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Gwillim Law
by Paul Eggert Oct. 21, 2016

Oct. 21, 2016

I recently found out about Gwillim Law's passing by reading his family's web page <http://statoids.com/mgtletter.html>. Gwillim was a long time contributor to the tz project. He is credited in dozens of places, ranging from a 1993 decoding of entries for Tocantins in the International Air Transport Association's Standard Schedules Information Manual, to a 2015 translation of an article about a new time zone for Quintana Roo. Although I never met Gwillim in person, his expert, careful, and warm presence on the tz mailing list will be greatly missed. My condolences to his friends and family.

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[tz-announce] 2016h release of tz code and data available
by Paul Eggert Oct. 20, 2016

Oct. 20, 2016

The 2016h release of the tz code and data is available. Its primary motivation is to update to the new rules for Palestine, where 2016g becomes incorrect starting about four hours from now (sorry, we didn't get much notice). More generally, the 2016h release reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Changes to future time stamps Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that future fall transitions will be on the last Saturday of October at 01:00, which is consistent with predicted spring transitions on the last Saturday of March. (Thanks to Tim Parenti.) Changes to past time stamps In Turkey, transitions in 1986-1990 were at 01:00 standard time not at 02:00, and the spring 1994 transition was on March 20, not March 27. (Thanks to Kıvanç Yazan.) Changes to past and future time zone abbreviations Asia/Colombo now uses numeric time zone abbreviations like "+0530" instead of alphabetic ones like "IST" and "LKT". Various English-language sources use "IST", "LKT" and "SLST", with no working consensus. (Usage of "SLST" mentioned by Sadika Sumanapala.) Changes to code zic no longer mishandles relativizing file names when creating symbolic links like /etc/localtime, when these symbolic links are outside the usual directory hierarchy. This fixes a bug introduced in 2016g. (Problem reported by Andreas Stieger.) Changes to build procedure New rules 'traditional_tarballs' and 'traditional_signatures' for building just the traditional-format distribution. (Requested by Deborah Goldsmith.) The file 'version' is now put into the tzdata tarball too. (Requested by Howard Hinnant.) Changes to documentation and commentary The 'Theory' file now has a section on interface stability. (Requested by Paul Koning.) It also mentions features like tm_zone and localtime_rz that have long been supported by the reference code. tz-link.htm has improved coverage of time zone boundaries suitable for geolocation. (Thanks to heads-ups from Evan Siroky and Matt Johnson.) The US commentary now mentions Allen and the "day of two noons". The Fiji commentary mentions the government's 2016-10-03 press release. (Thanks to Raymond Kumar.) Here are links to the release files: ftp://ftp.iana.org/tz/releases/tzcode2016h.tar.gz ftp://ftp.iana.org/tz/releases/tzdata2016h.tar.gz ftp://ftp.iana.org/tz/releases/tzdb-2016h.tar.lz The files are also available via HTTP as follows: http://www.iana.org/time-zones/repository/releases/tzcode2016h.tar.gz http://www.iana.org/time-zones/repository/releases/tzdata2016h.tar.gz http://www.iana.org/time-zones/repository/releases/tzdb-2016h.tar.lz As usual, links to the latest release files are here: http://www.iana.org/time-zones/repository/tzcode-latest.tar.gz http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz http://www.iana.org/time-zones/repository/tzdb-latest.tar.lz ftp://ftp.iana.org/tz/tzcode-latest.tar.gz ftp://ftp.iana.org/tz/tzdata-latest.tar.gz ftp://ftp.iana.org/tz/tzdb-latest.tar.lz 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 6349f541e2183a00b9909af00b480c58955474cf dated 2016-10-19 23:17:57 -0700 and tagged '2016h' in the experimental github repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: 109204356f8105b50d1e563c9a33f140a4af7ea38bfb720756f1fce863a346387d3897dfbd506da94fadcd10f35dc50d6475c6dfc047764dd308e21ee6291c18 tzcode2016h.tar.gz 8d4eeaebe39392ca9163d03601d1178597b3f0092419d1f54ebd34944110a0b10cb22d4ab8bacfb48bce3f6f7175177105e204f1b4edeadc38ad4ac2d6ded835 tzdata2016h.tar.gz fab2dd36b2c85a48d15cdbdbceb70ae6b30077cb83e582706b56d1e4dd24f945dede25ebd115b4bafa3e514a1d628c3d7f9a2da63f19f10942cd38dc8a16c155 tzdb-2016h.tar.lz Here are the GPG checksums for the release files: -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJYCGLlAAoJEO2X6Q5iqn40hxQP/iamwTHAfVWNxb9yu+Xz8DeV 3kYZJF1ln6kkgmTqASn/L1m5VnaO8e4gVjwpYmkUavYUKZBCHkw9GxclNS5Qt3hI tDm2yE7vAvH23/zgo/NWeFtIzpp476W+VcIlCaSCo0iJ008rPxvIiBmFfgAg9Jji xUPYBBNHH1fLVIpyD2xCzwdeoDiJITX45CtWeGoT2uwA+4xbtfv1/NVMu8j7SN9w 7mpUTF2sAoMUdmG56TE0B8Y4vP3BwlqmVq8CadA4yj0DDwg+vyHKI7wkk9uP44+g DDmcZc9vK8P934veSsexNDLjdAxWSHkgcZ1IwGIPjl5/nquosPy5CdF6VqZFS+IX 9ruapyouZlXlfgg+I6pofkQw4WInO+tn0mIZxJHKXfv33aIxMU22m5ddvCJ0+hUf JIMgrkf0dGzlc8g2FT0DYVtDRg7Zik0GrszjmPc8jzeLi31oGxWA4Xjpwm8rYX/p 7kwIGwg3R19OwUaSgDjpEzXgXi3+iyNeLgq28YjhXj9p4iDhVUo+Njl8Kl31H1Vt 7gpo3utpRcT41nX/5yVUVcx4mJjvNwzD36/zc7hoTTQIInyrR5jQAZ5danDr/HCp NoK16D7WgbMaZMD0M0UV4RyTBlHKc0qeyL++xT7WLESCLxOpmVQdB/CYLjx0BZUr UAq95YoKcMMv+3KHjsDG =aC8a -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJYCGLlAAoJEO2X6Q5iqn40FNcP/RX7P5yEnZCRQ4FHHSFg9oIN Hsbp+7R9J9ap5egW8qPVu4HXzmbIzVbED/iCYWah+OMHI9ivJhRTVgPMhHcGco/k Qe8cb72EJIFc/N62BJyPoi48XqrDlw7bJGUuP0+bQGDG8Mik6RqTfOw3kUiUZT+y 9d/NfjQv8k/ASVxaag4FTKhcC9GeKHT51GDdFY9cRam4dgADXdqqsDAhPPeBeKrU hcZEtXaFYZzYvdBjmR7jK/2OYsSGatFeZY5aHxUi4dEmQ2WTv5/3nj6uOe1oHTjw X+xxrYcqINxPC3ss/VHT1fn8X1gQSsbAo/Vp9M9njdXCXCoOu/pSvpnyS4TZi/a6 CGSeGOr3Bz2hYQ1zIegr1QQgcgaK8LP/kl9IJ7dm6yBLVo0NZulzsJ9hRyZwDgWV +BhaPt5IZ0ktQNW8vU5HXrF7ic4qGdCKbcZOUr3DJaOcGHN92QpXS2cgvfZN/+8S uOWGdbCJIcaBmdfe3v9m4I/CKXi8ymb5ZXMDrPwkY6mDokqCG6s6Wfo++zlh1PPT E3Ix3HXfgYBrmByRxtJFwvI/l0VbzpfvOd4HcKuzWQltR5WYvPzdPB6HHLQGdsj7 2BFVXkFPKm1c0NMwB7u5xxvQiVRn1fjz+nLcP9BgZqASCVtREDu91GbRsNntFjzM MbBfIJc99AZIjc9hBjeI =dGny -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJYCGLlAAoJEO2X6Q5iqn40aGAP/iN1k3MtoTiYqnUR5NZyR6it c8grrRznviOPpjEk8/bfT0XpPGY1hwq1ctuuwHbylAFMVT7D4tM9csvDErP3bMNg ewDqBltrtLUzYEA66041AM3wLDTqe/lRqEXiNAPKSmulY4UM1FYHs9qpJ5rFXyOD bD6hkB0mppG/stQ3odfqM0EBZMPCjIZyPqZE4UcE4CY56ZN9R4Fa+R4urtyLRjhL OZqApSDeNtxX+cOPg5QlLO0jxhpO5649zjr7hCkHwXSi9Ji6CzKhiMz3RwJ9L4os VsX6Jg0QTZ68JVa3Zf+i/ysRCMvWQHvBxT3lG5aWrrrCpqvZKVgplFe/MSwbsMDH 3+5ws/+7aPS/QkeZo3WYS/0NisVgKUiKq5zH6PmhzfcfD0CMUUqS/fuHmP3cf1Vl rVRubxg0PgpThFLNdOMNa6c8L7lqzuV5Hwelq3yknM+1V02aTBHRFaU3Sh/gmest qRhb1GD+DO84Qm2JXL3kZXL1UGQq7EbH25r8DJAHHObx1TWyGTrLIE0MmS3LMZz5 zNzXMhaEBNufOQQz8LFwLJEiY4+WFem5VZAjE62GMl8iHhxCYJbuu+J3GeOcuP/l IFVLevVfoqa70CQTzKG7iEDhGwWmO3QdcmC261opbW1FPGnjiy+gOilayHse6ITX gt2dd+COJxgg7TlYv/vB =nbsq -----END PGP SIGNATURE----- _______________________________________________ tz-announce mailing list tz-announce(a)iana.org https://mm.icann.org/mailman/listinfo/tz-announce

