1 News for the tz database
3 Release 2020a - 2020-04-23 16:03:47 -0700
6 Morocco springs forward on 2020-05-31, not 2020-05-24.
7 Canada's Yukon advanced to -07 year-round on 2020-03-08.
8 America/Nuuk renamed from America/Godthab.
9 zic now supports expiration dates for leap second lists.
11 Changes to future timestamps
13 Morocco's second spring-forward transition in 2020 will be May 31,
14 not May 24 as predicted earlier. (Thanks to Semlali Naoufal.)
15 Adjust future-year predictions to use the first Sunday after the
16 day after Ramadan, not the first Sunday after Ramadan.
18 Canada's Yukon, represented by America/Whitehorse and
19 America/Dawson, advanced to -07 year-round, beginning with its
20 spring-forward transition on 2020-03-08, and will not fall back on
21 2020-11-01. Although a government press release calls this
22 "permanent Pacific Daylight Saving Time", we prefer MST for
23 consistency with nearby Dawson Creek, Creston, and Fort Nelson.
24 (Thanks to Tim Parenti.)
26 Changes to past timestamps
28 Shanghai observed DST in 1919. (Thanks to Phake Nick.)
30 Changes to timezone identifiers
32 To reflect current usage in English better, America/Godthab has
33 been renamed to America/Nuuk. A backwards-compatibility link
34 remains for the old name.
38 localtime.c no longer mishandles timestamps after the last
39 transition in a TZif file with leap seconds and with daylight
40 saving time transitions projected into the indefinite future.
41 For example, with TZ='America/Los_Angeles' with leap seconds,
42 zdump formerly reported a DST transition on 2038-03-14
43 from 01:59:32.999... to 02:59:33 instead of the correct transition
44 from 01:59:59.999... to 03:00:00.
46 zic -L now supports an Expires line in the leapseconds file, and
47 truncates the TZif output accordingly. This propagates leap
48 second expiration information into the TZif file, and avoids the
49 abovementioned localtime.c bug as well as similar bugs present in
50 many client implementations. If no Expires line is present, zic
51 -L instead truncates the TZif output based on the #expires comment
52 present in leapseconds files distributed by tzdb 2018f and later;
53 however, this usage is obsolescent. For now, the distributed
54 leapseconds file has an Expires line that is commented out, so
55 that the file can be fed to older versions of zic which ignore the
56 commented-out line. Future tzdb distributions are planned to
57 contain a leapseconds file with an Expires line.
59 The configuration macros HAVE_TZNAME and USG_COMPAT should now be
60 set to 1 if the system library supports the feature, and 2 if not.
61 As before, these macros are nonzero if tzcode should support the
62 feature, zero otherwise.
64 The configuration macro ALTZONE now has the same values with the
65 same meaning as HAVE_TZNAME and USG_COMPAT.
67 The code's defense against CRLF in leap-seconds.list is now
68 portable to POSIX awk. (Problem reported by Deborah Goldsmith.)
70 Although the undocumented tzsetwall function is not changed in
71 this release, it is now deprecated in preparation for removal in
72 future releases. Due to POSIX requirements, tzsetwall has not
73 worked for some time. Any code that uses it should instead use
74 tzalloc(NULL) or, if portability trumps thread-safety, should
75 unset the TZ environment variable.
79 The Îles-de-la-Madeleine and the Listuguj reserve are noted as
80 following America/Halifax, and comments about Yukon's "south" and
81 "north" have been corrected to say "east" and "west". (Thanks to
85 Release 2019c - 2019-09-11 08:59:48 -0700
88 Fiji observes DST from 2019-11-10 to 2020-01-12.
89 Norfolk Island starts observing Australian-style DST.
91 Changes to future timestamps
93 Fiji's next DST transitions will be 2019-11-10 and 2020-01-12
94 instead of 2019-11-03 and 2020-01-19. (Thanks to Raymond Kumar.)
95 Adjust future guesses accordingly.
97 Norfolk Island will observe Australian-style DST starting in
98 spring 2019. The first transition is on 2019-10-06. (Thanks to
99 Kyle Czech and Michael Deckers.)
101 Changes to past timestamps
103 Many corrections to time in Turkey from 1940 through 1985.
104 (Thanks to Oya Vulaş via Alois Treindl, and to Kıvanç Yazan.)
106 The Norfolk Island 1975-03-02 transition was at 02:00 standard
107 time, not 02:00 DST. (Thanks to Michael Deckers.)
109 South Korea observed DST from 1948 through 1951. Although this
110 info was supposed to appear in release 2014j, a typo inadvertently
111 suppressed the change. (Thanks to Alois Treindl.)
113 Detroit observed DST in 1967 and 1968 following the US DST rules,
114 except that its 1967 DST began on June 14 at 00:01. (Thanks to
115 Alois Treindl for pointing out that the old data entries were
118 Fix several errors in pre-1970 transitions in Perry County, IN.
119 (Thanks to Alois Triendl for pointing out the 1967/9 errors.)
121 Edmonton did not observe DST in 1967 or 1969. In 1946 Vancouver
122 ended DST on 09-29 not 10-13, and Vienna ended DST on 10-07 not
123 10-06. In 1945 Königsberg (now Kaliningrad) switched from +01/+02
124 to +02/+03 on 04-10 not 01-01, and its +02/+03 is abbreviated
125 EET/EEST, not CET/CEST. (Thanks to Alois Triendl.) In 1946
126 Königsberg switched to +03 on 04-07 not 01-01.
128 In 1946 Louisville switched from CST to CDT on 04-28 at 00:01, not
129 01-01 at 00:00. (Thanks to Alois Treindl and Michael Deckers.)
130 Also, it switched from CST to CDT on 1950-04-30, not 1947-04-27.
132 The 1892-05-01 transition in Brussels was at 00:17:30, not at noon.
133 (Thanks to Michael Deckers.)
135 Changes to past time zone abbreviations and DST flags
137 Hong Kong Winter Time, observed from 1941-10-01 to 1941-12-25,
138 is now flagged as DST and is abbreviated HKWT not HKT.
142 leapseconds.awk now relies only on its input data, rather than
143 also relying on its comments. (Inspired by code from Dennis
144 Ferguson and Chris Woodbury.)
146 The code now defends against CRLFs in leap-seconds.list.
147 (Thanks to Brian Inglis and Chris Woodbury.)
149 Changes to documentation and commentary
151 theory.html discusses leap seconds. (Thanks to Steve Summit.)
153 Nashville's newspapers dueled about the time of day in the 1950s.
154 (Thanks to John Seigenthaler.)
156 Liechtenstein observed Swiss DST in 1941/2.
157 (Thanks to Alois Treindl.)
160 Release 2019b - 2019-07-01 00:09:53 -0700
163 Brazil no longer observes DST.
164 'zic -b slim' outputs smaller TZif files; please try it out.
165 Palestine's 2019 spring-forward transition was on 03-29, not 03-30.
167 Changes to future timestamps
169 Brazil has canceled DST and will stay on standard time indefinitely.
170 (Thanks to Steffen Thorsen, Marcus Diniz, and Daniel Soares de
173 Predictions for Morocco now go through 2087 instead of 2037, to
174 work around a problem on newlib when using TZif files output by
175 zic 2019a or earlier. (Problem reported by David Gauchard.)
177 Changes to past and future timestamps
179 Palestine's 2019 spring transition was 03-29 at 00:00, not 03-30
180 at 01:00. (Thanks to Sharef Mustafa and Even Scharning.) Guess
181 future transitions to be March's last Friday at 00:00.
183 Changes to past timestamps
185 Hong Kong's 1941-06-15 spring-forward transition was at 03:00, not
186 03:30. Its 1945 transition from JST to HKT was on 11-18 at 02:00,
187 not 09-15 at 00:00. In 1946 its spring-forward transition was on
188 04-21 at 00:00, not the previous day at 03:30. From 1946 through
189 1952 its fall-back transitions occurred at 04:30, not at 03:30.
190 In 1947 its fall-back transition was on 11-30, not 12-30.
193 Changes to past time zone abbreviations
195 Italy's 1866 transition to Rome Mean Time was on December 12, not
196 September 22. This affects only the time zone abbreviation for
197 Europe/Rome between those dates. (Thanks to Stephen Trainor and
200 Changes affecting metadata only
202 Add info about the Crimea situation in zone1970.tab and zone.tab.
203 (Problem reported by Serhii Demediuk.)
207 zic's new -b option supports a way to control data bloat and to
208 test for year-2038 bugs in software that reads TZif files.
209 'zic -b fat' and 'zic -b slim' generate larger and smaller output;
210 for example, changing from fat to slim shrinks the Europe/London
211 file from 3648 to 1599 bytes, saving about 56%. Fat and slim
212 files represent the same set of timestamps and use the same TZif
213 format as documented in tzfile(5) and in Internet RFC 8536.
214 Fat format attempts to work around bugs or incompatibilities in
215 older software, notably software that mishandles 64-bit TZif data
216 or uses obsolete TZ strings like "EET-2EEST" that lack DST rules.
217 Slim format is more efficient and does not work around 64-bit bugs
218 or obsolete TZ strings. Currently zic defaults to fat format
219 unless you compile with -DZIC_BLOAT_DEFAULT=\"slim\"; this
220 out-of-the-box default is intended to change in future releases
221 as the buggy software often mishandles timestamps anyway.
223 zic no longer treats a set of rules ending in 2037 specially.
224 Previously, zic assumed that such a ruleset meant that future
225 timestamps could not be predicted, and therefore omitted a
226 POSIX-like TZ string in the TZif output. The old behavior is no
227 longer needed for current tzdata, and caused problems with newlib
228 when used with older tzdata (reported by David Gauchard).
230 zic no longer generates some artifact transitions. For example,
231 Europe/London no longer has a no-op transition in January 1996.
233 Changes to build procedure
235 tzdata.zi now assumes zic 2017c or later. This shrinks tzdata.zi
238 Changes to documentation and commentary
240 The Makefile now documents the POSIXRULES macro as being obsolete,
241 and similarly, zic's -p POSIXRULES option is now documented as
242 being obsolete. Although the POSIXRULES feature still exists and
243 works as before, in practice it is rarely used for its intended
244 purpose, and it does not work either in the default reference
245 implementation (for timestamps after 2037) or in common
246 implementations such as GNU/Linux (for contemporary timestamps).
247 Since POSIXRULES was designed primarily as a temporary transition
248 facility for System V platforms that died off decades ago, it is
249 being decommissioned rather than institutionalized.
