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Typo in zic(8) man page
by Jonathan Wakely Oct. 8, 2021

Oct. 8, 2021

The description of a RULES field in a zone line says: "giving of the amount of time to be added" The first "of" looks like a typo.

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Classifying IDs
by Stephen Colebourne Oct. 8, 2021

Oct. 8, 2021

Following on from the previous thread [1] I wanted to try and classify the IDs we have, which may or may not identify missing IDs. Again, please avoid talking about pre-1970 data at this point. Obsolete ------------ IDs that are obsolete and should never be used. They date from many years ago whe tzdb was just starting. Yet these still do appear in downstream UIs even today (of course UIs should not use the tzdb ID list, but in reality lots do). Examples: Portugal, NZ-CHAT, Navajo, Libya. Proposal: Provide 3-6 months notice, then move obsolete IDs to a new file "obsolete" which downstream projects are strongly encouraged not to include. (I would argue that the time has come to properly remove these IDs, which are very inconsistent in terms of which are provided and which not, eg Portugal, but not Spain) Deprecated, same location ------------------------------------ IDs that have been deprecated with a single clear alternative ID being provided. Both IDs represent the same physical location/city. Spelling changes: Asia/Katmandu (replaced by Asia/Kathmandu), Asia/Rangoon (replaced by Asia/Yangon) ID structure changes: America/Louisville (replaced by America/Kentucky/Louisville) Proposal: Ensure all of these are in `backward` Consider: Is there any way to move these IDs to the obsolete file? Maybe after 5 years? Or do we just accept backwards compatibility restrictions on these? Legally described mega-zones ----------------------------------------- IDs for locations where a federal or supra-national body defines rules, eg the EU or US DOT. Examples: US/Mountain, CET, WET Consider: Can we write down a rule to identify when something like this should be included? Then move the matching IDs to the main files (eg. are the EU and US DOT the only two examples here?) Regions ----------- IDs for abstract regions that have had the same wall clock since 1970. Examples: Europe/Berlin, America/New_York, Africa/Abidjan Proposal: Ensure all of these are in the main files. Consider: Should there be new IDs for each of these abstract regions to indicate they are a separate and distinct concept? eg. "Region/Berlin". (Maybe something to consider in future threads as it isn't clear what the benefit of doing so is without considering pre-1970 which I'm still trying to avoid) Non-region locations --------------------------- IDs for locations that are not region IDs. Each ID will have the same wall clock since 1970 as one of the region IDs. Examples: Europe/Oslo, Europe/Amsterdam, Atlantic/Reykjavik Consider: Can we write down a rule that covers which IDs are included here? And therefore when a new ID can be added to this set? If we can define a rule, then these can be split so rule-following IDs are in the main files and rule-breaking ones are in `backward` (although ideally they should be separate from the spelling changes). Obviously, we can say these IDs only exist for backwards compatibility, but that seems like a weak justification, and doesn't tackle the issue of when a new ID would be added to the list (which has been a point of tension). As is well known, I think the obvious rule is that the IDs follow the ISO-3166-1 standard (rule: one ID per ISO code, additional IDs may be added where clocks have diverged since 1970). Using ISO-3166 can be justified by IANA domain policy [2]: "We are not in the business of deciding what is and what is not a country. Instead, we employ a neutral standard maintained by the ISO 3166 Maintenance Agency. Our policy is to create new country-code top-level domains when the country or territory is listed on the ISO 3166-1 standard." As per the previous thread, these non-region location IDs are actively used in downstream business applications, and it is not OK that only works because tzdb happens to have IDs for backwards compatibility. There needs to be a better justification than that - these non-region locations need to be fully supported, with a consistent rule used to define what is and is not fully supported. Fixed/etc type rules -------------------------- IDs with a fixed offset Examples: GMT, UTC, Etc/GMT-9 Proposal: No change, retain in the main files unless a particular ID is considered obsolete or deprecated Are there any more classifications I've missed? Stephen [1] https://mm.icann.org/pipermail/tz/2021-September/030857.html [2] https://www.iana.org/help/eligible-tlds

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Downstream use of 2021c
by Philip Paeps Oct. 8, 2021

Oct. 8, 2021

Since the tzdata 2021c release removed most of the controversial link changes, I wonder how other downstreams feel about importing it. I spent some time this morning looking at the downstreams I know about. FreeBSD has 2021c in main but is still on 2021a plus Samoa and Jordan in the supported stable branches. Debian is in the same state as FreeBSD. NetBSD, OpenBSD and Ubuntu are on 2021a + Samoa and Jordan. Fedora is on 2021b. CentOS is on 2021a. A casual glance at other Linux distributions shows they are either on 2021a or 2021c. I am not familiar with their support models so I can't read anything into that. Python "pytz" seems to be on 2021c. Python "tzdata" seems to be in a similar state to FreeBSD, though I'm not sure I'm interpreting the release model correctly. I know Paul G is on this mailing list though. As far as I can tell, PostgreSQL is still on 2021a without modifications for Samoa and Jordan. Tom will correct me if I'm reading that wrong. I don't know enough about PHP, Java or any of the other well-known (let alone less well-known) downstreams to figure out what they're doing. This is looking terribly fragmented. Spare a thought for a hypothetical engineer tasked with debugging a Java application on Debian with some Python scripts on Fedora talking to a PostgreSQL database running on FreeBSD... While discussions on this list appear to have become more constructive, it looks like we're still lacking a clear consensus on the long-term direction. I feel that 2021c is a pretty reasonable compromise and would be willing to merge it to the supported FreeBSD releases. Is this something other downstreams would consider too? Alternatively, can we reach an interim consensus for a 2021d release that we'd all be willing to merge? Philip -- Philip Paeps Senior Reality Engineer Alternative Enterprises

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Use cases for source data
by Gilmore Davidson Oct. 8, 2021

Oct. 8, 2021

Stephen Colebourne's recent attempts to define requirements and use cases for tzdb got me thinking about the source data files. There have been several discussions over the years regarding the intended stability of the source format, separate from TZif binary files. These generally arise when the answer to a data query is "use this special compile-time flag". The most recent example is from Stephen at http://mm.icann.org/pipermail/tz/2021-September/030561.html The subtlety is in how the data set is consumed. While many downstream > projects use the makefile, not all do. A significant portion of > downstream users make use of the source files directly, with their own > parsers. ie. there is no ability to use a compile-time option. Those > parsers are not setup to use backzone even if it were a valid option > I think some of these discussions come about because there's disagreement about the intended use of the source files. The impression I've got from this list over the years is that the source files weren't intended to be a stable API; only the compiled TZif binary files were intended to be consumed downstream (and in later years, the .zi text representations). But many projects do use the source files as their primary interface, leading to tension when the format changes. So this is my attempt to list the use cases that people have for the source data files. This could prompt a wider discussion about what counts as a defined, stable interface for tzdb. Not every consumer of tzdb data is relying solely on the pre-compiled binary files. NOTE: This is a separate issue from the recent pre-/post-1970 data discussions. I'm trying to stay away from wading into that topic. ----------------------- Consumers of the source data text files: 1) The zic compiler for producing TZif binary files and .zi text files in an official tzdb release. 2) People reading the file comments to understand the history of certain zones. 3) Libraries/projects that need to parse/compile the data into a different representation than that provided by zic. This is often, but not exclusively, to preserve the distinction between Link and Zone entries, either for API or data compression reasons. 4) Data analysis or visualisations that care about knowing the higher-level Rule definitions ("transition on the last Sunday of October every year") rather than the exact transition timestamps for each year. 5) IDE or text editor plugins that provide syntax highlighting for the source files. All of these are based just on my own experiences and from lurking on this list. Any corrections/additions are welcome.

