- tz - lists.iana.org

zoneinfo generating issues
by 汪蒙蒙（木之） March 17, 2021

March 17, 2021

Hi: Recently, I wanted to write a program to watch the change of timezone database. I got newest version from this address: https://data.iana.org/time-zones/releases/tzdata2021a.tar.gz. I used zic (version: zic (tzcode) 2020c, system: CentOS Linux release 7.6.1810 (Core)) to generate the zoneinfo. I pick up some zones with local timeto calculate utc time to verify the changes using both the new and currently used version tzdata, here is diff: zone local time by 2021a utc time by 2020d utc time America/Adak 2022-11-01 00:00:00 2022-11-01 09:00:00 2022-11-01 10:00:00 America/Anchorage 2022-11-01 00:00:00 2022-11-01 08:00:00 2022-11-01 09:00:00 America/Asuncion 2022-10-01 00:00:00 2022-10-01 04:00:00 2022-10-01 03:00:00 America/Atka 2022-11-01 00:00:00 2022-11-01 09:00:00 2022-11-01 10:00:00 Those zones are not changed from version 2020d to 2021a. I am very confused and not sure if I generated the zoneinfo in the right way. Here was what do: # mkdir zoneinfo # cd tzdata2021a # zic -d ../zoneinfo -L ./leapseconds africa antarctica asia australasia europe northamerica southamerica etcetera backward factory I was wondering if you could provide me some help. I really appreciate your reply. Sincerely, wangmm

11 27

Should tzfile.5 list the time zone designations field more explicitly?
by Ian Abbott March 17, 2021

March 17, 2021

The description of the local time types entries mentions the array of time zone abbreviation bytes in passing, but that probably deserves its own list item. On skimming over the man page, it looks like the local time type entries are immediately followed by the leap-second correction records. -- -=( Ian Abbott <abbotti(a)mev.co.uk> || MEV Ltd. is a company )=- -=( registered in England & Wales. Regd. number: 02862268. )=- -=( Regd. addr.: S11 & 12 Building 67, Europa Business Park, )=- -=( Bird Hall Lane, STOCKPORT, SK3 0XA, UK. || www.mev.co.uk )=-

2 2

[PROPOSED] Improve coverage of version 4 interoperability
by Paul Eggert March 17, 2021

March 17, 2021

* tzfile.5: Mention problems with version 3-only readers and version 4 files, and update other interoperability coverage. --- tzfile.5 | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/tzfile.5 b/tzfile.5 index 8ee6cfb..b4952d5 100644 --- a/tzfile.5 +++ b/tzfile.5 @@ -243,10 +243,13 @@ Readers that only understand Version 1 must ignore any data that extends beyond the calculated end of the version 1 data block. .PP -Writers should generate a version 3 file if +Other than version 1, writers should generate +the lowest version number needed by a file's data. +For example, a writer should generate a version 3 file +if the file does not contain a truncated leap second table +and so does not use version 4 features, but TZ string extensions are necessary to accurately -model transition times. -Otherwise, version 2 files should be generated. +model transition times so the file does need version 3 features. .PP The sequence of time changes defined by the version 1 header and data block should be a contiguous subsequence @@ -269,7 +272,7 @@ and This is for compatibility with POSIX requirements for time zone abbreviations. .PP -When reading a version 2 or 3 file, readers +When reading a version 2+ file, readers should ignore the version 1 header and data block except for the purpose of skipping over them. .PP @@ -328,6 +331,10 @@ for the next time zone east, e.g., .q "AST4" for permanent Atlantic Standard Time (\-04). .IP * +Some readers designed for earlier versions reject version 4 files, +because they require complete leap second tables that do not record +expiration dates. +.IP * Some readers ignore the footer, and instead predict future timestamps from the time type of the last transition. As a partial workaround, a writer can output more transitions -- 2.27.0

1 0

[PATCH 1/7] localtime.c is less finicky about leap seconds
by Paul Eggert March 17, 2021

