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Yet more historical data for Iran
by Roozbeh Pournader June 2, 2022

June 2, 2022

Yet another discovery, which clarifies what happened in 1977 and 1978 in Iran. This is from Kayhan newspaper, one of the major Iranian newspapers, from March 20, 1978, page 2: "Pull the clocks 60 minutes forward As we informed before, from the fourth day of the month Farvardin of the new year [=1978-03-24], clocks will be pulled forward, and people's daily work and life program will start one hour earlier than the current program. On the 1st day of the month Farvardin of this year [=1977-03-21], they had pulled the clocks forward by one hour, but in the month of Mehr [=1977-09-23], the clocks were pulled back by 30 minutes. In this way, from the 4th day of the month Farvardin, clocks will be ahead of the previous years by one hour and a half. According to the new program, during the night of 4th of Farvardin, when the midnight, meaning 24 o'clock is announced, the hands of the clock must be pulled forward by one hour and thus consider midnight 1 o'clock in the forenoon." This implies that in September 1977, when the daylight savings time was done with, Iran didn't go back to +03:30, but immediately to +04:00. I'm still trying to figure out when exactly did Iran go back from +4:00 to +03:30. I'll report back when I find it. Based on the time of true noon announced in newspapers of the time, I've triangulated it to some time between 1978-11-05 and 1979-01-15, but it looks like major Iranian newspapers were stopped from publishing during most of that time period, so I can't figure out more using this method. For now, two changes are needed in tzdata, first is the start of daylight saving in 1978, the other the switch to +4:00/+5:00, which is currently listed as Nov 1977, but should change to exactly the end of daylight saving time in 1977. Thanks again, Roozbeh

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End date of daylight saving in Iran in 1978
by Roozbeh Pournader June 1, 2022

June 1, 2022

I just found the date daylight savings ended in Iran in 1978. This is from the major Iranian newspaper Ettela'at, dated 1968-08-03, page 32. It looks like they decided to get the clocks back to +4:00 just in time for Ramadan that year: "Tomorrow Night, Pull the Clocks Back by One Hour At 1 o'clock in the forenoon of Saturday 14 Mordad [=1978-08-05], the clocks will be pulled one hour back and instead of 1 o'clock in the forenoon, Radio Iran will announce 24 o'clock. This decision was made in the Cabinet of Ministers meeting of 25 Tir [=1978-07-16], [...] At the beginning of the year 2537 [=March 1978: Iran was using a different year number for a few years then, based on the Coronation of Cyrus the Great], the country's official time was pulled forward by one hour and now the official time is one hour and a half ahead compared to last year, because in Farvardin of last year [=March 1977], the official time was pulled forward one hour and this continued until the second half of last year [=September 1977] until in the second half of last year the official time was pulled back half an hour and that half hour still remains." This matches the time of the true noon published in the newspapers, as they clearly go from +05:00 to +04:00 after that date (which happened during a long weekend in Iran). This means tzdata needs to fix the end of daylight saving in Iran for 1978 from October 20 to August 5. Thanks again, Roozbeh

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Wrong behaviour with truncated TZif files
by Almaz Mingaleev June 1, 2022

June 1, 2022

Hi Paul, I've built TZif files with following commands: mkdir /tmp/zic cd /tmp/zic git clone https://github.com/eggert/tz.git . make -C . zic make -C . NDATA= rearguard.zi mkdir data # Truncate at 1 Jan 2100. ./zic -b fat -r "/@4102444800" -d ./data rearguard.zi make TZDIR="./data" all Then I've compiled attached file: g++ mktime_test.cpp localtime.o Test tries to find epoch timestamp for 2 Jul 1980 midnight at America/Los_Angeles. With a truncated TZif file it prints 331344000. With non-truncated one it prints 331372800. The latter is the right answer. Also, date command is wrong on certain time zones: make TZDIR="./data" date TZ=Antarctica/Palmer ./date -r -631152000 prints "Sat Dec 31 20:00:00 -04 1949" even though 1 Jan 1950 offset should be zero <https://github.com/eggert/tz/blob/df4699ddfc9caf6f875f1e38703dd0ef41826175/…> . Thanks, Almaz

