOFF RULES FORMAT [UNTIL] > Zone Atlantic/Azores -1:42:40 - LMT 1884 # Ponta Delgada > -1:54:32 - HMT 1912 Jan 1 2:00u # Horta MT > -2:00 Port -02/-01 1942 Apr 25 22:00s > -2:00 Port +00 1942 Aug 15 22:00s > -2:00 Port -02/-01 1943 Apr 17 22:00s > -2:00 Port +00 1943 Aug 28 22:00s > -2:00 Port -02/-01 1944 Apr 22 22:00s > -2:00 Port +00 1944 Aug 26 22:00s > -2:00 Port -02/-01 1945 Apr 21 22:00s > -2:00 Port +00 1945 Aug 25 22:00s > -2:00 Port -02/-01 1966 Apr 3 2:00 > -1:00 Port -01/+00 1983 Sep 25 1:00s > -1:00 W-Eur -01/+00 1992 Sep 27 1:00s the 'europe' file should contain this: > # Zone NAME STDOFF RULES FORMAT [UNTIL] > Zone Atlantic/Azores -1:42:40 - LMT 1884 # Ponta Delgada > -1:54:32 - HMT 1912 Jan 1 2:00u # Horta MT > -2:00 Port %z 1966 Apr 3 2:00 > -1:00 Port %z 1983 Sep 25 1:00s > -1:00 W-Eur %z 1992 Sep 27 1:00s This would eventually simplify future maintenance and help avoid similar glitches in the future. For now, the 'rearguard' format would continue to avoid %z in the FORMAT column. It's reasonable to use %z in 'europe' now, as zic has supported %z since release 2015f.

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[PROPOSED] Treat W-Eur like Port when reguarding
by Paul Eggert April 8, 2024

April 8, 2024

* ziguard.awk: When deciding among vanguard, main and rearguard forms, treat W-Eur lines like Port lines, since Portuguese zones use both. This should simplify future changes. --- ziguard.awk | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/ziguard.awk b/ziguard.awk index a5fd5491..066f3b10 100644 --- a/ziguard.awk +++ b/ziguard.awk @@ -142,7 +142,7 @@ DATAFORM != "main" { # If this line should differ due to Portugal benefiting from %z if supported, # uncomment the desired version and comment out the undesired one. - if ($0 ~ /^#?[\t ]+-[12]:00[\t ]+(Port[\t ]+[%+-]|-[\t ]+(%z|-01)[\t ]+1982 Mar 28)/) { + if ($0 ~ /^#?[\t ]+-[12]:00[\t ]+((Port|W-Eur)[\t ]+[%+-]|-[\t ]+(%z|-01)[\t ]+1982 Mar 28)/) { if (($0 ~ /%z/) == (DATAFORM == "vanguard")) { uncomment = in_comment } else { -- 2.40.1

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Wrong symlinks with BACKWARD=backward PACKRATDATA=backzone
by Benjamin Drung April 8, 2024

April 8, 2024

Hi, the Debian/Ubuntu package uses BACKWARD=backward PACKRATDATA=backzone. The resulting tzdata.zi has the timezone Africa/Asmara, but Africa/Asmera points to Africa/Nairobi instead of the existing Africa/Asmara: ``` $ make AWK=gawk BACKWARD="backward" PACKRATDATA=backzone PACKRATLIST=zone.tab VERSION_DEPS= tzdata.zi gawk \ -v DATAFORM=`expr main.zi : '$.*$.zi'` \ -v PACKRATDATA='backzone' \ -v PACKRATLIST='zone.tab' \ -f ziguard.awk \ africa antarctica asia australasia europe northamerica southamerica etcetera factory backward backzone >main.zi.out mv main.zi.out main.zi { (type git) >/dev/null 2>&1 && \ V=`git describe --match '[0-9][0-9][0-9][0-9][a-z]*' \ --abbrev=7 --dirty` || \ if test 'unknown' = unknown && V=`cat version`; then \ case $V in *-dirty);; *) V=$V-dirty;; esac; \ else \ V='unknown'; \ fi; } && \ printf '%s\n' "$V" >version.out mv version.out version version=`sed 1q version` && \ LC_ALL=C gawk \ -v dataform='main' \ -v deps='ziguard.awk africa antarctica asia australasia europe northamerica southamerica etcetera factory backward backzone zone.tab zishrink.awk' \ -v redo='posix_right' \ -v version="$version" \ -f zishrink.awk \ main.zi >tzdata.zi.out mv tzdata.zi.out tzdata.zi $ grep Asmera tzdata.zi L Africa/Nairobi Africa/Asmera ``` Can this fixed/configured? -- Benjamin Drung Debian & Ubuntu Developer

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[PATCH v2] tzfile.5: Fix indentation
by Alejandro Colomar April 8, 2024