251 New info on Bonin Islands and Marcus (thanks to Wakaba and Phake Nick).
254 Release 2019a - 2019-03-25 22:01:33 -0700
257 Palestine "springs forward" on 2019-03-30 instead of 2019-03-23.
258 Metlakatla "fell back" to rejoin Alaska Time on 2019-01-20 at 02:00.
260 Changes to past and future timestamps
262 Palestine will not start DST until 2019-03-30, instead of 2019-03-23 as
263 previously predicted. Adjust our prediction by guessing that spring
264 transitions will be between 24 and 30 March, which matches recent practice
265 since 2016. (Thanks to Even Scharning and Tim Parenti.)
267 Metlakatla ended its observance of Pacific standard time,
268 rejoining Alaska Time, on 2019-01-20 at 02:00. (Thanks to Ryan
269 Stanley and Tim Parenti.)
271 Changes to past timestamps
273 Israel observed DST in 1980 (08-02/09-13) and 1984 (05-05/08-25).
274 (Thanks to Alois Treindl and Isaac Starkman.)
276 Changes to time zone abbreviations
278 Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
279 of being a separate zone that generates the abbreviation "UCT",
280 which nowadays is typically a typo. (Problem reported by Isiah
285 zic now has an -r option to limit the time range of output data.
286 For example, 'zic -r @1000000000' limits the output data to
287 timestamps starting 1000000000 seconds after the Epoch.
288 This helps shrink output size and can be useful for applications
289 not needing the full timestamp history, such as TZDIST truncation;
290 see Internet RFC 8536 section 5.1. (Inspired by a feature request
291 from Christopher Wong, helped along by bug reports from Wong and
294 Changes to documentation
296 Mention Internet RFC 8536 (February 2019), which documents TZif.
298 tz-link.html now cites tzdata-meta
299 <https://tzdata-meta.timtimeonline.com/>.
302 Release 2018i - 2018-12-30 11:05:43 -0800
305 São Tomé and Príncipe switches from +01 to +00 on 2019-01-01.
307 Changes to future timestamps
309 Due to a change in government, São Tomé and Príncipe switches back
310 from +01 to +00 on 2019-01-01 at 02:00. (Thanks to Vadim
311 Nasardinov and Michael Deckers.)
314 Release 2018h - 2018-12-23 17:59:32 -0800
317 Qyzylorda, Kazakhstan moved from +06 to +05 on 2018-12-21.
318 New zone Asia/Qostanay because Qostanay, Kazakhstan didn't move.
319 Metlakatla, Alaska observes PST this winter only.
320 Guess Morocco will continue to adjust clocks around Ramadan.
321 Add predictions for Iran from 2038 through 2090.
323 Changes to future timestamps
325 Guess that Morocco will continue to fall back just before and
326 spring forward just after Ramadan, the practice since 2012.
327 (Thanks to Maamar Abdelkader.) This means Morocco will observe
328 negative DST during Ramadan in main and vanguard formats, and in
329 rearguard format it stays in the +00 timezone and observes
330 ordinary DST in all months other than Ramadan. As before, extend
331 this guesswork to the year 2037. As a consequence, Morocco is
332 scheduled to observe three DST transitions in some Gregorian years
333 (e.g., 2033) due to the mismatch between the Gregorian and Islamic
336 The table of exact transitions for Iranian DST has been extended.
337 It formerly cut off before the year 2038 in a nod to 32-bit time_t.
338 It now cuts off before 2091 as there is doubt about how the Persian
339 calendar will treat 2091. This change predicts DST transitions in
340 2038-9, 2042-3, and 2046-7 to occur one day later than previously
341 predicted. As before, post-cutoff transitions are approximated.
343 Changes to past and future timestamps
345 Qyzylorda (aka Kyzylorda) oblast in Kazakhstan moved from +06 to
346 +05 on 2018-12-21. This is a zone split as Qostanay (aka
347 Kostanay) did not switch, so create a zone Asia/Qostanay.
349 Metlakatla moved from Alaska to Pacific standard time on 2018-11-04.
350 It did not change clocks that day and remains on -08 this winter.
351 (Thanks to Ryan Stanley.) It will revert to the usual Alaska
352 rules next spring, so this change affects only timestamps
353 from 2018-11-04 through 2019-03-10.
355 Change to past timestamps
357 Kwajalein's 1993-08-20 transition from -12 to +12 was at 24:00,
358 not 00:00. I transcribed the time incorrectly from Shanks.
359 (Thanks to Phake Nick.)
361 Nauru's 1979 transition was on 02-10 at 02:00, not 05-01 at 00:00.
362 (Thanks to Phake Nick.)
364 Guam observed DST irregularly from 1959 through 1977.
365 (Thanks to Phake Nick.)
367 Hong Kong observed DST in 1941 starting 06-15 (not 04-01), then on
368 10-01 changed standard time to +08:30 (not +08). Its transition
369 back to +08 after WWII was on 1945-09-15, not the previous day.
370 Its 1904-10-30 change took effect at 01:00 +08 (not 00:00 LMT).
371 (Thanks to Phake Nick, Steve Allen, and Joseph Myers.) Also,
372 its 1952 fallback was on 11-02 (not 10-25).
374 This release contains many changes to timestamps before 1946 due
375 to Japanese possession or occupation of Pacific/Chuuk,
376 Pacific/Guam, Pacific/Kosrae, Pacific/Kwajalein, Pacific/Majuro,
377 Pacific/Nauru, Pacific/Palau, and Pacific/Pohnpei.
378 (Thanks to Phake Nick.)
380 Assume that the Spanish East Indies was like the Philippines and
381 observed American time until the end of 1844. This affects
382 Pacific/Chuuk, Pacific/Kosrae, Pacific/Palau, and Pacific/Pohnpei.
384 Changes to past tm_isdst flags
386 For the recent Morocco change, the tm_isdst flag should be 1 from
387 2018-10-27 00:00 to 2018-10-28 03:00. (Thanks to Michael Deckers.)
388 Give a URL to the official decree. (Thanks to Matt Johnson.)
391 Release 2018g - 2018-10-26 22:22:45 -0700
394 Morocco switches to permanent +01 on 2018-10-28.
396 Changes to future timestamps
398 Morocco switches from +00/+01 to permanent +01 effective 2018-10-28,
399 so its clocks will not fall back as previously scheduled.
400 (Thanks to Mohamed Essedik Najd and Brian Inglis.)
404 When generating TZif files with leap seconds, zic no longer uses a
405 format that trips up older 32-bit clients, fixing a bug introduced
406 in 2018f. (Reported by Daniel Fischer.) Also, the zic workaround
407 for QTBUG-53071 now also works for TZif files with leap seconds.
409 The translator to rearguard format now rewrites the line
410 "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
411 "Rule Japan 1948 1951 - Sep Sun>=9 1:00 0 S".
412 This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
413 and earlier. (Reported by Christos Zoulas.)
415 Changes to past time zone abbreviations
417 Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
418 This reverts to 2011h, as the abbreviation change in 2011i was
421 Changes to documentation
423 tzfile.5 has new sections on interoperability issues.
426 Release 2018f - 2018-10-18 00:14:18 -0700
429 Volgograd moves from +03 to +04 on 2018-10-28.
430 Fiji ends DST 2019-01-13, not 2019-01-20.
431 Most of Chile changes DST dates, effective 2019-04-06.
433 Changes to future timestamps
435 Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
436 (Thanks to Alexander Fetisov and Stepan Golosunov.)
438 Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
439 predicted. (Thanks to Raymond Kumar.) Adjust future predictions
442 Most of Chile will end DST on the first Saturday in April at 24:00 mainland
443 time, and resume DST on the first Saturday in September at 24:00 mainland
444 time. The changes are effective from 2019-04-06, and do not affect the
445 Magallanes region modeled by America/Punta_Arenas. (Thanks to Juan Correa
446 and Tim Parenti.) Adjust future predictions accordingly.
448 Changes to past timestamps
450 The 2018-05-05 North Korea 30-minute time zone change took place
451 at 23:30 the previous day, not at 00:00 that day.
453 China's 1988 spring-forward transition was on April 17, not
454 April 10. Its DST transitions in 1986/91 were at 02:00, not 00:00.
457 Fix several issues for Macau before 1992. Macau's pre-1904 LMT
458 was off by 10 s. Macau switched to +08 in 1904 not 1912, and
459 temporarily switched to +09/+10 during World War II. Macau
460 observed DST in 1942/79, not 1961/80, and there were several
461 errors for transition times and dates. (Thanks to P Chan.)
463 The 1948-1951 fallback transitions in Japan were at 25:00 on
464 September's second Saturday, not at 24:00. (Thanks to Phake Nick.)
465 zic turns this into 01:00 on the day after September's second
466 Saturday, which is the best that POSIX or C platforms can do.
468 Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
469 paper by Li Yu, replacing more-questionable data from Shanks.
471 Changes to time zone abbreviations
473 Use "PST" and "PDT" for Philippine time. (Thanks to Paul Goyette.)
477 zic now always generates TZif files where time type 0 is used for
478 timestamps before the first transition. This simplifies the
479 reading of TZif files and should not affect behavior of existing
480 TZif readers because the same set of time types is used; only
481 their internal indexes may have changed. This affects only the
482 legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
483 EET, which previously used nonzero types for these timestamps.
485 Because of the type 0 change, zic no longer outputs a dummy
486 transition at time -2**59 (before the Big Bang), as clients should
487 no longer need this to handle historical timestamps correctly.
488 This reverts a change introduced in 2013d and shrinks most TZif
489 files by a few bytes.
491 zic now supports negative time-of-day in Rule and Leap lines, e.g.,
492 "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
493 occurs at 18:00 on the Saturday before the last Sunday in April.
494 This behavior was documented in 2018a but the code did not
495 entirely match the documentation.
497 localtime.c no longer requires at least one time type in TZif
498 files that lack transitions or have a POSIX-style TZ string. This
499 future-proofs the code against possible future extensions to the
500 format that would allow TZif files with POSIX-style TZ strings and
501 without transitions or time types.
503 A read-access subscript error in localtime.c has been fixed.
504 It could occur only in TZif files with timecnt == 0, something that
505 does not happen in practice now but could happen in future versions.
507 localtime.c no longer ignores TZif POSIX-style TZ strings that
508 specify only standard time. Instead, these TZ strings now
509 override the default time type for timestamps after the last
510 transition (or for all timestamps if there are no transitions),
511 just as DST strings specifying DST have always done.
513 leapseconds.awk now outputs "#updated" and "#expires" comments,
514 and supports leap seconds at the ends of months other than June
515 and December. (Inspired by suggestions from Chris Woodbury.)