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Re: [tz] On ISO country for timezones (Re: Classifying IDs)
by dpatte Oct. 7, 2021

Oct. 7, 2021

I believe you are missing an important part of this discussion.There is a strong need for a repository of pre 1970 data, especially for historical research applications. As this is the only tz database, tz has also become the main database for this older data.For any populated place on earth researchers need such a repository. If I want to add the pre 1970 tz history for Ottawa Canada where should it be stored? Since it is called tz, and it also has other pre 1970 data, tz seems the appropriate place.But if no simple method of adding open-ended historical data is negotiated here, then the only other option is to fork tz and work on it as a separate project.Secondly, since the number of locations that could eventually be supported in a historical tz database is potentially very large, it cannot not be micromanaged, and this suggests that each historical zone should use an international standard for naming - iso - for simplicity and clarity.Canada/Ontario/OttawaAre we going to have two tz databases, or just one. That is the question here.Sent from my Galaxy -------- Original message --------From: Steffen Nurpmeso via tz <tz(a)iana.org> Date: 2021-10-07 09:35 (GMT-05:00) To: Stephen Colebourne <scolebourne(a)joda.org> Cc: tz(a)iana.org Subject: Re: [tz] On ISO country for timezones (Re: Classifying IDs) Stephen Colebourne wrote in <CACzrW9Cau-q2e+yoBcg=7Rztu19zZN582Xca9ZMYbz=H_0iOpw(a)mail.gmail.com>: |On Thu, 7 Oct 2021 at 07:08, Watson Ladd via tz <tz(a)iana.org> wrote: ... |I agree with backwards compatibility. The primary concern here is |whether an ID is considered deprecated or not.IDs shall be stable and not change at all. At maximum they shouldbe moved to backward, for example if a zone is renamed (which mayhappen for example for Ukraine in a not too distant future, ifthat is still necessary then, and it looks as if it would be).I would always have been all for making infinite stability of IDsa documented assertion.Even if not, your "six months" claim is nothing but an aggressivestatement. I think this entire thread is shadowboxing and noisefor nothing.Looking at the interface of your JAVA framework i think getID()should simply return the correct ID, which may be a link if it isone, and just in case this is not what getID() already returns.In my opinion there are only two problems with IANA TZ and howPaul Eggert manages it as a maintainer. That is the same PaulEggert who contributes to this software since 1995, an astonishing26 years. Corroding the maintainership with a continuous streamof noise is disgusting.The first is combining of datasets to equal-post-1970 bundles,which is going on for many years. But the data is there, it is inbackzone, and everybody can easily install a complete TZ DB onone's own request. Yet noone did, even though many packagers areon this list. This is schizophrenic. But maybe it is onlybecause of black and yellow people do not matter as much as someblue-eyed white people from northern Europe, which does not trulycome as a surprise given the audience who possibly reads this now,and given the fact that colonianisation ended only about 55 yearsago, and de facto was only turned from armed political to armedmaterial oppression.The second is that documentation did not follow suit the codeimprovements, as has been recently shown for tzselect(8) and the-t option. That tzselect(8) uses the administrative zone1970.taband not the end-user-preferrable zone.tab is a different thing.If you want to enforce upon the maintainer of the TZ database thatthe pre-1970 data is joined back into the normal data, or that"backzone" is splitted into "backzone" and "unreliable", and/orthat "backzone" is included by default, and/or that "ZFLAGS='-r@0'" is made default, then create a thread and try to gain enoughhums, but please stop this subversion by spreading uncertainty andthat even upon topics which never were under discussion as far asi know, and i also read this list for a decade now.It must anyway be said it was nicer once i only had thedistribution and did not know about the list :)Ciao from Germany,--steffen||Der Kragenbaer, The moon bear,|der holt sich munter he cheerfully and one by one|einen nach dem anderen runter wa.ks himself off|(By Robert Gernhardt)

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TZDB use cases
by Stephen Colebourne Oct. 7, 2021

Oct. 7, 2021

In this thread I want to try and capture the *requirements* for the project from the perspective of a downstream user. Given this, we may then have a chance to analyse whether the project needs a change of rules. NOTE: The discussion below is not a proposal, nor does it seek to explore which locations get pre-1970 data. Lets keep that for another thread. -------- 1) "What is the time now?" To answer this question you need a dataset that records the current timezone rules for each region in the world. Over time that data will naturally build up to form a historic record. To aid the project, a 1970 rule has been adopted for data management. In some parts of the world, clocks have agreed since 1970 across large parts of a continent. In other parts of the world, different parts of the same country have had different rules since 1970. Viewing the data through a post-1970 lens splits the planet into regions where clocks have agreed since 1970. Some of these regions are quite abstract, for example the region including Iceland, Ivory Coast, and St Helena. An abstract region would need to be split if one of the parts of the region changed its timezone rules. If a user had previously selected to follow one of these abstract regions, they might have to change their timezone settings. For example, if a user in Iceland selected their abstract region by the recommended ID based on the largest city they would get `Africa/Abidjan`, but if the Ivory Coast changed their rules, users in Iceland would have to change their selected timezone. The minimum set of IDs is one ID for each abstract region. The current ID scheme selects the largest city in the abstract region. My interpretation: * An abstract region should theoretically have an ID separate to the IDs of the cities/countries in the region * Trying the ID of the abstract region to the largest city in the region is prone to failure if that city changes timezone rules but the rest of the abstract region stays the same. * An abstract region ID would naturally have no pre-1970 data, as it doesn't define data in a single city/location. * The alternative is to encourage users to use their local city, which means that IDs like Europe/Amsterdam and Europe/Oslo cannot be deprecated -------- 2) "What was the time at some instant in the past?" The project can answer this question pretty reliably for dates from 1970 onwards because of the data set in #1. The project can never realistically answer the question reliably or accurately before 1970 for *all* locations. For example, timezone rules were entirely local in the US for about 20 years, meaning that hundreds of entries would be needed to correctly capture the data. In addition, much of the historic data globally is unknown and not viable to research, even if someone wanted to do so. It is possible to research and record historic timezone rules for *some* locations. Europe/London being one example. The project generally operates on the basis that if an ID exists, historical data can be recorded against it, although which file that data lives in has varied over time. IDs are generally not created solely to document historic data. There is no minimum set of IDs for this use case - the set of possible IDs is unbounded. My interpretation: * The majority of pre-1970 data isn't much use * Some pre-1970 data is high quality, and almost certainly relied upon (eg Europe/London) * Without a massive increase in scope the best that can be done pre-1970 is to record data against IDs created for some other reason. -------- 3) "An event will happen at this time in the future" If an end-user wants to store an event in the future, eg. a one hour meeting next month, the correct approach is to store the date, time and zone ID, not the offset (which is not yet known for certain).Even if the local timezone authority changes the tz rules between now and the event, the time of the event is still correct. https://stackoverflow.com/questions/19166995/java-calendar-date-and-time-ma… For this approach to work, the ID that is stored must be aligned with the timezone authority. Business contracts are frequently written to describe future events. For example, payment must be made by 2pm Paris time on a given date. The minimum set of IDs for this use case is one ID per timezone authority. This is typically the country but not necessarily, examples being decisions devolved to states/nations etc. My interpretation: * Using TZDB IDs for future events/contracts is very widespread * In most parts of the world, this requires one ID per country, in some parts of the world additional IDs would ideally be needed such as per state in the US * One ID for each ISO country (as was the guideline in the past) is a reasonable minimum expectation of end users * While one might argue IDs for future events are not TZDBs problem, I believe the reality is that they are because usage in this way is already very widespread -------- 4) "An event will happen at this time in the future relative to a shared/common definition" Some future events are declared relative to a definition that is supra-national or federal. For example, US Mountain, US Pacific, EU Central etc. A TV show might be defined to air at 8pm Mountain Time in one months time. It will air at that time regardless of whether any of the states that are currently on Mountain Time change to Pacific Time. For example, even if Denver (and Colorado) moved to Pacific Time or stopped following DST, Mountain Time would still exist and the TV show would still air at 8pm Mountain. The minimum set of IDs for this use case is one ID per shared/common definition. These IDs are not full aliases for a country or city ID, although they may currently share data. To support this use case, these IDs cannot be deprecated. My interpretation: * Some shared zone IDs are distinct and separate enough to warrant a full ID * US Mountain time is not the same as Denver time when considering the future, the IDs could diverge * In TZDB terms, the Link from US/Mountain to America/Denver is fine to define the data, but US/Mountain should not be considered deprecated as it has a real and distinct meaning separate from America/Denver * It would be useful to agree what the criteria for including these shared/federal rules is. -------- 5) "Data should be backwards compatible" The project has various associated downstream projects. Many of these have an expectation of backwards compatibility. This compatibility extends to the binary format, the source format, and the data contained within. This use case wants to see the project just continue with the data it has, enhancing it over time. The project has a pretty good record in terms of not removing IDs. For example, IDs exist for "Portugal" and "Poland", but not "Italy" or "Spain" simply because they were defined once upon a time. My understanding is that IDs in the `backward` file represent deprecated IDs that should not be used going forward. Yet, downstream projects focussed on backwards compatibility will generally use the `backward` file in full. The minimum set of IDs for this use case is the set of IDs that existed in the previous release. My interpretation: * Many users care about compatibility * The current IDs are not going away * Inconsistency has existed in TZDB for many years, see "Portugal" vs "Spain" - no one wants to fix that * It is hard at present to identify IDs that are deprecated because of proper aliasing, such as spelling changes, vs those where the ID is a real location but its TZDB status has been reduced. * Change may be possible with a long notice period --------- Please note that the above is not a proposal, but an exploration of the design space. If you have any use cases I've missed feel free to write them up. thanks Stephen