March 17, 2021

* localtime.c (tzloadbody): Do not reject a TZif file merely because its leap second table contains adjacent entries with equal corrections, or contains a first entry with a correction value other than +1 or -1. * NEWS: Mention this. --- NEWS | 5 +++++ localtime.c | 13 ++++++++++--- 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/NEWS b/NEWS index 0de05f3..d8676e6 100644 --- a/NEWS +++ b/NEWS @@ -39,6 +39,11 @@ Unreleased, experimental changes seconds error than with an hour error, so zic -L no longer truncates output in this way. + The TZif reader now allows the leap second table to begin with a + correction other than -1 or +1, and to contain adjacent + transitions with equal corrections. This supports possible + future extensions to the TZif format. + Fix bug that caused 'localtime' etc. to crash when TZ was set to a all-year DST string like "EST5EDT4,0/0,J365/25" that does not conform to POSIX but does conform to Internet RFC 8536. diff --git a/localtime.c b/localtime.c index 6627ff2..a086d4d 100644 --- a/localtime.c +++ b/localtime.c @@ -445,7 +445,7 @@ tzloadbody(char const *name, struct state *sp, bool doextend, int_fast32_t ttisstdcnt = detzcode(up->tzhead.tzh_ttisstdcnt); int_fast32_t ttisutcnt = detzcode(up->tzhead.tzh_ttisutcnt); int_fast64_t prevtr = 0; - int_fast32_t prevcorr = 0; + int_fast32_t prevcorr; int_fast32_t leapcnt = detzcode(up->tzhead.tzh_leapcnt); int_fast32_t timecnt = detzcode(up->tzhead.tzh_timecnt); int_fast32_t typecnt = detzcode(up->tzhead.tzh_typecnt); @@ -542,9 +542,16 @@ tzloadbody(char const *name, struct state *sp, bool doextend, and UTC months are at least 28 days long (minus 1 second for a negative leap second). Each leap second's correction must differ from the previous one's by 1 - second. */ + second or less, except that the first correction can be + any value; these requirements are more generous than + RFC 8536, to allow future RFC extensions. */ if (tr - prevtr < 28 * SECSPERDAY - 1 - || (corr != prevcorr - 1 && corr != prevcorr + 1)) + || ((timecnt == 0 || sp->ats[0] < tr) + && ! (i == 0 + || (prevcorr < corr + ? corr == prevcorr + 1 + : (corr == prevcorr + || corr == prevcorr - 1))))) return EINVAL; sp->lsis[leapcnt].ls_trans = prevtr = tr; sp->lsis[leapcnt].ls_corr = prevcorr = corr; -- 2.27.0

2 7

changing "master" to "main" in tzdb development repository
by Paul Eggert March 17, 2021

March 17, 2021

Because the word "master" has negative connotations in English, I renamed the "master" branch to "main" in the tzdb development repository <https://github.com/eggert/tz>. This follows in the wake of GitHub's October change that makes the default branch "main" rather than "master", and GitHub's followup changes in January that made renaming relatively painless - for example, web requests for "master" are now redirected to "main" automatically <https://github.com/github/renaming/>. This renaming by GitHub is part of a broader change within the Git software ecosystem <https://sfconservancy.org/news/2020/jun/23/gitbranchname/>. This change affects neither past nor future releases of tzdb. It affects only the small number of direct accesses to the development repository for commits between releases. The idea is that on balance the small inconvenience for developers is outweighed by the advantage in reducing insensitivity overall. If you are a developer with a local clone of the tzdb repository, please adjust to this change by running the following shell commands: $ git branch -m master main $ git fetch origin $ git branch -u origin/main main I've done this for my own local clone of the repository. To document this change for tzdb newcomers, I installed the attached patch to the CONTRIBUTING file just before renaming the branch.