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Geolocation extension to tzdist
by Ken Murchison Oct. 20, 2016

Oct. 20, 2016

All, (sending to tz(a)iana.org since tzdist(a)ietf.org appears to be dead) I was bored today (actually avoiding "real" work) and was playing around with the ESRI shapefile for timezones <http://efele.net/maps/tz/world/> I hacked up a quick extension to my tzdist implementation using the tz_world shapefile and basic ray tracing to be able to query a time zone by geo coordinates, similar to what Google offers in their Time Zone API. Note that I have yet to spend any time writing code to account for "holes" in time zones like the Navajo Reservation in Arizona. I modeled the extension after the "find" action in RFC 7808 but with lat/long query params rather than a glob pattern. A request and response for the timezone in which my home is located looks something like this: GET /tzdist/zones?latitude=43.070833&longitude=-78.831667 HTTP/1.1 { "synctoken": "890939292-1466089793", "timezones": [ { "tzid": "America/New_York", "etag": "6602582-1466089793", "last-modified": "2016-06-16T15:09:53Z", "publisher": "IANA Time Zone Database", "version": "2016e", "aliases": [ "US/Eastern" ] } ] } The definition of the extension looks like this in the capabilities response: { "name": "geolocate", "uri-template": "/zones{?latitude,longitude}", "parameters": [ { "name": "latitude", "required": true }, { "name": "longitude", "required": true } ] } Currently my code only accepts coordinates in decimal degrees, but I think it should probably support ISO 6709 formats. Is this something that folks would like to see documented as a formal extension to tzdist, either as specified above or with some modification? If so, I'd be willing to write it up as a draft and then move it through IETF in whatever fashion the ADs recommend. -- Kenneth Murchison Principal Systems Software Engineer Carnegie Mellon University

4 5

[PATCH] Change abbreviation of Sri Lanka standard time to SLST
by Sadika Sumanapala Oct. 20, 2016