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timezone Verschlimmbesserung
by Tony Finch Oct. 6, 2021

Oct. 6, 2021

Paul Eggert's rationale is informative https://mm.icann.org/pipermail/tz/2021-September/030764.html But I think there are a few more things to say. The aim of merging timezones was to avoid political issues and to reduce the maintenance burden. It seems to me that it has failed to achieve those goals. There have been several very long discussions on the topic, and the recent arguments are making exactly the same points as were made in 2013. So I think the changes have increased the amount of political discussion and controversy on the tz list, not reduced it. https://mm.icann.org/pipermail/tz/2013-May/thread.html https://mm.icann.org/pipermail/tz/2013-August/thread.html https://mm.icann.org/pipermail/tz/2013-September/thread.html Paul says in his rationale that it was a lot of extra work, and in other messages he said that he has found it hard to keep up with the discussions. So merging timezones has increased the maintenance burden, not reduced it. I have identified two policy changes that caused this argument. In 2013, Paul Eggert started a new policy of merging timezones that are the same since 1970. As far as I can tell, no-one wanted this other than Paul. This merging policy was applied first to places with small populations, and (because of alphabetical order) to Africa, which is not well-represented by the people on the TZ list. Some of the merges also ignored the guideline that each country should have at least one timezone to call its own. The other policy change was to drop the guideline that each country should have at least one timezone. This change occurred in 2019, buried at the end of a very long discussion about Vietnam, and presented as a fait accompli. https://mm.icann.org/pipermail/tz/2019-February/027602.html This was after a great deal of discussion about the need to retain country information in the tz database, back in 2013 when these changes started. As I understand it, the equity / fairness issue is that the timezone merges were implemented in an unfair manner, affecting Africa (since 2014, against the guidelines as written at the time) but not Europe. So although Paul says the merges worked without significant incident, they did in fact cause a political complaint - exactly what the merges were supposed to avoid. The current argument was triggered by the question of whether this fairness issue should be addressed by undoing the data loss in the compiled tz files that caused the complaint, or by imposing the data loss more strictly. I think the way to fix this is to revert both policy changes, and revert all the timezone merges. Tony. -- f.anthony.n.finch <dot(a)dotat.at> https://dotat.at/ Lundy, Fastnet, Irish Sea: Northwest 4 to 6, backing southwest 5 to 7, perhaps gale 8 later. Slight or moderate until later in Irish Sea and Lundy, otherwise moderate or rough. Rain or showers. Good, occasionally poor.

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Italy April 1944 discrepancy between comment and data
by Alois Treindl Oct. 5, 2021

Oct. 5, 2021

For Italy in 1944 zone Europe/Rome there is a discrepancy between the comment and the data. comment: # From Paul Eggert (2016-10-27): # Go with INRiM for DST rules, except as corrected by Inglis for 1944 # for the Kingdom of Italy. This is consistent with Renzo Baldini. # Model Rome's occupation by using C-Eur rules from 1943-09-10 # to 1944-06-04; although Rome was an open city during this period, it # was effectively controlled by Germany. Data for Italy is Rule Italy 1944 only - Apr 2 2:00s 1:00 S Data for C-Eur is: Rule C-Eur 1944 1945 - Apr Mon>=1 2:00s 1:00 S where Mon>=1 in 1944 is April 3. So Rome is NOT following C-Eur. I think the rule for Itay is right, only the comment is misleading.

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legal status of information on TZ database
by nadir altinbas Oct. 5, 2021

Oct. 5, 2021

Hye, Is there a RFC document in which "explain rights and responsibilities of icann TZ coordination , about to solve regulation problems become from legal conflicts that third party person or company got and use of changes on TZ database country data by damage of their economic contracts agreement ?04.10.2021regards, Nadir Altinbasnadiraltinbas(a)yahoo.com n.altinbas

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Re: [tz] TZDB use cases
by Hal Murray Oct. 5, 2021

Oct. 5, 2021

Stephen Colebourne said: > So, it turns out that there is, I believe, a critical difference here between > the US view of timezones and the European one. In the US, timezones do not > follow the boundary of the whole country, nor even States. In Europe, by > contrast, timezone boundaries are very much driven by country boundaries. There is another interesting difference. US borders are stable. Czechoslovakia and Yugoslavia have split post 1970. Did all the pieces retain the same TZ info? I think small regions on the France/German border changed sides after WW 1. Are there others? Anything similar post 1970? Have any US/state borders changed when rivers changed their course? If so, do any people live in the regions that changed and/or did anything interesting happen there? -- These are my opinions. I hate spam.

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32-bit section missing transitions in 2021b
by Daniel Fischer Oct. 2, 2021

Oct. 2, 2021

Hi, It looks like 32-bit data generated by 2021b is missing the effects of transitions below INT32_MIN. Before commit 93132d18, zones had a transition at INT32_MIN to the type in use at that time. For example, the Pacific/Port_Moresby zone used to have these two transitions: -2147483648 -> 1 (+10) 2147483647 -> 1 (+10) Starting with commit 93132d18, including in 2021b, only one transition is present: 2147483647 -> 1 (+10) Since clients are supposed to assume type 0 before the earliest transition, this almost always leads to wrong times for some period of time (or all times for extreme cases like Port Moresby). Danny -- Daniel Fischer Rastatt, Germany Oracle Global Services Germany GmbH

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[tz-announce] 2021c release of tz code and data available
by Paul Eggert via tz-announce Oct. 1, 2021