8 8

Troubles with zone Asia/Gaza after tzdata2020b release
by Evgheni Antropov March 15, 2021

March 15, 2021

Dear tzdata maintainers, I have found that after tzdata2020b release something has gone wrong with Asia/Gaza timezone, which is related to Palestine. For checking I used this information https://www.timeanddate.com/worldclock/palestine/gaza and for DST at 2019: https://www.timeanddate.com/time/change/palestine/gaza?year=2019 for DST at 2020: https://www.timeanddate.com/time/change/palestine/gaza?year=2020 for DST at 2021: https://www.timeanddate.com/time/change/palestine/gaza?year=2021 I compiled all last release of tzdata from 2019c to 2021a and was comparing them with Ubuntu packages for 2020b on groovy (20.10) and 2021a on bionic (18.04). If several changes in the date of DST for different years can be related with last applied laws of DST in Palestine (described here http://mm.icann.org/pipermail/tz/2020-October/029376.html) but broken timezone output in letters or numbers is speaking about any error in the this time zone code. Can you investigate this too ? On screenshot you can see all my investigation: [cid:image002.png@01D70EDB.BE0D5350] Also I share all commands and listing for your execution itself: [root@Router8:~]# ls -la /etc/localtime lrwxrwxrwx 1 root root 35 Mar 4 2021 /etc/localtime -> /usr/share/zoneinfo/posix/Asia/Gaza [root@Router8:~]# ls -la /usr/share/zoneinfo/posix/Asia/Gaza* lrwxrwxrwx 1 root root 41 Mar 27 01:00 /usr/share/zoneinfo/posix/Asia/Gaza -> /usr/share/zoneinfo/posix/Asia/Gaza.2019c -rw-r--r-- 1 root root 2316 Oct 22 09:34 /usr/share/zoneinfo/posix/Asia/Gaza.2019c -rw-r--r-- 1 root root 2316 Oct 30 2020 /usr/share/zoneinfo/posix/Asia/Gaza.2020a -rw-r--r-- 1 root root 1166 Oct 30 2020 /usr/share/zoneinfo/posix/Asia/Gaza.2020b -rw-r--r-- 1 root root 1166 Oct 30 2020 /usr/share/zoneinfo/posix/Asia/Gaza.2020c -rw-r--r-- 1 root root 1195 Oct 30 2020 /usr/share/zoneinfo/posix/Asia/Gaza.2020d -rw-r--r-- 1 root root 1213 Mar 1 2021 /usr/share/zoneinfo/posix/Asia/Gaza.2021a -rw-r--r-- 1 root root 2316 Oct 19 2020 /usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2020b -rw-r--r-- 1 root root 2459 Jan 27 2021 /usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2021a [root@Router8:~]# date +"%Y%m%d %T" -s "20190328 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20190328 23:59:55 Thu Mar 28 23:59:59 2019 +0200 EET Fri Mar 29 01:00:01 2019 +0300 EEST [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.2020a /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.2020a' [root@Router8:~]# date +"%Y%m%d %T" -s "20200326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20200326 23:59:55 Thu Mar 26 23:59:59 2020 +0200 EET Fri Mar 27 01:00:01 2020 +0300 EEST [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.2020b /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.2020b' [root@Router8:~]# date +"%Y%m%d %T" -s "20200326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20200326 23:59:55 Thu Mar 26 23:59:59 2020 +0000 Fri Mar 27 00:00:01 2020 +0000 [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.2020c /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.2020c' [root@Router8:~]# date +"%Y%m%d %T" -s "20200326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20200326 23:59:55 Thu Mar 26 23:59:59 2020 +0000 Fri Mar 27 00:00:01 2020 +0000 [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2020b /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2020b' [root@Router8:~]# date +"%Y%m%d %T" -s "20200326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20200326 23:59:55 Thu Mar 26 23:59:59 2020 +0200 EET Fri Mar 27 01:00:01 2020 +0300 EEST [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.2021a /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.2021a' [root@Router8:~]# date +"%Y%m%d %T" -s "20210326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20210326 23:59:55 Fri Mar 26 23:59:59 2021 +0000 Sat Mar 27 00:00:01 2021 +0000 [root@Router8:~]# ln -sfv /usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2021a /usr/share/zoneinfo/posix/Asia/Gaza '/usr/share/zoneinfo/posix/Asia/Gaza' -> '/usr/share/zoneinfo/posix/Asia/Gaza.ubuntu.2021a' [root@Router8:~]# date +"%Y%m%d %T" -s "20210326 23:59:55" ; sleep 4; date +%c%t%z%t%Z; sleep 2 ; date +%c%t%z%t%Z 20210326 23:59:55 Fri Mar 26 23:59:59 2021 +0200 EET Sat Mar 27 01:00:01 2021 +0300 EEST Best regards, [cid:image001.jpg@01D70EC7.959CF010] Evgheni Antropov Software R&D Engineer +373 22 404 665 www.addgrup.com<http://www.addgrup.com/>