517 Changes to documentation
519 New restrictions: A Rule name must start with a character that
520 is neither an ASCII digit nor "-" nor "+", and an unquoted name
521 should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
522 The latter restriction makes room for future extensions (a
523 possibility noted by Tom Lane).
525 tzfile.5 now documents what time types apply before the first and
526 after the last transition, if any.
528 Documentation now uses the spelling "timezone" for a TZ setting
529 that determines timestamp history, and "time zone" for a
530 geographic region currently sharing the same standard time.
532 The name "TZif" is now used for the tz binary data format.
534 tz-link.htm now mentions the A0 TimeZone Migration utilities.
535 (Thanks to Aldrin Martoq for the link.)
537 Changes to build procedure
539 New 'make' target 'rearguard_tarballs' to build the rearguard
540 tarball only. This is a convenience on platforms that lack lzip
541 if you want to build the rearguard tarball. (Problem reported by
544 tzdata.zi is now more stable from release to release. (Problem
545 noted by Tom Lane.) It is also a bit shorter.
547 tzdata.zi now can contain comment lines documenting configuration
548 information, such as which data format was selected, which input
549 files were used, and how leap seconds are treated. (Problems
550 noted by Lester Caine and Brian Inglis.) If the Makefile defaults
551 are used these comment lines are absent, for backward
552 compatibility. A redistributor intending to alter its copy of the
553 files should also append "-LABEL" to the 'version' file's first
554 line, where "LABEL" identifies the redistributor's change.
557 Release 2018e - 2018-05-01 23:42:51 -0700
561 North Korea switches back to +09 on 2018-05-05.
562 The main format uses negative DST again, for Ireland etc.
563 'make tarballs' now also builds a rearguard tarball.
564 New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
566 Changes to past and future timestamps
568 North Korea switches back from +0830 to +09 on 2018-05-05.
569 (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
572 Bring back the negative-DST changes of 2018a, except be more
573 compatible with data parsers that do not support negative DST.
574 Also, this now affects historical timestamps in Namibia and the
575 former Czechoslovakia, not just Ireland. The main format now uses
576 negative DST to model timestamps in Europe/Dublin (from 1971 on),
577 Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This
578 does not affect UT offsets, only time zone abbreviations and the
579 tm_isdst flag. Also, this does not affect rearguard or vanguard
580 formats; effectively the main format now uses vanguard instead of
581 rearguard format. Data parsers that do not support negative DST
582 can still use data from the rearguard tarball described below.
584 Changes to build procedure
586 The command 'make tarballs' now also builds the tarball
587 tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
588 except that it uses rearguard format intended for trailing-edge
591 Changes to data format and to code
593 The SAVE column of Rule and Zone lines can now have an 's' or 'd'
594 suffix, which specifies whether the adjusted time is standard time
595 or daylight saving time. If no suffix is given, daylight saving
596 time is used if and only if the SAVE column is nonzero; this is
597 the longstanding behavior. Although this new feature is not used
598 in tzdata, it could be used to specify the legal time in Namibia
599 1994-2017, as opposed to the popular time (see below).
601 Changes to past timestamps
603 From 1994 through 2017 Namibia observed DST in winter, not summer.
604 That is, it used negative DST, as Ireland still does. This change
605 does not affect UTC offsets; it affects only the tm_isdst flag and
606 the abbreviation used during summer, which is now CAT, not WAST.
607 Although (as noted by Michael Deckers) summer and winter time were
608 both simply called "standard time" in Namibian law, in common
609 practice winter time was considered to be DST (as noted by Stephen
610 Colebourne). The full effect of this change is only in vanguard
611 and main format; in rearguard format, the tm_isdst flag is still
612 zero in winter and nonzero in summer.
614 In 1946/7 Czechoslovakia also observed negative DST in winter.
615 The full effect of this change is only in vanguard and main
616 formats; in rearguard format, it is modeled as plain GMT without
617 daylight saving. Also, the dates of some 1944/5 DST transitions
618 in Czechoslovakia have been changed.
621 Release 2018d - 2018-03-22 07:05:46 -0700
625 Palestine starts DST a week earlier in 2018.
626 Add support for vanguard and rearguard data consumers.
627 Add subsecond precision to source data format, though not to data.
629 Changes to future timestamps
631 In 2018, Palestine starts DST on March 24, not March 31.
632 Adjust future predictions accordingly. (Thanks to Sharef Mustafa.)
634 Changes to past and future timestamps
636 Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
637 at 04:00. (Thanks to Steffen Thorsen.)
639 Changes to past timestamps
641 Historical transitions for Uruguay, represented by
642 America/Montevideo, have been updated per official legal documents,
643 replacing previous data mainly originating from the inventions of
644 Shanks & Pottenger. This has resulted in adjustments ranging from
645 30 to 90 minutes in either direction over at least two dozen
646 distinct periods ranging from one day to several years in length.
647 A mere handful of pre-1991 transitions are unaffected; data since
648 then has come from more reliable contemporaneous reporting. These
649 changes affect various timestamps in 1920-1923, 1936, 1939,
650 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
651 Additionally, Uruguay's pre-standard-time UT offset has been
652 adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
653 match the location of the Observatory of the National Meteorological
654 Institute in Montevideo.
655 (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
657 Enderbury and Kiritimati skipped New Year's Eve 1994, not
658 New Year's Day 1995. (Thanks to Kerry Shetline.)
660 Fix the 1912-01-01 transition for Portugal and its colonies.
661 This transition was at 00:00 according to the new UT offset, not
662 according to the old one. Also assume that Cape Verde switched on
663 the same date as the rest, not in 1907. This affects
664 Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
665 Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
666 (Thanks to Michael Deckers.)
668 Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
671 Changes to past time zone abbreviations
673 MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There
674 is no clock change associated with the transition.
676 Changes to build procedure
678 The new DATAFORM macro in the Makefile lets the installer choose
679 among three source data formats. The idea is to lessen downstream
680 disruption when data formats are improved.
682 * DATAFORM=vanguard installs from the latest, bleeding-edge
683 format. DATAFORM=main (the default) installs from the format
684 used in the 'africa' etc. files. DATAFORM=rearguard installs
685 from a trailing-edge format. Eventually, elements of today's
686 vanguard format should move to the main format, and similarly
687 the main format's features should eventually move to the
690 * In the current version, the main and rearguard formats are
691 identical and match that of 2018c, so this change does not
692 affect default behavior. The vanguard format currently contains
693 one feature not in the main format: negative SAVE values. This
694 improves support for Ireland, which uses Irish Standard Time
695 (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has
696 supported negative SAVE values for decades, and this feature
697 should move to the main format soon. However, it will not move
698 to the rearguard format for quite some time because some
699 downstream parsers do not support it.
701 * The build procedure constructs three files vanguard.zi, main.zi,
702 and rearguard.zi, one for each format. Although the files
703 represent essentially the same data, they may have minor
704 discrepancies that users are not likely to notice. The files
705 are intended for downstream data consumers and are not
706 installed. Zoneinfo parsers that do not support negative SAVE values
707 should start using rearguard.zi, so that they will be unaffected
708 when the negative-DST feature moves from vanguard to main.
709 Bleeding-edge Zoneinfo parsers that support the new features
710 already can use vanguard.zi; in this respect, current tzcode is
713 The Makefile should now be safe for parallelized builds, and 'make
714 -j to2050new.tzs' is now much faster on a multiprocessor host
717 When built with -DSUPPRESS_TZDIR, the tzcode library no longer
718 prepends TZDIR/ to file names that do not begin with '/'. This is
719 not recommended for general use, due to its security implications.
720 (From a suggestion by Manuela Friedrich.)
724 zic now accepts subsecond precision in expressions like
725 00:19:32.13, which is approximately the legal time of the
726 Netherlands from 1835 to 1937. However, because it is
727 questionable whether the few recorded uses of non-integer offsets
728 had subsecond precision in practice, there are no plans for tzdata
729 to use this feature. (Thanks to Steve Allen for pointing out
730 the limitations of historical data in this area.)
732 The code is a bit more portable to MS-Windows. Installers can
733 compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
734 reserve identifiers like 'localtime'. (Thanks to Manuela
737 Changes to documentation and commentary
739 theory.html now outlines tzdb's extensions to POSIX's model for
740 civil time, and has a section "POSIX features no longer needed"
741 that lists POSIX API components that are now vestigial.
742 (From suggestions by Steve Summit.) It also better distinguishes
743 time zones from tz regions. (From a suggestion by Guy Harris.)
745 Commentary is now more consistent about using the phrase "daylight
746 saving time", to match the C name tm_isdst. Daylight saving time
747 need not occur in summer, and need not have a positive offset from
750 Commentary about historical transitions in Uruguay has been expanded
751 with links to many relevant legal documents.
752 (Thanks to Tim Parenti.)
754 Commentary now uses some non-ASCII characters with Unicode value
755 less than U+0100, as they can be useful and should work even with
756 older editors such as XEmacs.
759 Release 2018c - 2018-01-22 23:00:44 -0800
762 Revert Irish changes that relied on negative SAVE values.
766 Revert the 2018a change to Europe/Dublin. As before, this change
767 does not affect UT offsets or abbreviations; it affects only
768 whether timestamps are considered to be standard time or
769 daylight-saving time, as expressed in the tm_isdst flag of C's
770 struct tm type. This reversion is intended to be a temporary
771 workaround for problems discovered with downstream uses of
772 releases 2018a and 2018b, which implemented Irish time by using
773 negative SAVE values in the Eire rules of the 'europe' file.
774 Although negative SAVE values have been part of tzcode for many
775 years and are supported by many platforms, they were not
776 documented before 2018a and ICU and OpenJDK do not currently
777 support them. A mechanism to export data to platforms lacking
778 support for negative DST is planned to be developed before the
779 change is reapplied. (Problems reported by Deborah Goldsmith and
782 Changes to past timestamps
784 Japanese DST transitions (1948-1951) were Sundays at 00:00, not
785 Saturdays or Sundays at 02:00. (Thanks to Takayuki Nikai.)
787 Changes to build procedure
789 The build procedure now works around mawk 1.3.3's lack of support
790 for character class expressions. (Problem reported by Ohyama.)
793 Release 2018b - 2018-01-17 23:24:48 -0800
796 Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
798 Changes to build procedure
800 The distribution now contains the file 'pacificnew' again.
801 This file was inadvertantly omitted in the 2018a distribution.
802 (Problem reported by Matias Fonzo.)
805 Release 2018a - 2018-01-12 22:29:21 -0800
808 São Tomé and Príncipe switched from +00 to +01.
809 Brazil's DST will now start on November's first Sunday.
810 Ireland's standard time is now in the summer, not the winter.
811 Use Debian-style installation locations, instead of 4.3BSD-style.
814 Changes to past and future timestamps
816 São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
817 01:00. (Thanks to Steffen Thorsen and Michael Deckers.)