Oct. 1, 2021

The 2021c release of the tz code and data is available. This is a bugfix release that addresses compatibility problems reported since 2021b came out, notably those reported by Stephen Colebourne. Although this release doesn't address the deeper issues about maintenance philosophy and procedures (discussion of which is ongoing), it does merge in changes to address what Stephen reported was his primary problem with 2021b. This release reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Briefly: Revert most 2021b changes to 'backward'. Fix 'zic -b fat' bug in pre-1970 32-bit data. Fix two Link line typos. Distribute SECURITY file. This release is intended as a bugfix release, to fix compatibility problems and typos reported since 2021b was released. Changes to Link directives Revert almost all of 2021b's changes to the 'backward' file, by moving Link directives back to where they were in 2021a. Although 'zic' doesn't care which source file contains a Link directive, some downstream uses ran into trouble with the move. (Problem reported by Stephen Colebourne for Joda-Time.) Fix typo that linked Atlantic/Jan_Mayen to the wrong location (problem reported by Chris Walton). Fix 'backzone' typo that linked America/Virgin to the wrong location (problem reported by Michael Deckers). Changes to code Fix a bug in 'zic -b fat' that caused old timestamps to be mishandled in 32-bit-only readers (problem reported by Daniel Fischer). Changes to documentation Distribute the SECURITY file (problem reported by Andreas Radke). Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2021c.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2021c.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2021c.tar.lz The following convenience links are also available, although they may point to the previous release until the relevant caches are refreshed: https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz Links are also available via plain HTTP, and via FTP from ftp://ftp.iana.org/tz/releases with the same basenames as above. Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. This release corresponds to commit d2c79c4bc68c02b785990a6d4eb161770058078e dated 2021-10-01 14:21:49 -0700 and tagged '2021c' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: 9ed7677744058c58656b47d77d464bad6ef503f2892b53c6abe694e68e73fa123dfc5c11bbcbbb7798f0a6bf1da72b81f8f1c63670839b967e15e58d6d36adad tzcode2021c.tar.gz e8de3a17c38f530b2ec39605699742dd32da5ee92ecf64accaaa5b012a1dac51d1f594adc52660602c3425016520346ab6ad614fa475eb310e17ccdcae93e6ca tzdata2021c.tar.gz a6a86b5b84353c952eec6192222f95f348900dfb414f2dd205fa245515a0f240ba50eab83999f2a5c2cc8e3547406c111aacd96ff9043364d679c86a5e4b0794 tzdb-2021c.tar.lz Here are the GPG digital signatures for the release files: -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFXfJgACgkQ7ZfpDmKq fjReHA/+LiurpLRdXhwkSuhwUKlAQTKmry3F2/zFyobqi+EEEd7naiJIiQbIlScv aZ0cr6Tpq+oP0L8K0EaLMnz9vvb4qd7M3LLGOcrsML8/z0IigMBaA4c8L/Ep3ACa nsLTKESq6bYUJ2SbaFcCFx4KqwA8UEmfhzrPbNxeb3SVgrI1KwUWkpuTCOpewu+g ZYCVO7mFRhLuaD3wCbErtw9g7vQHyHGPGfTDHyc6lPrEbIaY1gwgl6GwBTmJD72a przvxg/0r0X+ZzHH9GZRQaWSDEGXYUdnIwrnS7zwDNk33WO3VwgLWiX2QMGJwiTe wPku4mnGkRhwQLzG+kJxpWe3DJ9/iKFVvxvS3/5RSN1mnELA6xcGOWMTL9cawlwo RkpyN3bLow/9u3wcW2QSrDhCTlGl5kUeK7Qbi20Rji9q2NIO0zrJ732pdr0PgyCN NeuO0YnHUW0bvGO7IMv0JfhQ+VbjB9yAzOg7D2bR2dSVm++38bR8umI757xU/6sT /CTIpmfP67FsXmtg98PbO6rEmoLr7Y/t+JYi/AwzvoHeFS5CAGs9xnTpdk+dBhjh wjLegKDtLZpIUppH9AkJ/T9MAVsfFpsLa2EnteF3LuYZhFTXzLJj3uo3l6Ji0eMZ RRy1jZAxnZ02EoLRIloezzST4pmxIurepluyzvTXVBBuXcoqDk4= =S2t+ -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFXfJgACgkQ7ZfpDmKq fjR/9g/+LOFIZC6n1xKEMn95PsJx2e+zQ4m2/MG1L1KKZdR6kYnvQHL3hh+dXLdr cKRoB6k4AZDaCl7NZDZ8iKgm0nrXnG4/dVEfVOeJn9VHdRyYZ4sg68Nij0yHheRN fcX/ikKwmVaszwj8t+zTmetZOxlJi1mdLyZaQYgBZuM+8Aj+AnB3QUT00yP3j5xP lZgAToYXyLg8KweHnCuD41ZzU8AmsUU2GSfbTryez5lSGnhTsI+tNFtk5w+2fWZZ C0ZAskT//F2k6viFBozeBoodTs955mPKuzyWte6WyhQOTVUySuaeeAU7Dc9SK1k2 nNMTDeQyR78CL39D/X0qmINAif9YKqQ1k0fJFHH1K+pSbhtw0TaqZarQ7JRQnZpC XSIJ9PwpuLLb4k0pBUWYS+r1bZDWrymmgvDO4uNFRFC8LWR4pKyWZ8k34IYQndaV otWbBcThgyz8JJk5mrf113j7qQ3AYiC/y1lVtBpCXpOy1LzYGSTDUqUoHeib8ToD Q3wD1UTPPlo1nh47+cx/Fq1MasdB4MF/OwX7w33nV7TbYgNOHHjb5ROgf7unbaqM 96rtJDRFXFnnPtDOES3xtF4IEEXeoqx1q6AEEcEBBmkCc+DQk5AvW64JwluKn4b1 XSDP7AuXex+wJKffa/7I2KyNLNiX8aLQcnvVsD9cqV4hComR3O8= =LtLe -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFXfJoACgkQ7ZfpDmKq fjTWQA/9Geo9i7m1YlBbU6xJQFyT2AVTTeCgA3wnQOc7VXj5Sy8/7JBU/AJW4Vmi iaTE+XZJU8ghslbdwkyEwoFcZ+4dT8qtjIDSaJ989LV8zpL0MPjgQPdYnh9egaGo qUQBXBcBzzK6giDut7vYcldf5YbK8AAv/ApvVyqL9JjdjbE2P3/juPAHUBUTxHIl bGrnRKbXIeqHB2MGgNZcby4HyblR+BCue3r9kN7Jq0kzETHG8UDeEDeHpL9x9DIq QIYpCiiuMvT7FZR4vNlQg5oBm6Tjz47BEWlvpDQcZHSAgXVrMOTds7uameG72DRW TtEGbozg2LQS3RKHn9mN0GK505d/qiSgrR/AoP420g6xa7d49Orz5qTcE4hUUqQ6 /YA2/3LqqCXeNep/BjwDvsvSTN8TKF4y0iF26Ie2BWRCnI377tT/76NncWaXRT3f k4X2qdIu/6EGle9kleanIZvet3/yavwpOXpgjcMPBwa1RoZDcH2/YSTd0uFhBXLw FTgJ2LKU1d7HVn5VR3t0z1ltjTjv5kjAt+/E/xdANN/vY27ef6yOMp9Mq4z3Pp9Y cUtwwM0aXchlCcomOhoKOShW/j8hFFlIX3pEEAQOhvDS4t7zw0x18+737Fi5diY6 5GUcyKs0sgIkGcAco1qZXd6vvR61ekq7rgMANpi8g9H5igjt5TM= =23yb -----END PGP SIGNATURE----- PS. If your tzdata parser does not yet support negative DST offsets or times past 24:00, or if it insists on a 'pacificnew' file that is no longer present, this release's data entries can be turned into a rearguard-format tarball that should work even with these older parsers. This is intended to be a temporary transition aid for these parsers. To generate a rearguard-format tarball, obtain the full distribution as described above, and run the command 'make rearguard_tarballs' on a development host. Or you can run 'make rearguard.zi' to generate a single file that can be fed directly to a parser that works like 'zic'.

1 0

[tz-announce] 2021b release of tz code and data available
by Paul Eggert via tz-announce Oct. 1, 2021