4 12

Re: [tz] [PROPOSED] Fix Sierra Leone typo for 1957
by REMI ACIEN March 11, 2021

March 11, 2021

For Sierra Leone : -0:53:00 - FMT 1913 Jun # Freetown Mean Time. Envoyé depuis mon appareil Galaxy

2 1

Re: [tz] Some time zone history (4) (P Chan)
by Yandex.ru March 9, 2021

March 9, 2021

On Wed, Mar 03, 2021 at 04:22:48PM +0000, P Chan via tz wrote: > Russia > … > The 1922 transition in Moscow seems to be wrong. The 1922 transition in Moscow is true, that confirmed by law: +1h on 15.02.1922 at 23:00 Msk https://www.lawmix.ru/zakonodatelstvo/2575961 -1h on 30.09.1922 at 24:00 Msk https://www.lawmix.ru/zakonodatelstvo/2575587

1 0

Some time zone history (4)
by P Chan March 8, 2021

March 8, 2021

Russia Before 14 February 1918, Julian calendar was used in Russia. Therefore for the 1917 transitions in tz, 1 July should be 14 July and 28 December should be 10 January 1918. Decrees for the 1917 forward transition: http://docs.historyrussia.org/ru/nodes/33879#mode/inspect/page/1/zoom/4 http://docs.historyrussia.org/ru/nodes/33986#mode/inspect/page/4/zoom/4 http://docs.historyrussia.org/ru/nodes/34925#mode/inspect/page/3/zoom/4 In 1920, there were four transitions, the dates were the same as 1921. http://docs.historyrussia.org/ru/nodes/16730#mode/inspect/page/1/zoom/4 http://docs.historyrussia.org/ru/nodes/16813#mode/inspect/page/1/zoom/4 http://docs.historyrussia.org/ru/nodes/21879#mode/inspect/page/1/zoom/4 The 1922 transition in Moscow seems to be wrong. Instead, there should be a transition in 1924. http://www.libussr.ru/doc_ussr/ussr_1984.htm You may also refer to a section on the Russian Wikipedia. https://ru.wikipedia.org/wiki/%D0%92%D1%80%D0%B5%D0%BC%D1%8F_%D0%B2_%D0%A0%… ----- Tanzania Standard time of GMT+2:30 was adopted on 1913-10-01, then GMT+3 at midnight of 1925-05-16, GMT+2:45 on 1937-01-01 and GMT+3 on 1942-08-01. Popular Astronomy: A Review of Astronomy and Allied Sciences, Volume 22, p 328 https://books.google.com/books?id=yVFGAQAAMAAJ&pg=PA328 General Notice No. 335 of 1925, 1905-05-13, Tanganyika Gazette, Vol. VI No.20, 1925-05-15, p 175 Interpretation (Standard Time) Order in Council, 1929 (Government Notice No. 11), 1929-01-21, Supplement to the Tanganyika Territory Gazette, Vol. X, No.5, 1929-01-25, p 9 Interpretation (Standard Time) Order, 1936 (Government Notice No. 159), 1936-10-13, Ibid., Vol. XVII, No. 56, 1936-11-06, p 270 Interpretation (Standard Time) Order, 1942 (Government Notice No. 259), 1942-07-15, Ibid., Vol. XXIII, No. 36, 1942-07-24,p 296 https://1drv.ms/u/s!AgX5Bc6Y-VsIi2-tBj4iXt90KNrV?e=8yoy29 ----- Uganda At some point after 1905-11-08, Uganda time was 30 minutes behind Mombasa Mean Time. At some point before 1908-04-25, GMT+2:30 was adopted as the standard time. In 1937 and 1942, new standard times in Uganda were adopted simultaneously in Kenya and Tanganyika. Notice. Uganda Official Time., 1905-11-08, The Official Gazette of the East Africa and Uganda Protectorates, 1905-12-01, p 392 https://books.google.com/books?id=FsRZ7PcucTEC&pg=RA1-PA392 "Local Time.", East African Standard, Mombasa Times and Uganda Argus, 1907-11-23, p 16 http://ddsnext.crl.edu/titles/31664#?c=0&m=260&s=0&cv=15&r=0&xywh=1130%2C24… "Standard Time.",Ibid., 1908-04-25, p 17 http://ddsnext.crl.edu/titles/31664#?c=0&m=282&s=0&cv=16&r=0&xywh=3187%2C18… General Notice No. 601 of 1936, 1936-11-03, Official Gazette of the Uganda Protectorate, Vol. XXIX, No.25, 1936-11-16, p 385 General Notice No. 213 of 1942, 1942-07-11, The Uganda Gazette, Vol. XXXV, No. 14, 1942-07-15, p 102 https://1drv.ms/u/s!AgX5Bc6Y-VsIi3O5OxfZRvN46GWA?e=EbwRAe ----- Zimbabwe Standard time of GMT+2 was adopted in 1899-08-01. Before that, GMT+2:30 was used in Salisbury. The Bulawayo Chronicle, 1899-07-08, p 5 Government Notice No. 160 of 1899, 1899-07-20, The British South Africa Company Government Gazette, 1899-07-21, p 199 https://1drv.ms/u/s!AgX5Bc6Y-VsIi3Ruk-lLkymGZBUN?e=bJnSaL ----- Israel For the fallback transition in 1980, it could be either at 24:00 or 24:00s. sources with 24:00s: Maariv⁩, 1980-09-09, p 1 https://www.nli.org.il/en/newspapers/mar/1980/09/09/01/article/7 Davar,⁩ 1980-09-10, p 2 and 10 https://www.nli.org.il/en/newspapers/dav/1980/09/10/01/article/14 https://www.nli.org.il/en/newspapers/dav/1980/09/10/01/article/114.2 The Jerusalem Post, 1980-09-10, p 18 https://search.proquest.com/docview/918197263 source with 24:00: Maariv, 1980-09-10, p 12 https://www.nli.org.il/en/newspapers/mar/1980/09/10/01/article/83 sources with "midnight": Al-Ittihad⁩, 1980-09-12, p 8 https://www.nli.org.il/en/newspapers/?a=d&d=alittihad19800912-01&dliv=userc… The Jerusalem Post, 1980-09-10, p 1 and 1980-09-14, p 1 https://search.proquest.com/docview/918209000 https://search.proquest.com/docview/918188423 For the fallback transition in 1984, it should be at 24:00. Maariv, 1984-08-24, p 1 https://www.nli.org.il/en/newspapers/mar/1984/08/24/01/article/6 Al-Ittihad⁩, 1984-08-26, p 2 https://www.nli.org.il/en/newspapers/?a=d&d=alittihad19840826-01&dliv=userc… The Jerusalem Post, 1984-08-21, p 4 and 1984-08-24, p 1 https://search.proquest.com/docview/924823083 https://search.proquest.com/docview/924051659 The Jerusalem Post images: https://1drv.ms/u/s!AgX5Bc6Y-VsIjBGvgWp_o9PZfHyu?e=VmSRwW ------ Cyprus Before independence, DST was observed in 1940-1945 and 1948 List of Summer Time Orders: http://www.cylaw.org/cgi-bin/sinocgi.pl?title=summer+time&searchoption=1&di… An article on the government website said that DST in Cyprus was first implemented in 1976. https://cyineu.pio.gov.cy/%CE%B5%CF%80%CE%B9%CE%BA%CE%B1%CE%B9%CF%81%CF%8C%… List of decrees for DST since 1976: http://www.cylaw.org/cgi-bin/sinocgi.pl?title=%C8%E5%F1%E9%ED%DE%F2+%BF%F1%… Apparently, no decree was issued for DST in 1975 and 1977-1979. http://www.cylaw.org/KDP/1975.html http://www.cylaw.org/KDP/1977.html http://www.cylaw.org/KDP/1978.html http://www.cylaw.org/KDP/1979.html For other years, the rules in tz mostly match with the degrees, except: 1. spring forward transitions in 1994-1997 were at 00:01 instead of 00:00. 2. fallback transitions in 1996 and 1997 were at 24:00 of the last Saturday of October (or 00:00 of the last Sunday of October) instead of September. 3. EU rules were first used for the spring forward transition in 1998 instead of September 1998. The Sovereign Base Areas of Akrotiri and Dhekelia has similar DST rules as Cyprus. List of Summer Time Orders of the Sovereign Base Areas: 1976: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1980: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1981: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1982: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1983: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1984: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1985: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1986: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1987: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1988: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1989: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1990: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1991: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1992: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1993: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1994: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1995: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1996: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1997: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… 1998: https://sbaadministration.org/home/legislation/01_02_09_06_PIs/01_02_09_06_… (EU rules have been adopted since 1998) These orders were not publicly listed, some were searchable by search engine, the others were found by brute-force. Apparently, no order was issued for DST before 