819 Changes to future timestamps
821 Starting in 2018 southern Brazil will begin DST on November's
822 first Sunday instead of October's third Sunday. (Thanks to
825 Changes to past timestamps
827 A discrepancy of 4 s in timestamps before 1931 in South Sudan has
828 been corrected. The 'backzone' and 'zone.tab' files did not agree
829 with the 'africa' and 'zone1970.tab' files. (Problem reported by
832 The abbreviation invented for Bolivia Summer Time (1931-2) is now
833 BST instead of BOST, to be more consistent with the convention
834 used for Latvian Summer Time (1918-9) and for British Summer Time.
838 Change Europe/Dublin so that it observes Irish Standard Time (UT
839 +01) in summer and GMT (as negative daylight-saving) in winter,
840 instead of observing standard time (GMT) in winter and Irish
841 Summer Time (UT +01) in summer. This change does not affect UT
842 offsets or abbreviations; it affects only whether timestamps are
843 considered to be standard time or daylight-saving time, as
844 expressed in the tm_isdst flag of C's struct tm type.
845 (Discrepancy noted by Derick Rethans.)
847 Changes to build procedure
849 The default installation locations have been changed to mostly
850 match Debian circa 2017, instead of being designed as an add-on to
851 4.3BSD circa 1986. This affects the Makefile macros TOPDIR,
852 TZDIR, MANDIR, and LIBDIR. New Makefile macros TZDEFAULT, USRDIR,
853 USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
854 locations more precisely. (This responds to suggestions from
855 Brian Inglis and from Steve Summit.)
857 The default installation procedure no longer creates the
858 backward-compatibility link US/Pacific-New, which causes
859 confusion during user setup (e.g., see Debian bug 815200).
860 Use 'make BACKWARD="backward pacificnew"' to create the link
861 anyway, for now. Eventually we plan to remove the link entirely.
863 tzdata.zi now contains a version-number comment.
864 (Suggested by Tom Lane.)
866 The Makefile now quotes values like BACKWARD more carefully when
867 passing them to the shell. (Problem reported by Zefram.)
869 Builders no longer need to specify -DHAVE_SNPRINTF on platforms
870 that have snprintf and use pre-C99 compilers. (Problem reported
875 zic has a new option -t FILE that specifies the location of the
876 file that determines local time when TZ is unset. The default for
877 this location can be configured via the new TZDEFAULT makefile
878 macro, which defaults to /etc/localtime.
880 Diagnostics and commentary now distinguish UT from UTC more
881 carefully; see theory.html for more information about UT vs UTC.
883 zic has been ported to GCC 8's -Wstringop-truncation option.
884 (Problem reported by Martin Sebor.)
886 Changes to documentation and commentary
888 The zic man page now documents the longstanding behavior that
889 times and years can be out of the usual range, with negative times
890 counting backwards from midnight and with year 0 preceding year 1.
891 (Problem reported by Michael Deckers.)
893 The theory.html file now mentions the POSIX limit of six chars
894 per abbreviation, and lists alphabetic abbreviations used.
896 The files tz-art.htm and tz-link.htm have been renamed to
897 tz-art.html and tz-link.html, respectively, for consistency with
898 other file names and to simplify web server configuration.
901 Release 2017c - 2017-10-20 14:49:34 -0700
904 Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
905 Fiji ends DST 2018-01-14, not 2018-01-21.
906 Namibia switches from +01/+02 to +02 on 2018-04-01.
907 Sudan switches from +03 to +02 on 2017-11-01.
908 Tonga likely switches from +13/+14 to +13 on 2017-11-05.
909 Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
910 A new file tzdata.zi now holds a small text copy of all data.
911 The zic input format has been regularized slightly.
913 Changes to future timestamps
915 Northern Cyprus has decided to resume EU rules starting
916 2017-10-29, thus reinstituting winter time.
918 Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
919 predicted. (Thanks to Dominic Fok.) Adjust future predictions
922 Namibia will switch from +01 with DST to +02 all year on
923 2017-09-03 at 02:00. This affects UT offsets starting 2018-04-01
924 at 02:00. (Thanks to Steffen Thorsen.)
926 Sudan will switch from +03 to +02 on 2017-11-01. (Thanks to Ahmed
927 Atyya and Yahia Abdalla.) South Sudan is not switching, so
928 Africa/Juba is no longer a link to Africa/Khartoum.
930 Tonga has likely ended its experiment with DST, and will not
931 adjust its clocks on 2017-11-05. Although Tonga has not announced
932 whether it will continue to observe DST, the IATA is assuming that
933 it will not. (Thanks to David Wade.)
935 Turks & Caicos will switch from -04 all year to -05 with US DST on
936 2018-03-11 at 03:00. This affects UT offsets starting 2018-11-04
937 at 02:00. (Thanks to Steffen Thorsen.)
939 Changes to past timestamps
941 Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
942 (Thanks to Arthur David Olson.)
944 Detroit did not observe DST in 1967.
946 Use railway time for Asia/Kolkata before 1941, by switching to
947 Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
948 1906. Also, treat 1941-2's +0630 as DST, like 1942-5.
950 Europe/Dublin's 1946 and 1947 fallback transitions occurred at
951 02:00 standard time, not 02:00 DST. (Thanks to Michael Deckers.)
953 Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
954 American time in 1892, not 1879. (Thanks to Michael Deckers.)
956 Adjust the 1867 transition in Alaska to better reflect the
957 historical record, by changing it to occur on 1867-10-18 at 15:30
958 Sitka time rather than at the start of 1867-10-17 local time.
959 Although strictly speaking this is accurate only for Sitka,
960 the rest of Alaska's blanks need to be filled in somehow.
962 Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
963 (Thanks to Michael Deckers.)
965 Add 7 s to the UT offset in Asia/Yangon before 1920.
967 Changes to zone names
969 Remove Canada/East-Saskatchewan from the 'backward' file, as it
970 exceeded the 14-character limit and was an unused misnomer anyway.
972 Changes to build procedure
974 To support applications that prefer to read time zone data in text
975 form, two zic input files tzdata.zi and leapseconds are now
976 installed by default. The commands 'zic tzdata.zi' and 'zic -L
977 leapseconds tzdata.zi' can reproduce the tzdata binary files
978 without and with leap seconds, respectively. To prevent these two
979 new files from being installed, use 'make TZDATA_TEXT=', and to
980 suppress leap seconds from the tzdata text installation, use 'make
981 TZDATA_TEXT=tzdata.zi'.
983 'make BACKWARD=' now suppresses backward-compatibility names
984 like 'US/Pacific' that are defined in the 'backward' and
987 'make check' now works on systems that lack a UTF-8 locale,
988 or that lack the nsgmls program. Set UTF8_LOCALE to configure
989 the name of a UTF-8 locale, if you have one.
991 Y2K runtime checks are no longer enabled by default. Add
992 -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
993 adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
994 to disable them. (New name suggested by Brian Inglis.)
996 The build procedure for zdump now works on AIX 7.1.
997 (Problem reported by Kees Dekker.)
1001 zic and the reference runtime now reject multiple leap seconds
1002 within 28 days of each other, or leap seconds before the Epoch.
1003 As a result, support for double leap seconds, which was
1004 obsolescent and undocumented, has been removed. Double leap
1005 seconds were an error in the C89 standard; they have never existed
1006 in civil timekeeping. (Thanks to Robert Elz and Bradley White for
1007 noticing glitches in the code that uncovered this problem.)
1009 zic now warns about use of the obsolescent and undocumented -y
1010 option, and about use of the obsolescent TYPE field of Rule lines.
1012 zic now allows unambiguous abbreviations like "Sa" and "Su" for
1013 weekdays; formerly it rejected them due to a bug. Conversely, zic
1014 no longer considers non-prefixes to be abbreviations; for example,
1015 it no longer accepts "lF" as an abbreviation for "lastFriday".
1016 Also, zic warns about the undocumented usage with a "last-"
1017 prefix, e.g., "last-Fri".
1019 Similarly, zic now accepts the unambiguous abbreviation "L" for
1020 "Link" in ordinary context and for "Leap" in leap-second context.
1021 Conversely, zic no longer accepts non-prefixes such as "La" as
1022 abbreviations for words like "Leap".
1024 zic no longer accepts leap second lines in ordinary input, or
1025 ordinary lines in leap second input. Formerly, zic sometimes
1026 warned about this undocumented usage and handled it incorrectly.
1028 The new macro HAVE_TZNAME governs whether the tzname external
1029 variable is exported, instead of USG_COMPAT. USG_COMPAT now
1030 governs only the external variables "timezone" and "daylight".
1031 This change is needed because the three variables are not in the
1032 same category: although POSIX requires tzname, it specifies the
1033 other two variables as optional. Also, USG_COMPAT is now 1 or 0:
1034 if not defined, the code attempts to guess it from other macros.
1036 localtime.c and difftime.c no longer require stdio.h, and .c files
1037 other than zic.c no longer require sys/wait.h.
1039 zdump.c no longer assumes snprintf. (Reported by Jonathan Leffler.)
1041 Calculation of time_t extrema works around a bug in GCC 4.8.4
1042 (Reported by Stan Shebs and Joseph Myers.)
1044 zic.c no longer mistranslates formats of line numbers in non-English
1045 locales. (Problem reported by Benno Schulenberg.)
1047 Several minor changes have been made to the code to make it a
1048 bit easier to port to MS-Windows and Solaris. (Thanks to Kees
1049 Dekker for reporting the problems.)
1051 Changes to documentation and commentary
1053 The two new files 'theory.html' and 'calendars' contain the
1054 contents of the removed file 'Theory'. The goal is to document
1055 tzdb theory more accessibly.
1057 The zic man page now documents abbreviation rules.
1059 tz-link.htm now covers how to apply tzdata changes to clients.
1060 (Thanks to Jorge Fábregas for the AIX link.) It also mentions MySQL.
1062 The leap-seconds.list URL has been updated to something that is
1063 more reliable for tzdb. (Thanks to Tim Parenti and Brian Inglis.)
1065 Release 2017b - 2017-03-17 07:30:38 -0700
1067 Briefly: Haiti has resumed DST.
1069 Changes to past and future timestamps
1071 Haiti resumed observance of DST in 2017. (Thanks to Steffen Thorsen.)
1073 Changes to past timestamps
1075 Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
1077 Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
1078 is one byte over the POSIX limit. (Problem reported by Derick Rethans.)