Oct. 1, 2021

The 2021b release of the tz code and data is available. Partly because it's been so long since 2021a, this release has many changes, noted below. In one area, noted "Merge more location-based Zones" below, the mailing list has had significant trouble coming to a long-term consensus. Because we should publish something before the Samoa change takes effect, this release contains just one step towards making tzdb fairer and more equitable in future releases. This release reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Briefly: Jordan now starts DST on February's last Thursday. Samoa no longer observes DST. Merge more location-based Zones whose timestamps agree since 1970. Move some backward-compatibility links to 'backward'. Rename Pacific/Enderbury to Pacific/Kanton. Correct many pre-1993 transitions in Malawi, Portugal, etc. zic now creates each output file or link atomically. zic -L no longer omits the POSIX TZ string in its output. zic fixes for truncation and leap second table expiration. zic now follows POSIX for TZ strings using all-year DST. Fix some localtime crashes and bugs in obscure cases. zdump -v now outputs more-useful boundary cases. tzfile.5 better matches a draft successor to RFC 8536. A new file SECURITY. This release is prompted by recent announcements by Jordan and Samoa. It incorporates many other changes that had accumulated since 2021a. However, it omits most proposed changes that merged all Zones agreeing since 1970, as concerns were raised about doing too many of these changes at once. It does keeps some of these changes in the interest of making tzdb more equitable one step at a time; see "Merge more location-based Zones" below. Changes to future timestamps Jordan now starts DST on February's last Thursday. (Thanks to Steffen Thorsen.) Samoa no longer observes DST. (Thanks to Geoffrey D. Bennett.) Changes to zone name Rename Pacific/Enderbury to Pacific/Kanton. When we added Enderbury in 1993, we did not know that it is uninhabited and that Kanton (population two dozen) is the only inhabited location in that timezone. The old name is now a backward-compatility link. Changes to past timestamps Correct many pre-1993 transitions, fixing entries originally derived from Shanks, Whitman, and Mundell. The fixes include: - Barbados: standard time was introduced in 1911, not 1932; and DST was observed in 1942-1944 - Cook Islands: In 1899 they switched from east to west of GMT, celebrating Christmas for two days. They (and Niue) switched to standard time in 1952, not 1901. - Guyana: corrected LMT for Georgetown; the introduction of standard time in 1911, not 1915; and corrections to 1975 and 1992 transitions - Kanton: uninhabited before 1937-08-31 - Niue: only observed -11:20 from 1952 through 1964, then went to -11 instead of -11:30 - Portugal: DST was observed in 1950 - Tonga: corrected LMT; the introduction of standard time in 1945, not 1901; and corrections to the transition from +12:20 to +13 in 1961, not 1941 Additional fixes to entries in the 'backzone' file include: - Enderbury: inhabited only 1860/1885 and 1938-03-06/1942-02-09 - The Gambia: 1933 and 1942 transitions - Malawi: several 1911 through 1925 transitions - Sierra Leone: several 1913 through 1941 transitions, and DST was NOT observed in 1957 through 1962 (Thanks to P Chan, Michael Deckers, Alexander Krivenyshev and Alois Treindl.) Merge more location-based Zones whose timestamps agree since 1970, as pre-1970 timestamps are out of scope. This is part of a process that has been ongoing since 2013. This does not affect post-1970 timestamps, and timezone historians who build with 'make PACKRATDATA=backzone' should see no changes to pre-1970 timestamps. When merging, keep the most-populous location's data, and move data for other locations to 'backzone' with a backward link in 'backward'. For example, move America/Creston data to 'backzone' with a link in 'backward' from America/Phoenix because the two timezones' timestamps agree since 1970; this change affects some pre-1968 timestamps in America/Creston because Creston and Phoenix disagreed before 1968. The affected Zones are Africa/Accra, America/Atikokan, America/Blanc-Sablon, America/Creston, America/Curacao, America/Nassau, America/Port_of_Spain, Antarctica/DumontDUrville, and Antarctica/Syowa. Changes to maintenance procedure The new file SECURITY covers how to report security-related bugs. Several backward-compatibility links have been moved to the 'backward' file. These links, which range from Africa/Addis_Ababa to Pacific/Saipan, are only for compatibility with now-obsolete guidelines suggesting an entry for every ISO 3166 code. The intercontinental convenience links Asia/Istanbul and Europe/Nicosia have also been moved to 'backward'. Changes to code zic now creates each output file or link atomically, possibly by creating a temporary file and then renaming it. This avoids races where a TZ setting would temporarily stop working while zic was installing a replacement file or link. zic -L no longer omits the POSIX TZ string in its output. Starting with 2020a, zic -L truncated its output according to the "Expires" directive or "#expires" comment in the leapseconds file. The resulting TZif files omitted daylight saving transitions after the leap second table expired, which led to far less-accurate predictions of times after the expiry. Although future timestamps cannot be converted accurately in the presence of leap seconds, it is more accurate to convert near-future timestamps with a few seconds error than with an hour error, so zic -L no longer truncates output in this way. Instead, when zic -L is given the "Expires" directive, it now outputs the expiration by appending a no-change entry to the leap second table. Although this should work well with most TZif readers, it does not conform to Internet RFC 8536 and some pickier clients (including tzdb 2017c through 2021a) reject it, so "Expires" directives are currently disabled by default. To enable them, set the EXPIRES_LINE Makefile variable. If a TZif file uses this new feature it is marked with a new TZif version number 4, a format intended to be documented in a successor to RFC 8536. zic -L LEAPFILE -r @LO no longer generates an invalid TZif file that omits leap second information for the range LO..B when LO falls between two leap seconds A and B. Instead, it generates a TZif version 4 file that represents the previously-missing information. 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 TZif version 4. The TZif reader now lets leap seconds occur less than 28 days apart. This supports possible future TZif extensions. 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. Fix another bug that caused 'localtime' etc. to crash when TZ was set to a POSIX-conforming but unusual TZ string like "EST5EDT4,0/0,J365/0", where almost all the year is DST. Fix yet another bug that caused 'localtime' etc. to mishandle slim TZif files containing leap seconds after the last explicit transition in the table, or when handling far-future timestamps in slim TZif files lacking leap seconds. Fix localtime misbehavior involving positive leap seconds. This change affects only behavior for "right" system time, which contains leap seconds, and only if the UT offset is not a multiple of 60 seconds when a positive leap second occurs. (No such timezone exists in tzdb, luckily.) Without the fix, the timestamp was ambiguous during a positive leap second. With the fix, any seconds occurring after a positive leap second and within the same localtime minute are counted through 60, not through 59; their UT offset (tm_gmtoff) is the same as before. Here is how the fix affects timestamps in a timezone with UT offset +01:23:45 (5025 seconds) and with a positive leap second at 1972-06-30 23:59:60 UTC (78796800): time_t without the fix with the fix 78796800 1972-07-01 01:23:45 1972-07-01 01:23:45 (leap second) 78796801 1972-07-01 01:23:45 1972-07-01 01:23:46 ... 78796815 1972-07-01 01:23:59 1972-07-01 01:23:60 78796816 1972-07-01 01:24:00 1972-07-01 01:24:00 Fix an unlikely bug that caused 'localtime' etc. to misbehave if civil time changes a few seconds before time_t wraps around, when leap seconds are enabled. Fix bug in zic -r; in some cases, the dummy time type after the last time transition disagreed with the TZ string, contrary to Internet RFC 8563 section 3.3. Fix a bug with 'zic -r @X' when X is a negative leap second that has a nonnegative correction. Without the fix, the output file was truncated so that X appeared to be a positive leap second. Fix a similar, even-less-likely bug when truncating at a positive leap second that has a nonpositive correction. zic -r now reports an error if given rolling leap seconds, as this usage has never generally worked and is evidently unused. zic now generates a POSIX-conforming TZ string for TZif files where all-year DST is predicted for the indefinite future. For example, for all-year Eastern Daylight Time, zic now generates "XXX3EDT4,0/0,J365/23" where it previously generated "EST5EDT,0/0,J365/25" or "". (Thanks to Michael Deckers for noting the possibility of POSIX conformance.) zic.c no longer requires sys/wait.h (thanks to spazmodius for noting it wasn't needed). When reading slim TZif files, zdump no longer mishandles leap seconds on the rare platforms where time_t counts leap seconds, fixing a bug introduced in 2014g. zdump -v now outputs timestamps at boundaries of what localtime and gmtime can represent, instead of the less-useful timestamps one day after the minimum and one day before the maximum. (Thanks to Arthur David Olson for prototype code, and to Manuela Friedrich for debugging help.) zdump's -c and -t options are now consistently inclusive for the lower time bound and exclusive for the upper. Formerly they were inconsistent. (Confusion noted by Martin Burnicki.) Changes to build procedure You can now compile with -DHAVE_MALLOC_ERRNO=0 to port to non-POSIX hosts where malloc doesn't set errno. (Problem reported by Jan Engelhardt.) Changes to documentation tzfile.5 better matches a draft successor to RFC 8536 <https://datatracker.ietf.org/doc/draft-murchison-rfc8536bis/01/>. Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2021b.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2021b.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2021b.tar.lz The following convenience links are also available, although they may point to the previous release until the relevant caches are refreshed: https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz Links are also available via plain HTTP, and via FTP from ftp://ftp.iana.org/tz/releases with the same basenames as above. Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. This release corresponds to commit 9ffa3f6e5019dfa7cfb5c0e4e8a84fa95adec704 dated 2021-09-24 16:23:00 -0700 and tagged '2021b' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: 00fca7508cfbc42123065fe8087397c9dd2acbdda96f3bb0936187825348cf13538f1893f2d02bd8bfa3465427ca7a9a65451baffe39889bc58ba0a77a047806 tzcode2021b.tar.gz ca61d64af5ae791f337533c09d2b4f7caa645ecab7b9d13e9bcafc47c7c68535abe7c103c56bbd41d6bd913a8607f9c5187c8ce8a91b4891a750a643f89c8b51 tzdata2021b.tar.gz 326fb99666c8d5bb798a9c24d2869307620dce918d47fbedd7f765c91eb35ea44bf776f43cb00cde1944884150232ac6dcdc0194a0364e2d28f6470691cf9177 tzdb-2021b.tar.lz Here are the GPG digital signatures for the release files: -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFOX/wACgkQ7ZfpDmKq fjRKwA//RVH1mmf13Uz99KBQZMc/meVaYT1YSpMqilocZo1w+i+Omai7Aw/r9u1e lnwLQukqjpCH4TJWdq8VuloL5ojN1ImoZuIRYECWRHOShxMaS9DLkPRr4qA9Fxic hladneiIglVrnzQbG4pH0Vnu9Qakb6I+1um8lCNiJHng84y5KAOIcZu1m9O+A1F1 bdik8Ddxc4qBluUvcq9n9aqWSgDBvIyCYik6bOo3lOd5zP1rcjSr8VJ+15cAkH4X hU/igj9qloyqAmoOyJOzIIwv63T3Xg63rH/V2hJWyux54ayP4Kt8nZqLYA9V8gFI V/HL5qNafSYEqguO2H3hTwURc3Utini8Oa2Ou89Ih0hkO+nySacc0ZnhaunmX7Ip D5Oj6A8kssG0Uj5fZqpqUp1FeRbziAinSdwTOpRxdkdeHI6tfS0XVnRvRiFATfTu oh9107e3okwKAb2UPJtr8Oev0uU8rz8+EorN9/PqJv0n2c3I69NUv6TudFVHM8uB lwG3hUNtWWYpK/rzwX8AQkwTrOHMN3VJ94T8xaTm13/jtk6R/+GgSjXKC2C9XZG6 5uvi6et06WnRVRO+V5TwnQdfY85pe5nqRDLeo0clxdkAvx6fslLpz9YNacLV/Gn8 0UIGt9CBKjE+PU1F5w+O/5btA/1aTojuSpKscdzgQIzXTfDlTZo= =+McC -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFOX/0ACgkQ7ZfpDmKq fjRYmg/9H3rMpV7uQdd+G2K0wybdzTH6vJiNQClWE1+wqCPh/L3e8kCbPIjSo7MF SFV/Pu4EDb9kjeA2ruEMYlLnpg5nTP7dYfFRsRDcQJ5Yw70luNImm1ipUkKr9o5Q oQqYFKzxvB0G1rE+/gMaxmCHtGaJnv0DEChhmAS5U4j48z71Fn3+UJIU9XPEaODD U1Fw62xDsxIlFKjZ9UvilhlVRMnnP5nK9hjrsFKn7OGbxYvkdaRoK5f3M+G5nGXh L9nZcE0cd/7zhD3+wlttcH+xw3b+5P+7sxMhucoWQXEl3KyIklh97fi7jzHBHz+s DRYLZv/yPoEp94QyCfaYdvWL/i4OX4/9YnXK3ruXDcEV2y8Zl7Wc70Ihxk3I2XAb S4YeMcb30uls93QUdSmuhpEEUWrS5e45OnPy9RnT/VnpCalxsukudSNRzuvivKZn TsPpf90VUtI9ncLZ4l7OoNVXSj5pJ6DS+V1nCesEQyfyFnFvgK/rogCZ0yt+Cosp zaXwBtGyOWwWsGgXHGdJoiQqt/FF8o387EL95vpFr9BRSdSQoKd6K9RrRIH9fuy/ nnpaksD86fx+WbdLMtbHzsZgCqL1RTGO+kc35Qlr3vqH02UAZiwC9l3DHS9SA01c MGDy9zaiLsL/8/lUV3AP31dEP1+DY+BXvdFhIJkmIceBUf7zl0E= =PO3W -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEfjeSqdis99YzvBWI7ZfpDmKqfjQFAmFOX/4ACgkQ7ZfpDmKq fjSaPg//ZlKREhlxjnstpEl6W3x4sStpUrF/Kebp62txYoCjbK22EDnw4BbE0wFh BcIBGbfxioC2+1gAjG57LK0RzTqFPPuDA69qYIZFk+xLrREISDqrGHViLGkFEgm5 jEDamuGW59UoBdnu4Klp1JAd7hvYQYEbbVaIVsrUlAL99OTyujeA6QoZdIjM43eh jx4g1P/XuHBqJEH7d9kOM5tBCRvgFhhcu/s4vOvrfFibRHRimYBuPlep5nJ88bb/ UyCQ1oYIQucWtl+DOszICl/GTmuM33FMTeAX6OrlGxwON6KPI2qNzAaQVpK1apB/ qF9dTnOVP8pygW6HkiFwNOKx4mplB2V8f1eqLT9mfdOQsEWPRuDyUvejBIr/Hmww jHF1w9TX8FxND2KQmcfZNTlKqYcw1O8Vz4m+0UnDzNuLiZAsnTBTrfnKMnVrTOFt 1K6KKK+v5y4WYu+pE36cIBM2YxITEpD+YrRr7G1ilzVgRH5FRGCJsxJu0O+BO35z rv9qVnJz0xISMJs+qSdJT8v4W4Uc6+crnHjAc7T7eAin3i3y/GY/MA44isCACmhx +Rq165laaHXnqTOgQfHhGjigJoH3JCnDYUwg6q+fMMBU2eALkOs+IbgdfVB3hoyo UOlYH/A25nuI0PrRgUKsN6N2lrfPjq3bM4twDw33BOyGJ/LN88w= =aNBd -----END PGP SIGNATURE----- PS. If your tzdata parser does not yet support negative DST offsets or times past 24:00, or if it insists on a 'pacificnew' file that is no longer present, this release's data entries can be turned into a rearguard-format tarball that should work even with these older parsers. This is intended to be a temporary transition aid for these parsers. To generate a rearguard-format tarball, obtain the full distribution as described above, and run the command 'make rearguard_tarballs' on a development host. Or you can run 'make rearguard.zi' to generate a single file that can be fed directly to a parser that works like 'zic'.