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More historical data for Iran
by Roozbeh Pournader June 1, 2022

June 1, 2022

Two more pieces of information about historical timezone changes in Iran, this time in the late 1970s: I just ran into an academic paper that looks into the psychology of daylight savings in Iran, and it has the exact times for the change in 1977 and the beginning of the change in 1979 (but not its end, unfortunately). https://www.jstor.org/stable/178704 Here's the quotes from the paper: 1. '"Iran's official time keeper moved the clock one hour forward as from March 22, 1977 (Farvardin 2, 2536) to make maximum use of daylight and save in energy consumption. Thus Iran joined such other countries as Britain in observing what is known as 'daylight saving.' The proposal was originally put forward by the Ministry of Energy, in no way having any influence on observing religious ceremonies. Moving time one hour forward in summer means that at 11:00 o'clock on March 21, the official time was set as midnight March 22. Then September 24 will actually begin one hour later than the end of September 23 [...]." Iran's time base thus continued to be Greenwich Mean Time plus three and one-half hours (plus four and one-half hours in summer).' The article sources this from Iran Almanac and Book of Facts, 1977, Tehran: Echo of Iran, which is on Google Books at https://www.google.com/books/edition/Iran_Almanac_and_Book_of_Facts/9ybVAAA…. (I confirmed it by searching for snippets.) 2. "After the fall of the shah, the revolutionary government returned to daylight-saving time (DST) on 26 May 1979." This seems to have been announced just one day in advance, on 25 May 1979. The change in 1977 clearly seems to be the first daylight savings effort in Iran. But the article doesn't mention what happened in 1978 (which was still during the shah's government), or how things continued in 1979 onwards (which was during the Islamic Republic). This data doesn't seem to match tzdata: First, an entry for 1977 needs to be added, for which we seem to have complete data. Second, the beginning of daylight saving time in 1979 needs to be changed to May 26. Thanks, Roozbeh

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Re: [tz] Kiev -> Kyiv
by Doug Ewell May 31, 2022

May 31, 2022

Jacob Pratt wrote: >> I know you are all busy, but you made a mistake in the timezone name. >> Just want to make a request to change "Kiev" to "Kyiv". > > This change has already been made. People keep asking for this because the currently released version of the tz database (2022a) still has "Europe/Kiev". The fact that the change to "Europe/Kyiv" is in the GitHub development repo, and will eventually make its way to a released version, is not helpful to these people. They want to see it in a release. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org

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Kiev -> Kyiv
by Roman Dmytriv May 30, 2022

May 30, 2022

Hello IANA team! "After Ukraine's 1991 independence, the Ukrainian government introduced the national rules for transliteration of geographic names <https://en.wikipedia.org/wiki/Romanization_of_Ukrainian> into the Latin alphabet for legislative and official acts in October 1995,[23] <https://en.wikipedia.org/wiki/Name_of_Kyiv#cite_note-:1-23> according to which the Ukrainian name Київ is romanized <https://en.wikipedia.org/wiki/Romanization> as *Kyiv*. These rules are applied for place names and addresses, as well as personal names in passports, street signs, and so on." I know you are all busy, but you made a mistake in the timezone name. Just want to make a request to change "Kiev" to "Kyiv". I will be grateful for the answer. Thank you! Best regards, Roman Dmytriv tel: +380633709302

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Change some timezone names
by gusak ivanov May 27, 2022

May 27, 2022

Good evening! I’ve read some great news, that you are finally changing Europe/Kiev to Europe/Kyiv. Can other Ukrainian timezones get the same treatment, and so get Europe/Uzhgorod to be changed to Europe/Uzhhorod and Europe/Zaporozhye to Europe/Zaporizhzhia? All according to the officially recognized UNGEGN World Geographical Names. Thanks

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Duplicated shell commands on the tz-link.html IANA page
by Max Nikulin May 25, 2022

May 25, 2022

Hi, Some time ago I have noticed that shell commands are duplicated in the "Downloading the tz database" section on the following page https://data.iana.org/time-zones/tz-link.html#download > mkdir tzdb > cd tzdb > wget https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz > wget https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz > gzip -dc tzcode-latest.tar.gz | tar -xf - > gzip -dc tzdata-latest.tar.gz | tar -xf - I think it is better to remove some commands.