1082 The reference localtime implementation now falls back on the
1083 current US daylight-saving transition rules rather than the
1084 1987-2006 rules. This fallback occurs only when (1) the TZ
1085 environment variable has a value like "AST4ADT" that asks
1086 for daylight saving time but does not specify the rules, (2) there
1087 is no file by that name, and (3) the TZDEFRULES file cannot be
1088 loaded. (Thanks to Tom Lane.)
1091 Release 2017a - 2017-02-28 00:05:36 -0800
1093 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
1096 Changes to future timestamps
1098 Mongolia no longer observes DST. (Thanks to Ganbold Tsagaankhuu.)
1100 Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
1101 Its clocks diverge from America/Santiago starting 2017-05-13 at
1102 23:00, hiving off a new zone America/Punta_Arenas. Although the
1103 Chilean government says this change expires in May 2019, for now
1104 assume it's permanent. (Thanks to Juan Correa and Deborah
1105 Goldsmith.) This also affects Antarctica/Palmer.
1107 Changes to past timestamps
1109 Fix many entries for historical timestamps for Europe/Madrid
1110 before 1979, to agree with tables compiled by Pere Planesas of the
1111 National Astronomical Observatory of Spain. As a side effect,
1112 this changes some timestamps for Africa/Ceuta before 1929, which
1113 are probably guesswork anyway. (Thanks to Steve Allen and
1114 Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
1115 correcting the 1901 transition.)
1117 Ecuador observed DST from 1992-11-28 to 1993-02-05.
1118 (Thanks to Alois Treindl.)
1120 Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
1121 (Thanks to Stepan Golosunov.)
1123 Changes to past and future time zone abbreviations
1125 Switch to numeric time zone abbreviations for South America, as
1126 part of the ongoing project of removing invented abbreviations.
1127 This avoids the need to invent an abbreviation for the new Chilean
1128 new zone. Similarly, switch from invented to numeric time zone
1129 abbreviations for Afghanistan, American Samoa, the Azores,
1130 Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
1131 Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
1132 Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
1133 Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
1134 the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
1135 Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
1136 Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
1137 Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
1138 Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
1139 Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
1140 for half-hour daylight saving time in Belize before 1944 and in
1141 the Dominican Republic before 1975; and for Canary Islands before
1142 1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
1143 Indian Summer Time before 1942, for Indonesia before around 1964,
1144 for Kenya before 1960, for Liberia before 1973, for Madeira before
1145 1967, for Namibia before 1943, for the Netherlands in 1937-9, for
1146 Pakistan before 1971, for Western Sahara before 1977, and for
1147 Zaporozhye in 1880-1924.
1149 For Alaska time from 1900 through 1967, instead of "CAT" use the
1150 abbreviation "AST", the abbreviation commonly used at the time
1151 (Atlantic Standard Time had not been standardized yet). Use "AWT"
1152 and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
1154 Use "CST" and "CDT" instead of invented abbreviations for Macau
1155 before 1999 and Taiwan before 1938, and use "JST" instead of the
1156 invented abbreviation "JCST" for Japan and Korea before 1938.
1158 Change to database entry category
1160 Move the Pacific/Johnston link from 'australasia' to 'backward',
1161 since Johnston is now uninhabited.
1165 zic no longer mishandles some transitions in January 2038 when it
1166 attempts to work around Qt bug 53071. This fixes a bug affecting
1167 Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
1168 now contains a workaround, useful when loading a file generated by
1169 a buggy zic. (Problem and localtime.c fix reported by Bradley
1172 zdump -i now outputs non-hour numeric time zone abbreviations
1173 without a colon, e.g., "+0530" rather than "+05:30". This agrees
1174 with zic %z and with common practice, and simplifies auditing of
1177 zdump is now buildable again with -DUSE_LTZ=0.
1178 (Problem reported by Joseph Myers.)
1180 zdump.c now always includes private.h, to avoid code duplication
1181 with private.h. (Problem reported by Kees Dekker.)
1183 localtime.c no longer mishandles early or late timestamps
1184 when TZ is set to a POSIX-style string that specifies DST.
1185 (Problem reported by Kees Dekker.)
1187 date and strftime now cause %z to generate "-0000" instead of
1188 "+0000" when the UT offset is zero and the time zone abbreviation
1191 Changes to documentation and commentary
1193 The 'Theory' file now better documents choice of historical time
1194 zone abbreviations. (Problems reported by Michael Deckers.)
1196 tz-link.htm now covers leap smearing, which is popular in clouds.
1199 Release 2016j - 2016-11-22 23:17:13 -0800
1201 Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
1203 Changes to future timestamps
1205 Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
1206 This hives off a new zone Europe/Saratov from Europe/Volgograd.
1207 (Thanks to Yuri Konotopov and Stepan Golosunov.)
1209 Changes to past timestamps
1211 The new zone Asia/Atyrau for Atyraū Region, Kazakhstan, is like
1212 Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
1213 1999, not fall 1994. (Thanks to Stepan Golosunov.)
1215 Changes to past time zone abbreviations
1217 Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
1218 summer time before 1948. The old use of "EET" was a typo.
1222 zic no longer mishandles file systems that lack hard links, fixing
1223 bugs introduced in 2016g. (Problems reported by Tom Lane.)
1224 Also, when the destination already contains symbolic links, zic
1225 should now work better on systems where the 'link' system call
1226 does not follow symbolic links.
1228 Changes to documentation and commentary
1230 tz-link.htm now documents the relationship between release version
1231 numbers and development-repository commit tags. (Suggested by
1234 The 'Theory' file now documents UT.
1236 iso3166.tab now accents "Curaçao", and commentary now mentions
1237 the names "Cabo Verde" and "Czechia". (Thanks to Jiří Boháč.)
1240 Release 2016i - 2016-11-01 23:19:52 -0700
1242 Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
1243 reintroduces DST on 2016-11-06.
1245 Changes to future timestamps
1247 Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
1248 2017-01-15 at 03:00. Assume future observances in Tonga will be
1249 from the first Sunday in November through the third Sunday in
1250 January, like Fiji. (Thanks to Pulu ʻAnau.) Switch to numeric
1251 time zone abbreviations for this zone.
1253 Changes to past and future timestamps
1255 Northern Cyprus is now +03 year round, causing a split in Cyprus
1256 time zones starting 2016-10-30 at 04:00. This creates a zone
1257 Asia/Famagusta. (Thanks to Even Scharning and Matt Johnson.)
1259 Antarctica/Casey switched from +08 to +11 on 2016-10-22.
1260 (Thanks to Steffen Thorsen.)
1262 Changes to past timestamps
1264 Several corrections were made for pre-1975 timestamps in Italy.
1265 These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
1268 First, the 1893-11-01 00:00 transition in Italy used the new UT
1269 offset (+01), not the old (+00:49:56). (Thanks to Michael
1272 Second, rules for daylight saving in Italy were changed to agree
1273 with Italy's National Institute of Metrological Research (INRiM)
1274 except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
1275 Inglis, and Michael Deckers):
1277 The 1916-06-03 transition was at 24:00, not 00:00.
1279 The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
1282 The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
1285 The 1944-09-17 transition was at 03:00, not 01:00. This
1286 particular change is taken from Italian law as INRiM's table,
1287 (which says 02:00) appears to have a typo here. Also, keep the
1288 1944-04-03 transition for Europe/Rome, as Rome was controlled by
1291 The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
1296 The code should now be buildable on AmigaOS merely by setting the
1297 appropriate Makefile variables. (From a patch by Carsten Larsen.)
1300 Release 2016h - 2016-10-19 23:17:57 -0700
1302 Changes to future timestamps
1304 Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
1305 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that
1306 future fall transitions will be on the last Saturday of October
1307 at 01:00, which is consistent with predicted spring transitions
1308 on the last Saturday of March. (Thanks to Tim Parenti.)
1310 Changes to past timestamps
1312 In Turkey, transitions in 1986-1990 were at 01:00 standard time
1313 not at 02:00, and the spring 1994 transition was on March 20, not
1314 March 27. (Thanks to Kıvanç Yazan.)
1316 Changes to past and future time zone abbreviations
1318 Asia/Colombo now uses numeric time zone abbreviations like "+0530"
1319 instead of alphabetic ones like "IST" and "LKT". Various
1320 English-language sources use "IST", "LKT" and "SLST", with no
1321 working consensus. (Usage of "SLST" mentioned by Sadika
1326 zic no longer mishandles relativizing file names when creating
1327 symbolic links like /etc/localtime, when these symbolic links
1328 are outside the usual directory hierarchy. This fixes a bug
1329 introduced in 2016g. (Problem reported by Andreas Stieger.)
1331 Changes to build procedure
1333 New rules 'traditional_tarballs' and 'traditional_signatures' for
1334 building just the traditional-format distribution. (Requested by
1337 The file 'version' is now put into the tzdata tarball too.
1338 (Requested by Howard Hinnant.)
1340 Changes to documentation and commentary
1342 The 'Theory' file now has a section on interface stability.
1343 (Requested by Paul Koning.) It also mentions features like
1344 tm_zone and localtime_rz that have long been supported by the
1347 tz-link.htm has improved coverage of time zone boundaries suitable
1348 for geolocation. (Thanks to heads-ups from Evan Siroky and Matt
1351 The US commentary now mentions Allen and the "day of two noons".
1353 The Fiji commentary mentions the government's 2016-10-03 press
1354 release. (Thanks to Raymond Kumar.)
1357 Release 2016g - 2016-09-13 08:56:38 -0700
1359 Changes to future timestamps
1361 Turkey switched from EET/EEST (+02/+03) to permanent +03,
1362 effective 2016-09-07. (Thanks to Burak AYDIN.) Use "+03" rather
1363 than an invented abbreviation for the new time.
1365 New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
1366 (Thanks to Tim Parenti.)
1368 Changes to past timestamps
1370 For America/Los_Angeles, spring-forward transition times have been
1371 corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
1374 For zones using Soviet time on 1919-07-01, transitions to UT-based
1375 time were at 00:00 UT, not at 02:00 local time. The affected
1376 zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
1377 Europe/Ulyanovsk. (Thanks to Alexander Belopolsky.)
1379 Changes to past and future time zone abbreviations
1381 The Factory zone now uses the time zone abbreviation -00 instead
1382 of a long English-language string, as -00 is now the normal way to
1383 represent an undefined time zone.