Oct. 20, 2016

According to http://www.sltime.org (maintained by Measurement Units, Standards & Services Department, Sri Lanka) abbreviation for Sri Lanka standard time is SLST. --- asia | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/asia b/asia index 71ef878..dcc8465 100644 --- a/asia +++ b/asia @@ -2768,6 +2768,10 @@ Zone Asia/Singapore 6:55:25 - LMT 1901 Jan 1 # One possibility is that we wait for a bit for the dust to settle down # and then see what people actually say in practice. +# From Sadika Sumanapala (2016-10-18): +# According to http://www.sltime.org (Official web site of dissemation +# of standard time of Sri Lanka) abbreviation is SLST. + # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Colombo 5:19:24 - LMT 1880 5:19:32 - MMT 1906 # Moratuwa Mean Time @@ -2777,7 +2781,7 @@ Zone Asia/Colombo 5:19:24 - LMT 1880 5:30 - IST 1996 May 25 0:00 6:30 - LKT 1996 Oct 26 0:30 6:00 - LKT 2006 Apr 15 0:30 - 5:30 - IST + 5:30 - SLST # Syria # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S -- 2.10.0

7 18

Palestine Summer Time wrong ending date
by Sharef Mustafa Oct. 19, 2016

Oct. 19, 2016

Hi, Regarding Palestine end of summer time (Asia/Gaza + Asia/Hebron), the current tz database shows that summer time will end on Oct 20th 2016, sharef@plug.ps:/usr/share/zoneinfo$ zdump -v Asia/Gaza | grep 2016 Asia/Gaza Fri Mar 25 22:59:59 2016 UT = Sat Mar 26 00:59:59 2016 EET isdst=0 gmtoff=7200 Asia/Gaza Fri Mar 25 23:00:00 2016 UT = Sat Mar 26 02:00:00 2016 EEST isdst=1 gmtoff=10800 Asia/Gaza Thu Oct 20 20:59:59 2016 UT = Thu Oct 20 23:59:59 2016 EEST isdst=1 gmtoff=10800 Asia/Gaza Thu Oct 20 21:00:00 2016 UT = Thu Oct 20 23:00:00 2016 EET isdst=0 gmtoff=7200 also for westbank Hebron sharef@plug.ps:/usr/share/zoneinfo$ zdump -v Asia/Hebron | grep 2016 Asia/Hebron Fri Mar 25 22:59:59 2016 UT = Sat Mar 26 00:59:59 2016 EET isdst=0 gmtoff=7200 Asia/Hebron Fri Mar 25 23:00:00 2016 UT = Sat Mar 26 02:00:00 2016 EEST isdst=1 gmtoff=10800 Asia/Hebron Thu Oct 20 20:59:59 2016 UT = Thu Oct 20 23:59:59 2016 EEST isdst=1 gmtoff=10800 Asia/Hebron Thu Oct 20 21:00:00 2016 UT = Thu Oct 20 23:00:00 2016 EET isdst=0 gmtoff=7200 However the Palestinian cabinet decision ( Mar 8th 2016) published on http://www.palestinecabinet.gov.ps/WebSite/Upload/Decree/GOV_17/16032016134… states that summer time will end on Oct 29th at 01:00 . There has been no recent updates from the government in this regard, I suggest to correct the end date accordingly. BR Sharef Mustafa

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Suggestion for addition of America/Brasilia entry to time zone database
by Gabriel Gaspar Oct. 19, 2016