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Unexpected last transition in Africa/Casablanca
by Almaz Mingaleev May 19, 2022

May 19, 2022

Hi Paul, Here are the last transitions in Africa/Casablanca output (rearguard format): transition,type,[UTC time],[Type offset],[Type isDST] 3672612000,1,2086-05-19T02:00:00Z,PT1H,DST 3699828000,2,2087-03-30T02:00:00Z,PT0S,STD 3703456800,3,2087-05-11T02:00:00Z,PT1H,STD So change is from standard to standard, even though offset changes from 0h to 1h. Is that expected behaviour? As Africa/El_Aaiun is using Morocco rules, its transitions are also affected. This affects 64-bit section only, 32-bit section looks fine to me. Thanks, Almaz Data above is output of debug tools used in Android. The way I've built data an byte manipulations if needed: mkdir /tmp/zic cd /tmp/zic git clone https://github.com/eggert/tz.git . make -C . zic make -C . NDATA= rearguard.zi mkdir data ./zic -b fat -d ./data rearguard.zi byte manipulations: Let's skip 32-bit header: xxd -seek 20 -c 4 -l 24 data/Africa/Casablanca typecnt: 94 timecnt: 5 charcnt: 12 32-bit block size = 94 * 4 + 94 + 5 * 6 + 12 = 512 64-bit start = 44 + 512 = 556 64-bit header: xxd -seek 576 -c 4 -l 24 data/Africa/Casablanca: timecnt: 196 typecnt: 4 <- 32-bit section has 5 charcnt: 12 transition types offset: 556 + 44 + 196 * 8 = 2168 xxd -seek 2168 -c 1 -l 196 data/Africa/Casablanca ... 00000934: 02 . 00000935: 01 . 00000936: 02 . 00000937: 01 . 00000938: 02 . 00000939: 01 . 0000093a: 02 . 0000093b: 03 . <- the last transition local time records offset = 556 + 44 + 196 * 9 = 2364 xxd -seek 2364 -c 6 -l 24 data/Africa/Casablanca 0000093c: ffff f8e4 0000 ...... 00000942: 0000 0e10 0104 ...... 00000948: 0000 0000 0008 ...... <- standard time 0000094e: 0000 0e10 0004 ...... <- also standard time

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Change IANA time zone identifier for Kyiv to Europe/Kyiv.
by Luda Melnykova May 19, 2022

May 19, 2022

Hello, Hope this email finds you well. I would like to raise a request for a value change in TZ DB. I believe, that current IANA time zone identifier for Kyiv (Europe/K*ie*v) is not fully correct. Background of this request lies in a transliteration of a city name. *Kyiv* is derived from the Ukrainian language name Київ, while *Kiev* is derived from the Russian language name Киев) as the name of the Ukrainian capital. Kyiv is already in use in international lists for IATA, ICAO and other organizations, which follow the decision of the U.S. Board on Geographic Names. Kyiv, as a name of Ukrainian capital, is also mentioned on time.is site Kyiv: 19:42 (time.is) <https://time.is/Kyiv>. So, I believe, it is fully logical to follow latest guidelines and rename IANA time zone identifier as well. If you are interested to learn more about it, please check out this wiki article: KyivNotKiev - Wikipedia <https://en.wikipedia.org/wiki/KyivNotKiev> Please let me know if any questions or concerns. Many thanks. Regards, Liudmyla

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