1976 and 1977-1979. These orders mostly correspond to the decrees of Cyprus, except the transition times were in GMT, which was not stated in the decrees of Cyprus prior to 1998. Also, spring forward transition in 1994 was 00:00 (GMT) instead of 00:01. ------ Shanghai Standard time of GMT+8 was adopted by the French concession at noon on 1903-01-01, before that GMT+8:05:56.7 (Shanghai mean time) was used. "A New Time for the New Year", The North China Herald and Supreme Court & Counsular Gazette, 1902-12-31, p 1383 https://search.proquest.com/docview/1369511715/ The Straits Times, 1903-01-09, p 5 https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes1903… Newspaper sources for DST observed in 1919 and 1940-1949: (These are taken from "全国报刊索引" https://www.cnbksy.com/ and "中國近代報刊" https://www.dhcdb.com.tw/SP/) https://1drv.ms/u/s!AgX5Bc6Y-VsIjBV8vf4qIDkPyE_7?e=LUQyIy The China Press 1919-04-13, p 26 1919-09-28, p 1 1940-05-31, p 1 1941-03-15, p 10 1941-11-02, p 2 1946-05-15, p 5 1946-10-01, p 2 1947-04-15, p 1 1947-09-21, p 5 1948-04-30, p 9 1948-09-30, p 1 1949-05-01, p 5 The North-China Daily News 1940-10-13, p 6 1949-06-01, p 1 The Shanghai Sunday Times 1942-02-01, p 4 The Shanghai Times 1942-10-23, p 5 Shun Pao (申報) 1945-08-28, p 2 The spring forward transitions in 1941 and 1942 should be at 24:00, the fallback transition in 1945 should be at 00:00. Actually these can also be deduced from Li Yu's article: footnote 29: 《沪市继续推行日光节约运动，自本月十五日午夜实行》，《申报》1941年3月12日，第7版。 footnote 34: 《日光节约时间昨夜开始》，《申报》1942年2月1日，第3版。 the sentence before footnote 37:"...宣布本年9月1日零时起结束'日光节约时间'" The communist city government ended DST at 00:00 on 1949-06-01. The rules for Shanghai and Taipei in 1946-1949 are the same. Maybe they can be merged. ------ Malaysia and Singapore Some of the sources mentioned in Aslaksen's webpage about Singapore time: Government Notification No. 1000, 1900-09-06, Straits Settlements Government Gazette, 1900-09-07, p 1933 https://eservice.nlb.gov.sg/data2/BookSG/publish/f/fe38abfe-bfbb-46f2-b977-… Government Notification No. 201, 1904-02-22, Ibid., 1904-02-26, p 300 https://eservice.nlb.gov.sg/data2/BookSG/publish/d/df4b34d6-7388-4c84-9b33-… Daylight Saving Ordinance, 1932 (No. 21 of 1932), Ibid., 1932-12-23, p 2623 https://eservice.nlb.gov.sg/data2/BookSG/publish/1/1d7e5694-43e5-46b2-b050-… Government Notification No. 2367, 1933-12-04, Ibid., 1933-12-15, p 2706 https://eservice.nlb.gov.sg/data2/BookSG/publish/9/91e94bfb-1e92-4451-badc-… Government Notification No. 2371, 1934-10-08, Ibid., 1934-10-19, p 2954 https://eservice.nlb.gov.sg/data2/BookSG/publish/d/d9d45030-bb72-4d5c-8a7e-… Daylight Saving (Amendment) Ordinance, 1935 (No. 5 of 1935), Ibid., 1935-03-08, p 488 https://eservice.nlb.gov.sg/data2/BookSG/publish/e/e16c3415-b038-48c8-90c2-… Daylight Saving Ordinance (Chapter 170), The laws of the Straits Settlements Edition of 1936, Vol VI, p 694 https://eservice.nlb.gov.sg/data2/BookSG/publish/b/b8f6f919-b64d-4ac5-ab10-… Daylight Saving (Amendment) Ordinance, 1941 (No. 33 of 1941), Supplement to the laws of the Straits Settlements, 1942, Vol I, p 223 https://eservice.nlb.gov.sg/data2/BookSG/publish/6/6f963fc2-9708-41c5-b7b2-… Daylight Saving Ordinance (Chapter 266), The laws of the Colony of Singapore Edition of 1955, Vol VII, p 319 https://eservice.nlb.gov.sg/data2/BookSG/publish/5/57ab953e-f062-40ea-aeda-… Interpretation and General Clauses Ordinance (Chapter 2), Ibid., Vol I, pp 17-38 https://eservice.nlb.gov.sg/data2/BookSG/publish/9/91034b99-bb5f-4ec6-b371-… Singapore Standard Time Notification (G.N. No. S 392/1981) https://sso.agc.gov.sg/SL/IA1965-N1/Historical/19920325?DocDate=20000831&Va… Malaysian Standard Time Act 1981 (Act 261) http://www.commonlii.org/my/legis/consol_act/msta1981223/ Other sources: "Malaya Finished With 'Tokyo Time'", The Straits Times, 1945-09-07, p 1 https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes1945… Statute