17 26

Discussion on LWN on the equity controversy
by Sanjeev Gupta Oct. 1, 2021

Oct. 1, 2021

Folks, On Linux Weekly News (which actually is about more than Linux), there is a summary and discussion on the issues raised here. LWN has a very high signal/noise ratio, I find. I have been a paid subscriber for a couple of decades. Here is a link (LWN allows subscribers to generate a link to an article for viewing by non-subscribers, all content s free after a week): https://lwn.net/SubscriberLink/870478/9dcc3764b87edfaf/ Thanks, -- Sanjeev Gupta +65 98551208 http://www.linkedin.com/in/ghane

2 1

Dropping coordinates from zone1970.tab?
by Aurelien Jarno Oct. 1, 2021

Oct. 1, 2021

Hi, With the recent changes, geographically distant locations share the same timezone and the same coordinates in the zone1970.tab file. For instance Antarctica/Syowa is a link to Asia/Riyadh and appear with the same coordinates in the zone1970.tab file, while they are more than 10000 km apart. The zone1970.tab says: "This table is intended as an aid for users, to help them select timezones appropriate for their practical needs". I have the impression that the coordinates in that table do not anymore aid users to select appropriate timezones, so I wonder if they should just get dropped. Regards, Aurelien -- Aurelien Jarno GPG: 4096R/1DDD8C9B aurelien(a)aurel32.net http://www.aurel32.net

4 16

[PATCH] Formatting of NEWS file is inconsistent in 2021b
by Paul Ganssle Sept. 30, 2021