1385 Several zones in Antarctica and the former Soviet Union, along
1386 with zones intended for ships at sea that cannot use POSIX TZ
1387 strings, now use numeric time zone abbreviations instead of
1388 invented or obsolete alphanumeric abbreviations. The affected
1389 zones are Antarctica/Casey, Antarctica/Davis,
1390 Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
1391 Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
1392 Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
1393 Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
1394 Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
1395 Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
1396 Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
1397 Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
1398 Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
1399 Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
1400 Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
1401 Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
1402 Europe/Minsk, Europe/Samara, Europe/Volgograd, and
1403 Indian/Kerguelen. For Europe/Moscow the invented abbreviation MSM
1404 was replaced by +05, whereas MSK and MSD were kept as they are not
1405 our invention and are widely used.
1407 Changes to zone names
1409 Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
1410 (Thanks to David Massoud.)
1414 zic no longer generates binary files containing POSIX TZ-like
1415 strings that disagree with the local time type after the last
1416 explicit transition in the data. This fixes a bug with
1417 Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
1418 on the reference platform. (Thanks to Alexander Belopolsky for
1419 reporting the bug and suggesting a way forward.)
1421 If the installed localtime and/or posixrules files are symbolic
1422 links, zic now keeps them symbolic links when updating them, for
1423 compatibility with platforms like OpenSUSE where other programs
1424 configure these files as symlinks.
1426 zic now avoids hard linking to symbolic links, avoids some
1427 unnecessary mkdir and stat system calls, and uses shorter file
1430 zdump has a new -i option to generate transitions in a
1431 more-compact but still human-readable format. This option is
1432 experimental, and the output format may change in future versions.
1433 (Thanks to Jon Skeet for suggesting that an option was needed,
1434 and thanks to Tim Parenti and Chris Rovick for further comments.)
1436 Changes to build procedure
1438 An experimental distribution format is available, in addition
1439 to the traditional format which will continue to be distributed.
1440 The new format is a tarball tzdb-VERSION.tar.lz with signature
1441 file tzdb-VERSION.tar.lz.asc. It unpacks to a top-level directory
1442 tzdb-VERSION containing the code and data of the traditional
1443 two-tarball format, along with extra data that may be useful.
1444 (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
1445 for comments about the experimental format.)
1447 The release version number is now more accurate in the usual case
1448 where releases are built from a Git repository. For example, if
1449 23 commits and some working-file changes have been made since
1450 release 2016g, the version number is now something like
1451 '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
1452 Tagged releases use the same version number format as before,
1453 e.g., '2016g'. To support the more-accurate version number, its
1454 specification has moved from a line in the Makefile to a new
1455 source file 'version'.
1457 The experimental distribution contains a file to2050.tzs that
1458 contains what should be the output of 'zdump -i -c 2050' on
1459 primary zones. If this file is available, 'make check' now checks
1460 that zdump generates this output.
1462 'make check_web' now works on Fedora-like distributions.
1464 Changes to documentation and commentary
1466 tzfile.5 now documents the new restriction on POSIX TZ-like
1467 strings that is now implemented by zic.
1469 Comments now cite URLs for some 1917-1921 Russian DST decrees.
1470 (Thanks to Alexander Belopolsky.)
1472 tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
1473 (thanks to Meno Hochschild) and ThreeTen-Extra, and its
1474 description of Java 8 has been brought up to date (thanks to
1475 Stephen Colebourne). Its description of local time on Mars has
1476 been updated to match current practice, and URLs have been updated
1477 and some obsolete ones removed.
1480 Release 2016f - 2016-07-05 16:26:51 +0200
1482 Changes affecting future timestamps
1484 The Egyptian government changed its mind on short notice, and
1485 Africa/Cairo will not introduce DST starting 2016-07-07 after all.
1486 (Thanks to Mina Samuel.)
1488 Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
1489 (Thanks to Stepan Golosunov.)
1491 Changes to past and future timestamps
1493 Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
1494 abbreviations instead of invented ones.
1496 Changes affecting past timestamps
1498 Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
1499 (Thanks to Stepan Golosunov.)
1502 Release 2016e - 2016-06-14 08:46:16 -0700
1504 Changes affecting future timestamps
1506 Africa/Cairo observes DST in 2016 from July 7 to the end of October.
1507 Guess October 27 and 24:00 transitions. (Thanks to Steffen Thorsen.)
1508 For future years, guess April's last Thursday to October's last
1509 Thursday except for Ramadan.
1511 Changes affecting past timestamps
1513 Locations while uninhabited now use '-00', not 'zzz', as a
1514 placeholder time zone abbreviation. This is inspired by Internet
1515 RFC 3339 and is more consistent with numeric time zone
1516 abbreviations already used elsewhere. The change affects several
1517 arctic and antarctic locations, e.g., America/Cambridge_Bay before
1518 1920 and Antarctica/Troll before 2005.
1520 Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
1521 at 03:00, not 23:00 the previous day. (Thanks to Michael Deckers.)
1525 zic now outputs a dummy transition at time 2**31 - 1 in zones
1526 whose POSIX-style TZ strings contain a '<'. This mostly works
1527 around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
1528 (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
1530 Changes affecting documentation and commentary
1532 tz-link.htm says why governments should give plenty of notice for
1533 time zone or DST changes, and refers to Matt Johnson's blog post.
1535 tz-link.htm mentions Tzdata for Elixir. (Thanks to Matt Johnson.)
1538 Release 2016d - 2016-04-17 22:50:29 -0700
1540 Changes affecting future timestamps
1542 America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
1543 (Thanks to Alexander Krivenyshev for the heads-up.)
1545 Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
1546 (Thanks to Alexander Krivenyshev and Matt Johnson.)
1548 New zone Asia/Tomsk, split off from Asia/Novosibirsk. It covers
1549 Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
1550 at 02:00. (Thanks to Stepan Golosunov.)
1552 Changes affecting past timestamps
1554 New zone Europe/Kirov, split off from Europe/Volgograd. It covers
1555 Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
1556 1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
1557 the same change. (Thanks to Stepan Golosunov.)
1559 Russia and nearby locations had daylight-saving transitions on
1560 1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
1561 1992-03-28 at 23:00 and 1992-09-26 at 23:00. (Thanks to Stepan
1564 Many corrections to historical time in Kazakhstan from 1991
1565 through 2005. (Thanks to Stepan Golosunov.) Replace Kazakhstan's
1566 invented time zone abbreviations with numeric abbreviations.
1568 Changes to commentary
1570 Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
1573 Release 2016c - 2016-03-23 00:51:27 -0700
1575 Changes affecting future timestamps
1577 Azerbaijan no longer observes DST. (Thanks to Steffen Thorsen.)
1579 Chile reverts from permanent to seasonal DST. (Thanks to Juan
1580 Correa for the heads-up, and to Tim Parenti for corrections.)
1581 Guess that future transitions are August's and May's second
1582 Saturdays at 24:00 mainland time. Also, call the period from
1583 2014-09-07 through 2016-05-14 daylight saving time instead of
1584 standard time, as that seems more appropriate now.
1586 Changes affecting past timestamps
1588 Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
1589 +02/+03 on 1989-03-26, not 1991-03-31. Europe/Volgograd changed
1590 from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
1591 (Thanks to Stepan Golosunov.)
1593 Changes to commentary
1595 Several updates and URLs for historical and proposed Russian changes.
1596 (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
1599 Release 2016b - 2016-03-12 17:30:14 -0800
1603 Starting with release 2016b, some data entries cause zic implementations
1604 derived from tz releases 2005j through 2015e to issue warnings like
1605 "time zone abbreviation differs from POSIX standard (+03)".
1606 These warnings should not otherwise affect zic's output and can safely be
1607 ignored on today's platforms, as the warnings refer to a restriction in
1608 POSIX.1-1988 that was removed in POSIX.1-2001. One way to suppress the
1609 warnings is to upgrade to zic derived from tz releases 2015f and later.
1611 Changes affecting future timestamps
1613 New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
1614 Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
1615 2016-03-27 at 02:00 local time. They need distinct zones since their
1616 post-1970 histories disagree. New zone Asia/Barnaul for Altai Krai and
1617 Altai Republic, Russia, which will switch from +06 to +07 on the same date
1618 and local time. The Astrakhan change is already official; the others have
1619 passed the first reading in the State Duma and are extremely likely.
1620 Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
1621 (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
1622 and Stepan Golosunov for followup.)
1624 As a trial of a new system that needs less information to be made up,
1625 the new zones use numeric time zone abbreviations like "+04"
1626 instead of invented abbreviations like "ASTT".
1628 Haiti will not observe DST in 2016. (Thanks to Jean Antoine via
1631 Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
1632 (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
1633 Saturday at 01:00, not March's last Friday at 24:00.
1635 Changes affecting past timestamps
1637 Europe/Chisinau observed DST during 1990, and switched from +04 to
1638 +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
1639 (Thanks to Stepan Golosunov.)
1641 1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
1642 KUYT/KUYST. (Thanks to Stepan Golosunov.)
1646 tzselect's diagnostics and checking, and checktab.awk's checking,
1647 have been improved. (Thanks to J William Piggott.)
1649 tzcode now builds under MinGW. (Thanks to Ian Abbott and Esben Haabendal.)
1651 tzselect now tests Julian-date TZ settings more accurately.
1652 (Thanks to J William Piggott.)
1654 Changes to commentary
1656 Comments in zone tables have been improved. (Thanks to J William Piggott.)
1658 tzselect again limits its menu comments so that menus fit on a
1659 24×80 alphanumeric display.
1661 A new web page tz-how-to.html. (Thanks to Bill Seymour.)
1663 In the Theory file, the description of possible time zone abbreviations in
1664 tzdata has been cleaned up, as the old description was unclear and
1665 inconsistent. (Thanks to Alain Mouette for reporting the problem.)
1668 Release 2016a - 2016-01-26 23:28:02 -0800
1670 Changes affecting future timestamps
1672 America/Cayman will not observe daylight saving this year after all.
1673 Revert our guess that it would. (Thanks to Matt Johnson.)
1675 Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
1676 (Thanks to Alexander Krivenyshev.)
1678 Asia/Tehran now has DST predictions for the year 2038 and later,
1679 to be March 21 00:00 to September 21 00:00. This is likely better
1680 than predicting no DST, albeit off by a day every now and then.
1682 Changes affecting past and future timestamps
1684 America/Metlakatla switched from PST all year to AKST/AKDT on
1685 2015-11-01 at 02:00. (Thanks to Steffen Thorsen.)
1687 America/Santa_Isabel has been removed, and replaced with a
1688 backward compatibility link to America/Tijuana. Its contents were
1689 apparently based on a misreading of Mexican legislation.
1691 Changes affecting past timestamps
1693 Asia/Karachi's two transition times in 2002 were off by a minute.
1694 (Thanks to Matt Johnson.)
1696 Changes affecting build procedure
1698 An installer can now combine leap seconds with use of the backzone file,
1699 e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
1700 The old 'make posix_packrat' rule is now marked as obsolescent.
1701 (Thanks to Ian Abbott for an initial implementation.)
