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Invalid tm handling in %s pattern in strftime
by Almaz Mingaleev June 7, 2022

June 7, 2022

Hi Paul, https://github.com/eggert/tz/commit/8b238ec54c09556eb2aa405c1741eedfd12c4a8… added validation of tm argument. I wonder why localtime_r call is done: 1) According to the man page mktime sets errno if tm is invalid. Why is it not safe to just check errno value (saving and restoring it if needed)? 2) man page says that in error case mktime "returns (time_t) -1 and does not alter the members of the broken-down time structure". Wouldn't it be enough to check that tm.tm_yday is >= 0? Thanks, Almaz

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Subject: Re: Change Turkey to Turkiye or not?
by nadir altinbas June 7, 2022

June 7, 2022

@ Topic 4. Re: Change Turkey to Turkiye or not? (Ian Abbott) i am resident in Istanbul, Istanbul is a city where a bridge of between Europe and Asia? most of the part of istanbul city is in Europe side. Telephony numbering coding system for PBX Europe is 0212 and Asia 0216 begins. Turkey -Turkiye- Turquie (Tr) name can be positined name as it Tr /Turkiye-Istanbul (Europe -Asia) ....... This is my idea. regards , nadir ALTINBAS nadiraltinbas(a)yahoo.com n.altinbas

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Change Turkey to Turkiye or not?
by 柳芯宇 June 7, 2022

June 7, 2022

In some of the tz files, I found several mentions of "Turkey", this could be confusing since in my dictionaries, Turkey points to a food made by chicken, rather than a country. As recently UN and NATO suggests, I think it would be better and more representative to use Turkiye instead of Turkey, as we shound't setup times for just foods, right?

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Re: [tz] Change Turkey to Turkiye or not?
by Doug Ewell June 6, 2022

June 6, 2022

柳芯宇 wrote: > In some of the tz files, I found several mentions of "Turkey", this > could be confusing since in my dictionaries, Turkey points to a food > made by chicken, rather than a country. I checked with a few turkeys (the bird) and they objected loudly to the notion that they are actually chickens. All joking aside: 1. The country has been known in English as "Turkey" for centuries, and although this has certainly given rise to some jokes, no one is genuinely confused when the word is used in context. 2. The identifier in the tz database which has by far the greatest visibility and relevance to users is "Europe/Istanbul", which avoids the issue altogether. 3. The rule name "Turkey" is comparatively invisible to most users, and there does not seem to be any mechanism for changing rule names, as there is for zone identifiers. 4. Any other mentions, such as in comments, can be changed freely, but there seems little point in doing so, at least at this time. > As recently UN and NATO suggests, I think it would be better and more > representative to use Turkiye instead of Turkey, as we shound't setup > times for just foods, right? "Turkiye" is not the name of the country in any language; the Turkish name is spelled "Türkiye" with diaeresis. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org

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Historical data for Iran
by Roozbeh Pournader June 6, 2022

June 6, 2022

Hi, The timezone database currently lists Iran switching to standard time in 1946. I've been doing some research on the history of the adoption of standard time by Iran, and while it's very hard to find much, I found that the correct date is actually 1935. Here's an order from the Cabinet to the rest of the government to switch to Tehran time, which is mentioned to be already at +03:30: https://qavanin.ir/Law/TreeText/180138 Just in case that goes away, I also saved a copy at archive.org: https://web.archive.org/web/20220530111940/https://qavanin.ir/Law/TreeText/… Here's my translation: "Circular on Matching the Hours of Governmental and Official Circles in Provinces Approved 1314/03/22 [=1935-06-13] According to the ruling of the Honorable Cabinet, it is ordered that from now on in all internal provinces of the country, governmental and official circles set their time to match Tehran time (three hours and half before Greenwich). It is required to mind the above order. For Minister of Judiciary, Dr Matin-Daftari" Now, I still haven't found out when Tehran itself switched to +03:30 (let's assume some time earlier in 1935), but it is clear that standard time in Iran started on 1935-06-13 and not 1946. Thanks, Roozbeh

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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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