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Vadsø, Norway mayor wants 26-hour days
by Paul Eggert April 15, 2024

April 15, 2024

On March 20 Wenche Pedersen, the mayor of Vadsø municipality, Norway, asked[1] the European Commission to issue a directive allowing Norway to create a separate time zone for the northern part of Norway. Days in the new time zone would contain 26 hours instead of the usual 24. This request is part of the "MOREtime" project. Mayor Pedersen wrote: > ... we aim to celebrate and promote this unique way of life, offering individuals the opportunity to enjoy more quality time engaging in activities such as fishing, hunting, learning new languages, or simply being with loved ones. By having our own certified time zone within the EU, we hope to attract more young people, not only from Norway but also from around the world, to discover and settle in this adventurous area. Recently the mayor's proposal has been covered by several major news organizations. When asked how the 26-hour day would actually work, the mayor replied "We haven't thought a lot about that. The clock will go from 12 to 13 ... and we have to see how this will go. I don't think they're going to say yes so we haven't thought about all the details."[2] Longtime readers of the time zone mailing list might remember that in 2019 a resident of Sommarøy, Norway petitioned his parliamentarian to abolish civil time in his town, something that also made the news.[3] However, the Sommarøy proposal was by a private individual and was easily implementable via tzdata by creating a new UTC or LMT zone with abbreviation "-00" or "LMT", whereas the Vadsø proposal is by the mayor, and would require changes to tzcode and would therefore be considerably harder to support. Although it's unlikely that the Vadsø proposal will go anywhere, it's helpful to think of how timekeeping changes like this might be accommodated by the TZDB project, as similar proposals might happen in the future. I see several ways to implement 26-hour days, falling into two major categories. Category I: Shorten civil-time hours so that there are 26 civil-time hours in a standard-length (SI) day. Four possible ways to do this are: A. Civil-time seconds are 12/13 s (i.e., 12/13 of an SI second, or about 0.923 s), so that civil-time minutes and hours are both 12/13 of their SI counterparts. B. Civil-time seconds are the same as before, but civil-time minutes are 60 * 12/13 s (i.e., about 55.38 s). C. Civil-time seconds and minutes are the same as before, but civil-time hours are 60 * 12/13 min (i.e., about 55.38 SI minutes). D. Civil-time minutes are 60 * sqrt(12/13) s (about 57.65 s), and civil-time hours are 60 * sqrt(12/13) civil-time minutes (i.e., about 57.65 civil-time minutes). Category II: Adjust day lengths so that all or most days contain 26 SI hours. Three possibilities here are: E. Civil-time days are 26 SI hours, and the calendar gradually falls further and further behind the Gregorian calendar. F. Civil-time days are 26 SI hours, but skip every 13th day so that days stay roughly synchronized with the Gregorian calendar. G. At the end of every day, move clocks backward two hours, from 24:00 to 22:00, so that timestamps from 22:00:00 through 23:59:59 repeat. Do this consistently for eleven days, thus moving clocks backward a total of 22 hours. On the twelfth day move clocks forward 22 hours instead, from 24:00 to 22:00 the next day. Repeat this cycle indefinitely. This way, eleven days out of thirteen contain 26 hours, and the next two days combined also contain 26 hours - 24 hours in the twelfth day and 2 hours in the thirteenth. Of these methods something like (G) would be the most compatible with computerized timekeeping, as (G) conforms to POSIX-1.202x Draft 4.1[4] whereas (A) through (F) do not. (G) avoids timestamps like 25:30; G's hours, minutes or seconds are all of the usual lengths; and (G) contains only transitions that are like daylight-saving transitions that computerized timekeeping can already deal with. Although a downside of (G) is that at times the sun will be at its zenith at midnight, I assume Vadsø residents are already accustomed to midnight suns so this disadvantage is relatively minor for them. Another downside of (G) is that clocks will never go "from 12 to 13" as the mayor requested, but given the major technical difficulties of (A) through (F) I hope the mayor would appreciate that (G) may be the best we can practically hope for in today's standardized and computerized world. Unfortunately even (G) would require some changes to tzcode and tzdata to become practical, and it would take many years for these changes to propagate to devices in common use in Vadsø. So, unless Vadsø residents are prepared to change their clocks by hand every day for the next several years, it does not appear that the mayor's proposal will be practical any time soon. I am sending this email to the time zone mailing list, as perhaps someone on the list can think of even better ways to implement the mayor's request. I am also cc'ing this email to Mayor Pedersen to give her a heads-up about this analysis, should it ever be needed in Vadsø. [1]: https://kommunikasjon.ntb.no/files/17848798/18066114/57109/no [2]: https://www.politico.eu/article/norway-arctic-region-asks-eu-commission-for… [3]: https://mm.icann.org/pipermail/tz/2019-June/028154.html [4]: https://www.opengroup.org/austin/

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Kazakhstan Airline Schedules
by Owen Leibman April 14, 2024

April 14, 2024

I have a friend in Kazakhstan whom, thanks to this list, I notified about the recent time change before it was widely known in the country. She says the transition was pretty smooth, but, over a month later, sent me a message, which I pass on (without the attachments showing the discrepancies) as an anecdotal demonstration of how hard it is to get all the pieces in place: Happy eclipse day! I'm sending an update for your friends on time zones and flights. I booked a flight in February to Frankfurt leaving this Wednesday. United says the flight departs 4:20 a.m., but Lufthansa sent me an email saying I could check in for my flight which leaves at 3:20 a.m. Yet another Lufthansa check-in screen and the boarding pass says it leaves at 4:20. Meanwhile FlightAware claims the flight is not leaving till 5:20 a.m. All have the same arrival time of 9 a.m. Nursultan airport website does not list the flight yet. I will let you know which one proves to be right! I think it's 4:20. This email and any files transmitted with it are confidential, proprietary and intended solely for the individual or entity to whom they are addressed. If you have received this email in error please delete it immediately.

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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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