1703 Changes affecting documentation and commentary
1705 A new file LICENSE makes it easier to see that the code and data
1706 are mostly public-domain. (Thanks to James Knight.) The three
1707 non-public-domain files now use the current (3-clause) BSD license
1708 instead of older versions of that license.
1710 tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
1711 CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
1712 on editing tz source files (with a mention of Sublime zoneinfo,
1713 thanks to Gilmore Davidson).
1715 The Theory and asia files now mention the 2015 book "The Global
1716 Transformation of Time, 1870-1950", and cite a couple of reviews.
1718 The America/Chicago entry now documents the informal use of US
1719 central time in Fort Pierre, South Dakota. (Thanks to Rick
1720 McDermid, Matt Johnson, and Steve Jones.)
1723 Release 2015g - 2015-10-01 00:39:51 -0700
1725 Changes affecting future timestamps
1727 Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
1730 Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
1731 (Thanks to Alexander Krivenyshev.)
1733 Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
1734 (Thanks to Ken Rylander.)
1736 Fort Nelson, British Columbia will not fall back on 2015-11-01. It has
1737 effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
1738 New zone America/Fort_Nelson. (Thanks to Matt Johnson.)
1740 Changes affecting past timestamps
1742 Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
1744 Changes affecting code
1746 localtime no longer mishandles America/Anchorage after 2037.
1747 (Thanks to Bradley White for reporting the bug.)
1749 On hosts with signed 32-bit time_t, localtime no longer mishandles
1750 Pacific/Fiji after 2038-01-16 14:00 UTC.
1752 The localtime module allows the variables 'timezone', 'daylight',
1753 and 'altzone' to be in common storage shared with other modules,
1754 and declares them in case the system <time.h> does not.
1755 (Problems reported by Kees Dekker.)
1757 On platforms with tm_zone, strftime.c now assumes it is not NULL.
1758 This simplifies the code and is consistent with zdump.c.
1759 (Problem reported by Christos Zoulas.)
1761 Changes affecting documentation
1763 The tzfile man page now documents that transition times denote the
1764 starts (not the ends) of the corresponding time periods.
1765 (Ambiguity reported by Bill Seymour.)
1768 Release 2015f - 2015-08-10 18:06:56 -0700
1770 Changes affecting future timestamps
1772 North Korea switches to +0830 on 2015-08-15. (Thanks to Steffen Thorsen.)
1773 The abbreviation remains "KST". (Thanks to Robert Elz.)
1775 Uruguay no longer observes DST. (Thanks to Steffen Thorsen
1778 Changes affecting past and future timestamps
1780 Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
1781 (Thanks to Roman Tudos.)
1783 Changes affecting data format and code
1785 zic's '-y YEARISTYPE' option is no longer documented. The TYPE
1786 field of a Rule line should now be '-'; the old values 'even',
1787 'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
1788 Although the implementation has not changed, these features do not
1789 work in the default installation, they are not used in the data,
1790 and they are now considered obsolescent.
1792 zic now checks that two rules don't take effect at the same time.
1793 (Thanks to Jon Skeet and Arthur David Olson.) Constraints on
1794 simultaneity are now documented.
1796 The two characters '%z' in a zone format now stand for the UT
1797 offset, e.g., '-07' for seven hours behind UT and '+0530' for
1798 five hours and thirty minutes ahead. This better supports time
1799 zone abbreviations conforming to POSIX.1-2001 and later.
1801 Changes affecting installed data files
1803 Comments for America/Halifax and America/Glace_Bay have been improved.
1804 (Thanks to Brian Inglis.)
1806 Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
1807 Europe/Sofia, and Europe/Tallinn. This yields slightly smaller
1808 installed data files for Europe/Simferopol and Europe/Tallinn.
1809 It does not affect timestamps. (Thanks to Howard Hinnant.)
1811 Changes affecting code
1813 zdump and zic no longer warn about valid time zone abbreviations
1816 Some Visual Studio 2013 warnings have been suppressed.
1817 (Thanks to Kees Dekker.)
1819 'date' no longer sets the time of day and its -a, -d, -n and -t
1820 options have been removed. Long obsolescent, the implementation
1821 of these features had porting problems. Builders no longer need
1822 to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
1823 (Thanks to Kees Dekker for pointing out the problem.)
1825 Changes affecting documentation
1827 The Theory file mentions naming issues earlier, as these seem to be
1828 poorly publicized (thanks to Gilmore Davidson for reporting the problem).
1830 tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
1832 Mention that Herbert Samuel introduced the term "Summer Time".
1835 Release 2015e - 2015-06-13 10:56:02 -0700
1837 Changes affecting future timestamps
1839 Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
1840 not 06-13 and 07-18 as we had guessed. (Thanks to Milamber.)
1842 Assume Cayman Islands will observe DST starting next year, using US rules.
1843 Although it isn't guaranteed, it is the most likely.
1845 Changes affecting data format
1847 The file 'iso3166.tab' now uses UTF-8, so that its entries can better
1848 spell the names of Åland Islands, Côte d'Ivoire, and Réunion.
1850 Changes affecting code
1852 When displaying data, tzselect converts it to the current locale's
1853 encoding if the iconv command works. (Problem reported by random832.)
1855 tzselect no longer mishandles Dominica, fixing a bug introduced
1856 in Release 2014f. (Problem reported by Owen Leibman.)
1858 zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
1859 This fixes a bug introduced in Release 2014f.
1860 (Problem reported by Leonardo Chiquitto.)
1863 Release 2015d - 2015-04-24 08:09:46 -0700
1865 Changes affecting future timestamps
1867 Egypt will not observe DST in 2015 and will consider canceling it
1868 permanently. For now, assume no DST indefinitely.
1869 (Thanks to Ahmed Nazmy and Tim Parenti.)
1871 Changes affecting past timestamps
1873 America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
1874 1966-07-01. Also, Yukon's time zone history is documented better.
1875 (Thanks to Brian Inglis and Dennis Ferguson.)
1877 Change affecting past and future time zone abbreviations
1879 The abbreviations for Hawaii-Aleutian standard and daylight times
1880 have been changed from HAST/HADT to HST/HDT, as per US Government
1881 Printing Office style. This affects only America/Adak since 1983,
1882 as America/Honolulu was already using the new style.
1884 Changes affecting code
1886 zic has some minor performance improvements.
1889 Release 2015c - 2015-04-11 08:55:55 -0700
1891 Changes affecting future timestamps
1893 Egypt's spring-forward transition is at 24:00 on April's last Thursday,
1894 not 00:00 on April's last Friday. 2015's transition will therefore be on
1895 Thursday, April 30 at 24:00, not Friday, April 24 at 00:00. Similar fixes
1896 apply to 2026, 2037, 2043, etc. (Thanks to Steffen Thorsen.)
1898 Changes affecting past timestamps
1900 The following changes affect some pre-1991 Chile-related timestamps
1901 in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
1903 The 1910 transition was January 10, not January 1.
1905 The 1918 transition was September 10, not September 1.
1907 The UT -04 time observed from 1932 to 1942 is now considered to
1908 be standard time, not year-round DST.
1910 Santiago observed DST (UT -03) from 1946-07-15 through
1911 1946-08-31, then reverted to standard time, then switched to -05
1914 Assume transitions before 1968 were at 00:00, since we have no data
1917 The spring 1988 transition was 1988-10-09, not 1988-10-02.
1918 The fall 1990 transition was 1990-03-11, not 1990-03-18.
1920 Assume no UT offset change for Pacific/Easter on 1890-01-01,
1921 and omit all transitions on Pacific/Easter from 1942 through 1946
1922 since we have no data suggesting that they existed.
1924 One more zone has been turned into a link, as it differed
1925 from an existing zone only for older timestamps. As usual,
1926 this change affects UT offsets in pre-1970 timestamps only.
1927 The zone's old contents have been moved to the 'backzone' file.
1928 The affected zone is America/Montreal.
1930 Changes affecting commentary
1932 Mention the TZUpdater tool.
1934 Mention "The Time Now". (Thanks to Brandon Ramsey.)
1937 Release 2015b - 2015-03-19 23:28:11 -0700
1939 Changes affecting future timestamps
1941 Mongolia will start observing DST again this year, from the last
1942 Saturday in March at 02:00 to the last Saturday in September at 00:00.
1943 (Thanks to Ganbold Tsagaankhuu.)
1945 Palestine will start DST on March 28, not March 27. Also,
1946 correct the fall 2014 transition from September 26 to October 24.
1947 Adjust future predictions accordingly. (Thanks to Steffen Thorsen.)
1949 Changes affecting past timestamps
1951 The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
1952 regression. (Thanks to Stuart Bishop for reporting the problem.)
1954 Some more zones have been turned into links, when they differed
1955 from existing zones only for older timestamps. As usual,
1956 these changes affect UT offsets in pre-1970 timestamps only.
1957 Their old contents have been moved to the 'backzone' file.
1958 The affected zones are: America/Antigua, America/Cayman,
1959 Pacific/Midway, and Pacific/Saipan.
1961 Changes affecting time zone abbreviations
1963 Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
1966 Changes affecting code
1968 Fix integer overflow bug in reference 'mktime' implementation.
1969 (Problem reported by Jörg Richter.)
1971 Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
1972 to be used in the same executable as standard-library time_t functions.
1973 (Problems reported by Bradley White.)
1975 Changes affecting commentary
1977 Cite the recent Mexican decree changing Quintana Roo's time zone.
1978 (Thanks to Carlos Raúl Perasso.)
1980 Likewise for the recent Chilean decree. (Thanks to Eduardo Romero Urra.)
1982 Update info about Mars time.
1985 Release 2015a - 2015-01-29 22:35:20 -0800
1987 Changes affecting future timestamps
1989 The Mexican state of Quintana Roo, represented by America/Cancun,
1990 will shift from Central Time with DST to Eastern Time without DST
1991 on 2015-02-01 at 02:00. (Thanks to Steffen Thorsen and Gwillim Law.)
1993 Chile will not change clocks in April or thereafter; its new standard time
1994 will be its old daylight saving time. This affects America/Santiago,
1995 Pacific/Easter, and Antarctica/Palmer. (Thanks to Juan Correa.)
1997 New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
1998 (Thanks to Tim Parenti.)
2000 Changes affecting past timestamps
2002 Iceland observed DST in 1919 and 1921, and its 1939 fallback
2003 transition was Oct. 29, not Nov. 29. Remove incorrect data from
2004 Shanks about time in Iceland between 1837 and 1908.
2006 Some more zones have been turned into links, when they differed
2007 from existing zones only for older timestamps. As usual,
2008 these changes affect UT offsets in pre-1970 timestamps only.