Sept. 30, 2021

All previous entries in NEWS have a format of headings following nested levels of indentation — the release is unindented, then subheadings with a 2-space indentation, then the contents of each subhead are blocks indented with 2 spaces. In the 2021b release, there is some commentary about the release that isn't indented to the level of the "Briefly" sub-block, but also doesn't have its own heading. I think it would be preferable to put this note under a heading rather than as free-floating content at the level of other subheads. I've attached a patch to move the note into the "Briefly" subheading, though it could also be a separate heading like "Note about the 2021b release" or something. I don't really expect this format to be guaranteed or anything, but for selfish reasons I liked the consistency of the previous format since it makes it much easier for me to parse the NEWS file for repackaging in the Python tzdata format. Obviously I do not consider this any sort of contract or required interface, but since it seems unlikely that accepting this patch would increase your maintenance burden and it will decrease my maintenance burden by a decent amount in the future, I'm hoping you wont' mind accepting this patch (or a similar one). Thanks! Paul

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(no subject)
by Cool Gab19 Sept. 30, 2021

Sept. 30, 2021

I knew that we do already have a time zone for Philippines, Asia/Manila called "Philippine Standard Time" with an offset of UTC+8:00 but the other one I was requesting is for the body of water surrounded inside the mainland such as the Ocean or Sea. I'm proposing to add UTC/GMT+8:15 to your database We do have an 8:30 and 8:45 zone. Why not 8:15? Plus,and if there's an specific location it's Asia/Philippines with different abbreviation "Philippine Pacific Time" with offset of UTC+8;15and will be used inside Philippine sea (not in mainland)

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something wrong with 2021b zdump
by 大山俊成 Sept. 30, 2021

Sept. 30, 2021

I compared 2021b with 2021a. The result is following. I don't understand the meaning for line 3-5,20-22 of 2021b result. Is it correct ? *** tzdb-2021b $ ./zdump -v Pacific/Honolulu Pacific/Honolulu -9223372036854775808 = NULL Pacific/Honolulu -67768040609740801 = NULL Pacific/Honolulu Thu Jan 1 00:00:00 -2147481748 UT = NULL Pacific/Honolulu Thu Jan 1 10:31:25 -2147481748 UT = NULL Pacific/Honolulu Thu Jan 1 10:31:26 -2147481748 UT = Thu Jan 1 00:00:00 -2147481748 LMT isdst=0 gmtoff=-37886 Pacific/Honolulu Mon Jan 13 22:31:25 1896 UT = Mon Jan 13 11:59:59 1896 LMT isdst=0 gmtoff=-37886 Pacific/Honolulu Mon Jan 13 22:31:26 1896 UT = Mon Jan 13 12:01:26 1896 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Apr 30 12:29:59 1933 UT = Sun Apr 30 01:59:59 1933 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Apr 30 12:30:00 1933 UT = Sun Apr 30 03:00:00 1933 HDT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun May 21 21:29:59 1933 UT = Sun May 21 11:59:59 1933 HDT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun May 21 21:30:00 1933 UT = Sun May 21 11:00:00 1933 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Mon Feb 9 12:29:59 1942 UT = Mon Feb 9 01:59:59 1942 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Mon Feb 9 12:30:00 1942 UT = Mon Feb 9 03:00:00 1942 HWT isdst=1 gmtoff=-34200 Pacific/Honolulu Tue Aug 14 22:59:59 1945 UT = Tue Aug 14 13:29:59 1945 HWT isdst=1 gmtoff=-34200 Pacific/Honolulu Tue Aug 14 23:00:00 1945 UT = Tue Aug 14 13:30:00 1945 HPT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun Sep 30 11:29:59 1945 UT = Sun Sep 30 01:59:59 1945 HPT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun Sep 30 11:30:00 1945 UT = Sun Sep 30 01:00:00 1945 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Jun 8 12:29:59 1947 UT = Sun Jun 8 01:59:59 1947 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Jun 8 12:30:00 1947 UT = Sun Jun 8 02:30:00 1947 HST isdst=0 gmtoff=-36000 Pacific/Honolulu Wed Dec 31 23:59:59 2147485547 UT = Wed Dec 31 13:59:59 2147485547 HST isdst=0 gmtoff=-36000 Pacific/Honolulu 67768036191676800 = Wed Dec 31 14:00:00 2147485547 HST isdst=0 gmtoff=-36000 Pacific/Honolulu 67768036191712799 = Wed Dec 31 23:59:59 2147485547 HST isdst=0 gmtoff=-36000 Pacific/Honolulu 67768036191712800 = NULL Pacific/Honolulu 9223372036854775807 = NULL *** tzdb-2021a $ ./zdump -v Pacific/Honolulu Pacific/Honolulu -9223372036854775808 = NULL Pacific/Honolulu -9223372036854689408 = NULL Pacific/Honolulu Mon Jan 13 22:31:25 1896 UT = Mon Jan 13 11:59:59 1896 LMT isdst=0 gmtoff=-37886 Pacific/Honolulu Mon Jan 13 22:31:26 1896 UT = Mon Jan 13 12:01:26 1896 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Apr 30 12:29:59 1933 UT = Sun Apr 30 01:59:59 1933 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Apr 30 12:30:00 1933 UT = Sun Apr 30 03:00:00 1933 HDT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun May 21 21:29:59 1933 UT = Sun May 21 11:59:59 1933 HDT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun May 21 21:30:00 1933 UT = Sun May 21 11:00:00 1933 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Mon Feb 9 12:29:59 1942 UT = Mon Feb 9 01:59:59 1942 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Mon Feb 9 12:30:00 1942 UT = Mon Feb 9 03:00:00 1942 HWT isdst=1 gmtoff=-34200 Pacific/Honolulu Tue Aug 14 22:59:59 1945 UT = Tue Aug 14 13:29:59 1945 HWT isdst=1 gmtoff=-34200 Pacific/Honolulu Tue Aug 14 23:00:00 1945 UT = Tue Aug 14 13:30:00 1945 HPT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun Sep 30 11:29:59 1945 UT = Sun Sep 30 01:59:59 1945 HPT isdst=1 gmtoff=-34200 Pacific/Honolulu Sun Sep 30 11:30:00 1945 UT = Sun Sep 30 01:00:00 1945 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Jun 8 12:29:59 1947 UT = Sun Jun 8 01:59:59 1947 HST isdst=0 gmtoff=-37800 Pacific/Honolulu Sun Jun 8 12:30:00 1947 UT = Sun Jun 8 02:30:00 1947 HST isdst=0 gmtoff=-36000 Pacific/Honolulu 9223372036854689407 = NULL Pacific/Honolulu 9223372036854775807 = NULL ---- Toshinari Ohyama

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Merged 1970+ time zones should always return -1 pre-1970
by Brian Inglis Sept. 29, 2021

Sept. 29, 2021

I think for all zones with data merged prior to 1970, the data and API should always return *-1* for all times prior to 1970-01-01 00:00:00Z, as anything else is inaccurate or a kludge. Arbitrary disposition of any valid historical data is itself really political, for ease of administration, not really technical. I firmly believe that no decision on the list has ever been made on a basis of in-/equity or un-/fairness, as those would be political decisions, and we have bent over backwards for years to avoid any such appearance never mind actuality, devoting probably the majority of the volume of posts and the majority of the volume of words to such discussions. I have always taken the position that any churn not necessitated by changes on the ground (or government offices) is detrimental to the project and the database, and places a massive burden on downstreams who make good use of that data, including the CLDR and ICU projects, astronomy and astrology applications, all facets of the transportation industry, the databases they maintain, and the storage of what was the truth at a previous point in time, and future application uses of that previously stored data. Any such churn should be mediated by the request the list makes of time zone decision makers: to provide adequate notice of such changes, at least six months, preferably longer. I can only believe that the adminstrators of this database are under some form of political pressure (perhaps /only/ "vitriol in private email", which appears to be nearing the norm in certain arenas) to dispose of some data to achieve some misguided form of "equity" and "fairness", in response to some misguided perception of "inequity" and "unfairness" that is not apparent to members of this mailing list, and from the reactions, nor does it appear to have been adequately or clearly expressed in a form that members of this list can readily comprehend, nor is it clearly exactly when these political terms entered the discussion, nor what business they have being in it. As in any project where decisions are questionable, it is necessary to back off making any! The proposers of drastic changes need to enunciate clearly: * exactly what technical problem they perceive, and why it appears to be a problem; * some alternative options for technical solutions and/or approaches to address the technical problem; * how each alternative option for technical solutions and/or approaches to address the problem will satisfy the majority of needs of the majority of the stakeholders, and impacts on those unsatisfied; * why they think the option they propose to adopt is the best and most comprehensive solution to address the problem, and satisfies the most needs of the most stakeholders. This is standard practice in most commercial projects. It is often used when stakeholders can not quickly make a decision, decide on policy, or easily change policy. It allows development to proceed in parallel on all the offered options. When stakeholders finally decide or act, perhaps months along the timeframe nearing release, the selected option can be preferentially enabled, possibly with only minor tweaks or just data changes, and quickly regression tested to ensure the effect is precisely as desired. Of course, the best decision to satisfy the most needs of the most stakeholders is often the decision to just say "NO !" ;^> -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada This email may be disturbing to some readers as it contains too much technical detail. Reader discretion is advised. [Data in binary units and prefixes, physical quantities in SI.]