Oct. 19, 2016

Hello there, and sorry for the intrusion. I presently write to this list with a suggestion for addition of an entry in the time zone database, America/Brasilia, or at least for a clarification on why there may not be one. Being the standard official time in Brazil, I firmly believe there should be one such entry (unless, of course, matters of greater power disallow it). The official time used in Brazil is called "the Brasilia official time" (UTC -3:00), Brasilia being the capital of Brazil. Note that the official country name is Brasil, with an 's', and the official capital name is Brasília, with an acute on the first 'i'. I am writing the country name with 'z' and leaving the aforementioned acute out for internationalization purposes. Inside Brazilian territory, the remainder time zones are usually referred and adjusted having Brasilia time as a referential base, e.g. "Brasilia time +1", "Brasilia time -1" etc. Even more, event times in Brazil (games, DST start/end, official announcements) are all informed, be it via government official channels or mass media, in Brasilia's official time, further evidencing the importance of Brasilia as a reference for setting times inside country territory. That being said, I have always wondered why it is that Brasilia is not listed as one of the time zones in the data base for South America. It is the official time for Brazil and the name does not clash with any other name in the database (America/Brasilia). Instead, it is relegated to an indirect mention, (Brasilia is located inside Distrito Federal (DF)), in a comment for the time zone America/Sao_Paulo. São Paulo is a major city in Brazil, but by no means the capital itself, nor does it retain any authoritative power in setting or representing the official time, which Brasilia does. Actually, the America/Sao_Paulo time zone entry seems to be doing what an America/Brasilia time zone entry should be doing. Thus, my suggestion would be either for the addition of something such as America/Brasilia to the time zone database, or for the renaming of America/Sao_Paulo to America/Brasilia in order to more accurately represent what that time zone entry stands for. The former suggestion would add more information to the database, but other than occupying more space I fail to see further problems with that addition. The latter suggestion could break some scripts that rely on the time zone name for correct operation, although I currently have no knowledge of one such script nor how crucial its operation could be. Without further ado, I thank you for the time to read this, and appreciate the time for such considerations. Regards, Gabriel G. Gaspar

3 2

Crimea status
by Adam Golovenko Oct. 15, 2016

Oct. 15, 2016

Hello, last time I used data from unicode.org which use time zone information from your time zones database. I found one moment: RU +4457+03406 Europe/Simferopol MSK+00 - Crimea Timezone "Europe/Simferopol" (and Simferopol city itself) should belong to Ukraine (UA), not Russia (RU). Crimea, as temporary occupied area in all international documents states as ukrainian territory. More details can be found here: http://usa.mfa.gov.ua/en/legal_aspects https://en.wikipedia.org/wiki/United_Nations_General_Assembly_Resolution_68… It's not political position or some other sort of things to argue with. In this case one country (Russia) temporarily occupied part of another country (Ukraine), but no countries except Russia itself treat it legal. So UN with most votes (countries) decided to treat Crimea still as a part of Ukraine and this position should be used for all international materials and communications. Please make changes to your data, returning Europe/Simferopol to correct country. Otherwise ukrainian government (if officially notified) will insist on making changes in documents in juridical manner (there were some precedents with Coca-Cola company, french national maps agency and several more). Thanks in advance, will be glad to receive a responce!

2 1

New shapefile of world's timezones based off of Open Street Map data
by Evan Siroky Oct. 11, 2016

Oct. 11, 2016

Hello All, I have just made a first release of a shapefile of the geographic extent of the timezone database based mostly off of Open Street Map data. All of the borders between countries, states and cities come directly from Open Street Map. This shapefile also includes the territorial waters of countries as defined in Open Street Map. Please see my github project for more details. The shapefile can be found in the project releases. https://github.com/evansiroky/timezone-boundary-builder Evan.

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[PROPOSED PATCH] * tz-link.htm: Add section IDs.
by Paul Eggert Oct. 11, 2016