April 8, 2024

RS after IP, if the indentation amount is not specified, takes the same indentation that IP had. The values being used were wrong, and by removing them, we're fixing the indentation of the page. Also, one RS was not just incorrect, but completely unnecessary, and there was a missing RE. Cc: "G. Branden Robinson" <branden(a)debian.org> Cc: Paul Eggert <eggert(a)cs.ucla.edu> Signed-off-by: Alejandro Colomar <alx(a)kernel.org> --- tzfile.5 | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/tzfile.5 b/tzfile.5 index 867348d6..aa6b858d 100644 --- a/tzfile.5 +++ b/tzfile.5 @@ -42,7 +42,7 @@ .SH DESCRIPTION Fifteen bytes containing zeros reserved for future use. .IP \(bu Six four-byte integer values, in the following order: -.RS "\w' \(bu 'u" +.RS .TP "\w' 'u" .B tzh_ttisutcnt The number of UT/local indicators stored in the file. @@ -66,6 +66,7 @@ .SH DESCRIPTION The number of bytes of time zone abbreviation strings stored in the file. .RE +.RE .PP The above header is followed by the following fields, whose lengths depend on the contents of the header: @@ -134,8 +135,7 @@ .SH DESCRIPTION is in the range [\-89999, 93599] (i.e., more than \-25 hours and less than 26 hours); this allows easy support by implementations that already support the POSIX-required range [\-24:59:59, 25:59:59]. -.RS "\w' 'u" -.IP \(bu "\w'\(bu 'u" +.IP \(bu .B tzh_charcnt bytes that represent time zone designations, which are null-terminated byte strings, each indexed by the -- 2.43.0

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Unearthly time zone in the news
by Arthur David Olson April 7, 2024

April 7, 2024

"Moon Standard Time? Nasa to create lunar-centric time reference system: Space agency tasked with establishing Coordinated Lunar Time, partly to aid missions requiring extreme precision" Not to be missed: the opportunity to have neap seconds. @dashdashado https://www.theguardian.com/science/2024/apr/02/moon-nasa-coordinated-lunar…

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[PROPOSED] America/Scoresbysund matches America/Nuuk from now on
by Paul Eggert April 3, 2024

April 3, 2024

This pacifies ‘make check_now’. * NEWS: Mention this. * zonenow.tab: Remove America/Scoresbysund. --- NEWS | 4 +++- zonenow.tab | 2 -- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/NEWS b/NEWS index 8efa195f..54dcd21b 100644 --- a/NEWS +++ b/NEWS @@ -6,7 +6,9 @@ Unreleased, experimental changes Asia/Almaty has been removed from zonenow.tab as it now agrees with Asia/Tashkent for future timestamps, due to Kazakhstan's - 2024-02-29 time zone change. + 2024-02-29 time zone change. Similarly, America/Scoresbysund + has been removed, as it how agrees with America/Nuuk due to + its 2024-03-31 time zone change. Release 2024a - 2024-02-01 09:28:56 -0800 diff --git a/zonenow.tab b/zonenow.tab index 1e7a86be..84f27e93 100644 --- a/zonenow.tab +++ b/zonenow.tab @@ -123,8 +123,6 @@ XX +1455-02331 Atlantic/Cape_Verde Cape Verde # # -01/+00 (EU DST) XX +3744-02540 Atlantic/Azores Azores -# -01/+00 (EU DST) until 2024-03-31; then -02/-01 (EU DST) -XX +7029-02158 America/Scoresbysund Ittoqqortoormiit # # +00 - GMT XX +0519-00402 Africa/Abidjan far western Africa; Iceland ("GMT") -- 2.40.1

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vzic link in tz-link.html
by Allen Winter March 28, 2024

March 28, 2024

Hi, I'm the current maintainer of vzic. We moved the project from sourceforge to github many years ago and I've been informed that your tz-link.html page still points to the old sourceforge url. Please update tz-link.html so that the vzic link points to https://github.com/libical/vzic

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Negative leap second in main stream media.
by Arthur David Olson March 28, 2024

March 28, 2024

'...although the core is causing the planet to spin faster, the planetary shape changes caused by a warming climate are slowing that process. Absent this effect...the overall acceleration of the planet’s rotation might require timekeepers to insert a “negative leap second” at the end of 2026. Because of climate change, that might not be necessary until 2029.' "Climate change is altering Earth’s rotation enough to mess with our clocks," Washington Post, 2024-03-28. Behind a paywall: https://www.washingtonpost.com/science/2024/03/27/leap-second-melting-poles… @dashdashado

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Asia/Tehran +3:30
by Mohammad Farshad March 28, 2024

March 28, 2024

Dear Sir/Madam I think the time zone of Theran/Iran is not correct in the 2024a version. "After returning to the standard time on 22 September 2022, the Iran Government elected to remain permanently in the standard time, cancelling daylight saving time. Hence, Iran will permanently remain at UTC + 3:30 time zone going forward." Link: Iran 2023 time zone update now available - Microsoft Community Hub <https://techcommunity.microsoft.com/t5/daylight-saving-time-time-zone/iran-….> Best regards, Mohammad farshad

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