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Using the tzdb: What's actually changed
by Watson Ladd Sept. 29, 2021

Sept. 29, 2021

Dear all, I see lots and lots of people who seem to be running applications that care about pre 1970 timestamps and don't use backzones, or seem to ignore links. Well, if you ignore links you deserve what you get: it's been documented that zones may become links. The size of tzdb has already caused problems for some embedded devices. Post-1970 correctness only strikes me as very reasonable. Applications that need more should use backzones, and this has been true for years. If you care about the truth of what time something happened, and it was recorded in local time, and the zone that it was in might need to get split in the future, and that split could change when the time was or other times you care about then the database isn't your problem, reality is. I see a lot of complaints, and very few details about the applications affected. Which makes me skeptical they actually exist. Remember, you're only affected if you deal with pre-1970 timestamps. Sincerely, Watson -- Astra mortemque praestare gradatim

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[PATCH] Port better to >64-bit platforms
by Paul Eggert Sept. 29, 2021

Sept. 29, 2021

* zic.c (limitrange, writezone): Use max_time instead of ZIC_MAX when dealing with timestamps that would go into the TZif file. The distinction matters only on very unusual platforms where int_fast64_t is wider than 64 bits. --- zic.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/zic.c b/zic.c index c6feb8b..224cc22 100644 --- a/zic.c +++ b/zic.c @@ -1990,7 +1990,7 @@ limitrange(struct timerange r, bool locut, zic_t lo, zic_t hi, /* Omit ordinary and leap second transitions greater than HI + 1. */ - if (hi < ZIC_MAX) { + if (hi < max_time) { while (0 < r.count && hi + 1 < ats[r.base + r.count - 1]) r.count--; while (0 < r.leapcount && hi + 1 < trans[r.leapbase + r.leapcount - 1]) @@ -2205,7 +2205,7 @@ writezone(const char *const name, const char *const string, char version, error(_("too many transition times")); thistimelim = thistimei + thistimecnt; - if (thistimecnt && hi_time < ZIC_MAX + if (thistimecnt && hi_time < max_time && ats[thistimelim - 1] == hi_time + 1) hicut = false; memset(omittype, true, typecnt); -- 2.30.2

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Request
by Cool Gab19 Sept. 29, 2021

Sept. 29, 2021

I'm proposing to add UTC/GMT+8:15? We do have an 8:30 and 8:45 zone. Why not 8:15? Plus,the GMT+8:15 if ever will be named as Anywhere on Southeast Asia Time (ASAT) (Asia/Southeast) a very usable time zone in southeast asian countries specially in zone 7 and 8.

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Re: [tz] [EXTERNAL] [tz-announce] 2021b release of tz code and data available
by Paul Eggert Sept. 28, 2021

Sept. 28, 2021

On 9/28/21 5:57 AM, crdrequest(a)ups.com wrote: > I was informed that the start Jordan now starts DST on February's last FRIDAY.....NOT THURSDAY. My guess is that you're OK because your informant referred to 00:00 on February's last Friday, which in 2022 is equivalent to what we have in tzdb 2021b (namely, 24:00 on February's last Thursday). The distinction between the two rules matters only in one year out of seven, the first such year being 2024 when February ends on a Thursday. Our source for the 24:00-on-last-Thursday rule is here (in Arabic): https://petra.gov.jo/Include/InnerPage.jsp?ID=189969&lang=ar&name=news

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Why 2021b needed to be issued
by Paul Eggert Sept. 28, 2021

Sept. 28, 2021

Since 2013 I've been patching tzdb by replacing Zones with Links when Links suffice according to the guidelines. These patches have not affected timestamps after 1970. I've been doing this gradually. The changes have worked without significant incident, partly because end users generally don't care about pre-1970 timestamps, and partly because the few users who do care (astrologers, mostly) know or should know that the pre-1970 Zone data entries are often wrong and even when right are typically grossly inadequate for realistic use outside the named location - this is partly why any focus on pre-1970 is out of scope for tzdb. Preparing all these patches has been a big enough job that I've been doing it gradually since I have limited time. This process was discussed on the list before it began, and although there was some objection, a consensus to move towards these goals was reached at the time. Most of this job was done before 2021a came out. The main difference in this round of patches, is that I had aimed to complete the job, in response to a user query raising equity concerns in 2021a. It is clear that the 2021a setup was not sustainable in the long term, if equity is a goal. Completing the job generated larger patches than usual, and the patches' size triggered concern that they held too many changes all at once. Also, the patches' effects on pre-1970 timestamps in (for example) Norway and Sweden have triggered concerns, much more so than similar changes made (for example) to Angola and Congo in tzdb 2014g. My own view is that we've done this before, many times, it hasn't been a problem in practice, and it's way past time to address the equity concerns as they have a good chance to really bite this project and its repackagers in the future. It's a bad look for us that so much concern about Norway and Sweden has appeared on this mailing list, even though hardly anybody seems to have cared about Angola and Congo. It'll be an even worse look if we ignore this issue weeks, months or even years after it's been made clear to us. I wrote, tested and published several concrete suggestions addressing the fairness problem. In the months since May when the fairness problem was discovered and objections to my proposed fixes were raised, no other concrete fix addressing both of these concerns has been implemented or tested, and all other suggestions made so far would have required significant work, if they would have worked at all, or would have caused more data churn than what I proposed. I realize that there are valid concerns about installing too many of these patches at once, so 2021b affects only nine Zones instead of the thirty-odd Zones in my May proposal. The idea is to do further patch sets in not-too-distant-future releases, so that the job can finally be finished. I also recognize that there are other forms of equity and fairness that should be considered, perhaps along with alternative technical solutions to the problems these patches address. With all this in mind, issuing 2021b now is a significant step toward equity in tzdb. It will let us say that we are moving toward a fair process, and will give us the opportunity and motivation to improve on that process and to address and balance the various other concerns that have recently appeared on the mailing list.

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Preparing to fork tzdb
by Stephen Colebourne Sept. 27, 2021

Sept. 27, 2021

Hi all, As most of you probably know, there is a dispute about the tzdb maintainer's recent changes to merge large numbers of time-zones [1][2]. These have the effect of wiping out historic time-zone information on many locations where the data has been in tzdb for many years. It appears that there is soon to be a new release of tzdb containing these changes. In my opinion, the correct behaviour of the tzdb maintainer would be to revert the controversial changes before doing a release. In the event that the tzdb maintainer does not revert, consideration must be given to forking the project. The purpose of the fork would initially be to maintain the tzdb data set as it was prior to the dispute. This would then be released in parallel to the original tzdb to ensure that downstream projects do not each do their own thing (ie. to minimize incompatibilities downstream). Is there support for a fork? Is anyone willing to help out? Is any other group willing to sponsor tzdb (eg. CLDR or Red Hat)? Please reply to this thread with an indication of support and/or help. thanks Stephen Colebourne [1] https://mm.icann.org/pipermail/tz/2021-June/thread.html [2] https://mm.icann.org/pipermail/tz/2021-September/030372.html

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