Oct. 11, 2016

--- tz-link.htm | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) diff --git a/tz-link.htm b/tz-link.htm index ed926c7..43188a4 100644 --- a/tz-link.htm +++ b/tz-link.htm @@ -10,7 +10,7 @@ content="Sources for time zone and daylight saving time data"> <meta name="DC.Creator" content="Eggert, Paul"> <meta name="DC.Contributor" content="Olson, Arthur David"> -<meta name="DC.Date" content="2016-09-21"> +<meta name="DC.Date" content="2016-10-11"> <meta name="DC.Description" content="Sources of information about time zones and daylight saving time"> <meta name="DC.Identifier" @@ -27,7 +27,7 @@ histories and planned futures are often recorded only fitfully. Here is a summary of attempts to organize and record relevant data in this area. </p> -<h2>The <code><abbr title="time zone">tz</abbr></code> database</h2> +<h2 id="tzdb">The <code><abbr title="time zone">tz</abbr></code> database</h2> <p> The <a href="https://en.wikipedia.org/wiki/Public_domain">public-domain</a> time zone database contains code and data @@ -152,7 +152,7 @@ The code lets you compile the <code><abbr>tz</abbr></code> source files into machine-readable binary files, one for each location. It also lets you read a <code><abbr>tz</abbr></code> binary file and interpret time stamps for that location.</p> -<h2>Changes to the <code><abbr>tz</abbr></code> database</h2> +<h2 id="changes">Changes to the <code><abbr>tz</abbr></code> database</h2> <p> The <code><abbr>tz</abbr></code> code and data are by no means authoritative. If you find errors, please @@ -194,7 +194,7 @@ For further information about updates, please see <a href="https://tools.ietf.org/html/rfc6557">Procedures for Maintaining the Time Zone Database</a> (Internet <abbr title="Request For Comments">RFC</abbr> 6557).</p> -<h2>Commentary on the <code><abbr>tz</abbr></code> database</h2> +<h2 id="commentary">Commentary on the <code><abbr>tz</abbr></code> database</h2> <ul> <li>The article <a href="https://en.wikipedia.org/wiki/Tz_database">tz database</a> is @@ -212,7 +212,8 @@ href="https://blog.jonudell.net/2009/10/23/a-literary-appreciation-of-the-olsonz literary appreciation of the Olson/Zoneinfo/tz database</a> comments on the database's style.</li> </ul> -<h2>Web sites using recent versions of the <code><abbr>tz</abbr></code> database</h2> +<h2 id="web">Web sites using recent versions of the +<code><abbr>tz</abbr></code> database</h2> <p> These are listed roughly in ascending order of complexity and fanciness. </p> @@ -242,7 +243,7 @@ calculates the current time difference between locations.</li> also contains data about time zone boundaries; it supports queries via place names and shows location maps.</li> </ul> -<h2>Network protocols for <code><abbr>tz</abbr></code> data</h2> +<h2 id="protocols">Network protocols for <code><abbr>tz</abbr></code> data</h2> <ul> <li>The <a href="https://www.ietf.org">Internet Engineering Task Force</a>'s <a href="https://datatracker.ietf.org/wg/tzdist/charter/">Time Zone Data @@ -267,7 +268,7 @@ title="Extensible Markup Language">XML</abbr></a> format, and a variant uses <a href="http://www.json.org"><abbr title="JavaScript Object Notation">JSON</abbr></a> format.</li> </ul> -<h2>Other <code><abbr>tz</abbr></code> compilers</h2> +<h2 id="compilers">Other <code><abbr>tz</abbr></code> compilers</h2> <ul> <li><a href="https://sourceforge.net/projects/vzic/">Vzic</a> is a <a href="https://en.wikipedia.org/wiki/C_%28programming_language%29">C</a> @@ -390,7 +391,7 @@ source into text files, along with a runtime that can read those files. Tcl is freely available under a <abbr>BSD</abbr>-style license.</li> </ul> -<h2>Other <code><abbr>tz</abbr></code> binary file readers</h2> +<h2 id="binary">Other <code><abbr>tz</abbr></code> binary file readers</h2> <ul> <li>The <a href="https://www.gnu.org/software/libc/"><abbr>GNU</abbr> C @@ -439,7 +440,7 @@ package contains <a href="https://www.haskell.org">Haskell</a> code that parses and uses <code><abbr>tz</abbr></code> binary data. It is freely available under a <abbr>BSD</abbr>-style license.