Law Revision Bill (Bill No. 36/1970) https://sso.agc.gov.sg/Bills-Supp/36-1970/Published/19700728?DocDate=197007… With regard to Aslaksen and tz, the 1935 Ordinance, which made the Daylight Saving Ordinance permanent, was commenced on 1935-03-08. During WWII, Kuala Lumpur was occupied by Japanese a month earlier than Singapore. Kuching was also occupied earlier in December 1941. Therefore it is unlikely that they switched to GMT+9 on the same day. The Daylight Saving Ordinance was repealed by the Statute Law Revision Act 1970 (No. 48 of 1970). The 1981/1982 transition took place at 16:00 GMT on 1981-12-31. (This was actually mentioned by Mok Ly Yng but the entry has remained uncorrected since 2003.) Some of the sources for Sarawak: Order No. VIII, 1926, 1926-02-11 The Sarawak Government Gazette, 1926-02-16, Vol.19 No.433, p 54 https://books.google.com.hk/books?id=VKbL-mOu1F8C&pg=PA54 Notification No. 429, 1930-06-30 Ibid., 1930-07-01, Vol.23 No. 552, p 248 https://books.google.com/books?id=B5saIO8yLL0C&pg=RA4-PA14 Notification No. 436, 1931-06-24 Ibid., 1931-07-01, Vol.24 No. 579 p.193 https://books.google.com/books?id=YqvrMnxJHAYC&pg=RA16-PP3 Notification No. 798, 1931-12-03 Ibid., 1932-01-02, Vol.24 No. 591, p 356 https://books.google.com/books?id=YqvrMnxJHAYC&pg=RA30-PA10 Notification No. 1274, 1940-09-06 Ibid., 1940-09-16, Vol.33 No.38, p 701 https://books.google.com/books?id=HDU3vTSR4UYC&pg=PA701 Defence (Standard Time (revocation)) Regulations, 1946 Ibid., Vol. 1 No.4, 1946-08-16, p 48 https://books.google.com/books?id=pWd9qBTe4gYC&pg=PA48 Standard Time Ordinance, 1946 (No. 2 of 1946) Ibid., Vol. 1 No.20, 1946-12-16, p 232 https://books.google.com/books?id=pWd9qBTe4gYC&pg=PA232 Standard Time Regulations, 1950 Colony of Sarawak Supplement to the Government Gazette, Sup. No. 6, 1950-04-17, p 50 https://books.google.com/books?id=GelAgpgyMpUC&pg=RA1-PA50 Standard Time (Amendment) Ordinance, 1950 (No. 2 of 1950) Ibid., Sup. No. 12, 1950-05-30, p 91 https://books.google.com/books?id=GelAgpgyMpUC&pg=RA1-PA91 "Sarawak Standard Time", The Sarawak Gazette, 1926-03-01, p 55 https://www.pustaka-sarawak.com/gazette/gazette_uploaded/1370908367.pdf#pag… "Mainly About Nothing", Ibid., 1929-12-02, p 213 https://www.pustaka-sarawak.com/gazette/gazette_uploaded/1399273124.pdf#pag… "Time in Sarawak", Ibid, 1932-10-01, p 168 https://www.pustaka-sarawak.com/gazette/gazette_uploaded/1399277620.pdf#pag… "Sarawak Chronology", Ibid, 1961-07-31, p 131 https://www.pustaka-sarawak.com/gazette/gazette_uploaded/1403144292.pdf#pag… "Summer Time in Sarawak" ,The Straits Times, 1932-09-29, p 19 https://eresources.nlb.gov.sg/newspapers/Digitised/Article/straitstimes1932… The Sarawak Government Gazette, 1929 https://books.google.com/books?id=wmtR6OfLitQC The Sarawak Government Gazette, 1941 https://books.google.com/books?id=sTOu9S62f9IC Standard time of GMT+7:30 was adopted in Sarawak on 1926-03-01. DST was officially observed in 1930-1939, GMT+7:50 was used from September to December. The 1933 transition in tz should be an error. According to some sources, DST was also observed in 1929, but the details are unclear. It was not mentioned in the Government Gazette issues published in 1929. According to the Defence (Standard Time (revocation)) Regulations, 1946, the Defence (Standard Time) Regulations, 1941 suspended the 1926 Order. But the text of the 1941 Regulations is unknown. The 1941 issues of Government Gazette on Google Books are only up to 1941-12-09. Therefore it is likely that those regulations were publish after that day. The 1946 Regulations reinstated the 1926 Order but did not affect the clock. The time zone being used during 1945-1946 is unclear. Standard time of GMT+8 has been adopted since 1950-05-01. "NBorneo" do not seem to be an appropriate name for the rules for Sarawak (Asia/Kuching). Since "North Borneo" usually refers to the territory which is now Sabah.

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Temporal - ECMAScript built-in JS Library for dates/times/timezones/calendars in progress
by Jase Williams March 8, 2021

March 8, 2021

Hi I'm one of the TC39 (EcmaScript) delegates. As a heads up to anyone interested, we're creating a new built-in module in JavaScript (to hopefully replace Date()) called Temporal. This new, rich API includes: - First-class support for all time zones, including DST-safe arithmetic - Strongly-typed objects for dates, times, date/time values, year/month values, month/year values, "zoned" date/time values, and durations - Immutability for all Temporal objects - String serialization and interoperability via standardized formats - Compliance with industry standards like ISO 8601, RFC 3339, and RFC5545 (iCalendar) - Full support for non-Gregorian calendars Feel free to play around with it and offer feedback on the repo. The repository is here: https://github.com/tc39/proposal-temporal Documentation here: https://tc39.es/proposal-temporal/docs/index.html Polyfill here: https://github.com/tc39/proposal-temporal/tree/main/polyfill EcmaScript spec: https://tc39.es/proposal-temporal/ It's currently Stage 2 which means it's under review, but there's hope to see this implemented in Browsers/NodeJS soon. For consideration in tz-link.html. Feel free to adjust wording Project: https://github.com/tc39/proposal-temporal NPM: https://www.npmjs.com/package/proposal-temporal Thanks Jason Williams

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