</li> </ul> -<h2>Other <code><abbr>tz</abbr></code>-based time zone software</h2> +<h2 id="software">Other <code><abbr>tz</abbr></code>-based time zone software</h2> <ul> <li><a href="https://foxclocks.org">FoxClocks</a> is an extension for <a href="https://www.google.com/chrome/">Google @@ -496,7 +497,7 @@ an <abbr>OS X</abbr> program. Its developers <a href="http://veladg.com/tzoffer.html">offer free licenses</a> to <code><abbr>tz</abbr></code> contributors.</li> </ul> -<h2>Other time zone databases</h2> +<h2 id="other-dbs">Other time zone databases</h2> <ul> <li><a href="http://www.astro.com/atlas">Time-zone Atlas</a> is Astrodienst's Web version of Shanks and Pottenger's @@ -525,7 +526,7 @@ Schedules Information Manual</a> of the International Air Transport Association gives current time zone rules for airports served by commercial aviation.</li> </ul> -<h2>Maps</h2> +<h2 id="maps">Maps</h2> <ul> <li>The <a href="https://www.cia.gov/index.html">United States Central Intelligence Agency (<abbr @@ -552,7 +553,7 @@ much is time wrong around the world?</a> maps the difference between mean solar and standard time, highlighting areas such as western China where the two differ greatly. It's a bit out of date, unfortunately.</li> </ul> -<h2>Time zone boundaries</h2> +<h2 id="boundaries">Time zone boundaries</h2> <ul> <li><a href="http://efele.net/maps/tz/"><abbr>TZ</abbr> timezones maps</a> contains <a @@ -589,7 +590,7 @@ for land and territorial waters only). A captain can change ship's clocks any time after entering a new time zone; midnight changes are common.</li> </ul> -<h2>Civil time concepts and history</h2> +<h2 id="civil">Civil time concepts and history</h2> <ul> <li><a href="http://physics.nist.gov/time">A Walk through Time</a> @@ -609,7 +610,7 @@ time zone boundary.</li> <li><a href="http://statoids.com/tconcept.html">Basic Time Zone Concepts</a> discusses terminological issues behind time zones.</li> </ul> -<h2>National histories of legal time</h2> +<h2 id="national">National histories of legal time</h2> <dl> <dt>Australia</dt> <dd>The Parliamentary Library has commissioned a <a @@ -679,7 +680,7 @@ of Summer time dates</a>.</dd> href="https://www.transportation.gov/regulations/recent-time-zone-proceedings">Recent Time Zone Proceedings</a> lists changes to time zone boundaries.</dd> </dl> -<h2>Precision timekeeping</h2> +<h2 id="precision">Precision timekeeping</h2> <ul> <li><a href="http://literature.agilent.com/litweb/pdf/5965-7984E.pdf">The @@ -752,7 +753,7 @@ might be redefined without Leap Seconds</a> gives pointers on this contentious issue.</li> </ul> -<h2>Time notation</h2> +<h2 id="notation">Time notation</h2> <ul> <li>The <a href="http://cldr.unicode.org">Unicode Common Locale Data Repository (<abbr>CLDR</abbr>) Project</a> has localizations for time @@ -826,7 +827,7 @@ any future changes to the rules. One should never set local time is nine hours ahead of <abbr>UTC</abbr> and the time zone is called "<abbr>GMT</abbr>".</li> </ul> -<h2>See also</h2> +<h2 id="see-also">See also</h2> <ul> <li><a href="tz-art.htm">Time and the Arts</a></li> </ul> -- 2.7.4

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Adapting localtime.c
by Carsten Larsen Oct. 10, 2016

Oct. 10, 2016

Hello list I am trying to adapt the tz code to a local system without any timezone database (AmigaOS). I got the code up and running and everything seems to work as intended. But one thing about the code puzzles me. I need to implement "time_t time(time_t *p)" which is the very last part of localtime.c. Should this code return time as local time or as GMT time ? Because I cannot get the time calculations to work properly. I use tzsetwall() to guess the timezone from the systems locale zone information (GMT+1, etc) and tzset() to load timezone from the TZ environment variable. Should "time_t time(time_t *p)" try to compensate if lclptr is set, or should it always just return the plain system time? I hope someone knows the answer and also thank you for any clarifications on this issue. Kind regards Carsten Larsen

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