2009 Their old contents have been moved to the 'backzone' file.
2010 The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
2013 Changes affecting code
2015 tzalloc now scrubs time zone abbreviations compatibly with the way
2016 that tzset always has, by replacing invalid bytes with '_' and by
2017 shortening too-long abbreviations.
2019 tzselect ports to POSIX awk implementations, no longer mishandles
2020 POSIX TZ settings when GNU awk is used, and reports POSIX TZ
2021 settings to the user. (Thanks to Stefan Kuhn.)
2023 Changes affecting build procedure
2025 'make check' now checks for links to links in the data.
2026 One such link (for Africa/Asmera) has been fixed.
2027 (Thanks to Stephen Colebourne for pointing out the problem.)
2029 Changes affecting commentary
2031 The leapseconds file commentary now mentions the expiration date.
2032 (Problem reported by Martin Burnicki.)
2034 Update Mexican Library of Congress URL.
2037 Release 2014j - 2014-11-10 17:37:11 -0800
2039 Changes affecting current and future timestamps
2041 Turks & Caicos' switch from US eastern time to UT -04 year-round
2042 did not occur on 2014-11-02 at 02:00. It's currently scheduled
2043 for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
2045 Changes affecting past timestamps
2047 Many pre-1989 timestamps have been corrected for Asia/Seoul and
2048 Asia/Pyongyang, based on sources for the Korean-language Wikipedia
2049 entry for time in Korea. (Thanks to Sanghyuk Jung.) Also, no
2050 longer guess that Pyongyang mimicked Seoul time after World War II,
2051 as this is politically implausible.
2053 Some more zones have been turned into links, when they differed
2054 from existing zones only for older timestamps. As usual,
2055 these changes affect UT offsets in pre-1970 timestamps only.
2056 Their old contents have been moved to the 'backzone' file.
2057 The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
2058 Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
2059 Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
2062 Changes affecting commentary
2064 The commentary is less enthusiastic about Shanks as a source,
2065 and is more careful to distinguish UT from UTC.
2068 Release 2014i - 2014-10-21 22:04:57 -0700
2070 Changes affecting future timestamps
2072 Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
2073 (Thanks to Ken Rylander for the heads-up.) Guess that future
2074 years will use a similar pattern.
2076 A new Zone Pacific/Bougainville, for the part of Papua New Guinea
2077 that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
2078 (Thanks to Kiley Walbom for the heads-up.)
2080 Changes affecting time zone abbreviations
2082 Since Belarus is not changing its clocks even though Moscow is,
2083 the time zone abbreviation in Europe/Minsk is changing from FET
2084 to its more-traditional value MSK on 2014-10-26 at 01:00.
2085 (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
2087 The new abbreviation IDT stands for the pre-1976 use of UT +08 in
2088 Indochina, to distinguish it better from ICT (+07).
2090 Changes affecting past timestamps
2092 Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
2093 (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
2094 authoritative book). Asia/Ho_Chi_Minh has been added to
2095 zone1970.tab, to give tzselect users in Vietnam two choices,
2096 since north and south Vietnam disagreed after our 1970 cutoff.
2098 Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
2099 they differed from existing zones only for older timestamps. As
2100 usual, these changes affect pre-1970 timestamps only. Their old
2101 contents have been moved to the 'backzone' file.
2103 Changes affecting code
2105 The time-related library functions now set errno on failure, and
2106 some crashes in the new tzalloc-related library functions have
2107 been fixed. (Thanks to Christos Zoulas for reporting most of
2108 these problems and for suggesting fixes.)
2110 If USG_COMPAT is defined and the requested timestamp is standard time,
2111 the tz library's localtime and mktime functions now set the extern
2112 variable timezone to a value appropriate for that timestamp; and
2113 similarly for ALTZONE, daylight saving time, and the altzone variable.
2114 This change is a companion to the tzname change in 2014h, and is
2115 designed to make timezone and altzone more compatible with tzname.
2117 The tz library's functions now set errno to EOVERFLOW if they fail
2118 because the result cannot be represented. ctime and ctime_r now
2119 return NULL and set errno when a timestamp is out of range, rather
2120 than having undefined behavior.
2122 Some bugs associated with the new 2014g functions have been fixed.
2123 This includes a bug that largely incapacitated the new functions
2124 time2posix_z and posix2time_z. (Thanks to Christos Zoulas.)
2125 It also includes some uses of uninitialized variables after tzalloc.
2126 The new code uses the standard type 'ssize_t', which the Makefile
2127 now gives porting advice about.
2129 Changes affecting commentary
2131 Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
2134 Release 2014h - 2014-09-25 18:59:03 -0700
2136 Changes affecting past timestamps
2138 America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
2140 Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
2141 not 1920-01-06. The old entry was based on a misinterpretation of Shanks.
2143 Some more zones have been turned into links, when they differed
2144 from existing zones only for older timestamps. As usual,
2145 these changes affect UT offsets in pre-1970 timestamps only.
2146 Their old contents have been moved to the 'backzone' file.
2147 The affected zones are: Africa/Blantyre, Africa/Bujumbura,
2148 Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
2149 Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
2151 Changes affecting code
2153 zdump -V and -v now output gmtoff= values on all platforms,
2154 not merely on platforms defining TM_GMTOFF.
2156 The tz library's localtime and mktime functions now set tzname to a value
2157 appropriate for the requested timestamp, and zdump now uses this
2158 on platforms not defining TM_ZONE, fixing a 2014g regression.
2159 (Thanks to Tim Parenti for reporting the problem.)
2161 The tz library no longer sets tzname if localtime or mktime fails.
2163 zdump -c no longer mishandles transitions near year boundaries.
2164 (Thanks to Tim Parenti for reporting the problem.)
2166 An access to uninitialized data has been fixed.
2167 (Thanks to Jörg Richter for reporting the problem.)
2169 When THREAD_SAFE is defined, the code ports to the C11 memory model.
2170 A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
2171 and two threads race to initialize data used by gmtime-like functions.
2172 (Thanks to Andy Heninger for reporting the problems.)
2174 Changes affecting build procedure
2176 'make check' now checks better for properly-sorted data.
2178 Changes affecting documentation and commentary
2180 zdump's gmtoff=N output is now documented, and its isdst=D output
2181 is now documented to possibly output D values other than 0 or 1.
2183 zdump -c's treatment of years is now documented to use the
2184 Gregorian calendar and Universal Time without leap seconds,
2185 and its behavior at cutoff boundaries is now documented better.
2186 (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
2188 Programs are now documented to use the proleptic Gregorian calendar.
2189 (Thanks to Alan Barrett for the suggestion.)
2191 Fractional-second GMT offsets have been documented for civil time
2192 in 19th-century Chennai, Jakarta, and New York.
2195 Release 2014g - 2014-08-28 12:31:23 -0700
2197 Changes affecting future timestamps
2199 Turks & Caicos is switching from US eastern time to UT -04
2200 year-round, modeled as a switch on 2014-11-02 at 02:00.
2201 [As noted in 2014j, this switch was later delayed.]
2203 Changes affecting past timestamps
2205 Time in Russia or the USSR before 1926 or so has been corrected by
2206 a few seconds in the following zones: Asia/Irkutsk,
2207 Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
2208 Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara. For
2209 Asia/Yekaterinburg the correction is a few minutes. (Thanks to
2210 Vladimir Karpinsky.)
2212 The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
2213 This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
2214 Atlantic/Azores, and Atlantic/Madeira. Also, Lisbon's pre-1912
2215 GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
2216 (Thanks to Stephen Colebourne for pointing to the decree.)
2218 Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
2220 A new file 'backzone' contains data which may appeal to
2221 connoisseurs of old timestamps, although it is out of scope for
2222 the tz database, is often poorly sourced, and contains some data
2223 that is known to be incorrect. The new file is not recommended
2224 for ordinary use and its entries are not installed by default.
2225 (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
2226 Isle of Man entries.)
2228 Some more zones have been turned into links, when they differed
2229 from existing zones only for older timestamps. As usual,
2230 these changes affect UT offsets in pre-1970 timestamps only.
2231 Their old contents have been moved to the 'backzone' file.
2232 The affected zones are: Africa/Bangui, Africa/Brazzaville,
2233 Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
2234 Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
2236 Changes affecting code
2238 Unless NETBSD_INSPIRED is defined to 0, the tz library now
2239 supplies functions for creating and using objects that represent
2240 timezones. The new functions are tzalloc, tzfree, localtime_rz,
2241 mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
2242 time2posix_z. They are intended for performance: for example,
2243 localtime_rz (unlike localtime_r) is trivially thread-safe without
2244 locking. (Thanks to Christos Zoulas for proposing NetBSD-inspired
2245 functions, and to Alan Barrett and Jonathan Lennox for helping to
2248 zdump now builds with the tz library unless USE_LTZ is defined to 0,
2249 This lets zdump use tz features even if the system library lacks them.
2250 To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
2251 TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
2253 zdump now uses localtime_rz if available, as it's significantly faster,
2254 and it can help zdump better diagnose invalid timezone names.
2255 Define HAVE_LOCALTIME_RZ to 0 to suppress this. HAVE_LOCALTIME_RZ
2256 defaults to 1 if NETBSD_INSPIRED && USE_LTZ. When localtime_rz is
2257 not available, zdump now uses localtime_r and tzset if available,
2258 as this is a bit cleaner and faster than plain localtime. Compile
2259 with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
2260 lacks these two functions.
2262 If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
2263 Although not needed for tz's own applications, which are single-threaded,
2264 this supports POSIX better if the tz library is used in multithreaded apps.
2266 Some crashes have been fixed when zdump or the tz library is given
2267 invalid or outlandish input.
2269 The tz library no longer mishandles leap seconds on platforms with
2270 unsigned time_t in timezones that lack ordinary transitions after 1970.
2272 The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
2273 already defined, to make it easier to configure on common platforms.
2274 Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
2276 Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
2277 assumes that reading uninitialized memory yields garbage values
2278 but does not cause other problems such as traps.
2280 If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
2281 more likely to guess right for ambiguous timestamps near
2282 transitions where tm_isdst does not change.
2284 If HAVE_STRFTIME_L is defined to 1, the tz library now defines
2285 strftime_l for compatibility with recent versions of POSIX.
2286 Only the C locale is supported, though. HAVE_STRFTIME_L defaults
2287 to 1 on recent POSIX versions, and to 0 otherwise.
2289 tzselect -c now uses a hybrid distance measure that works better
2290 in Africa. (Thanks to Alan Barrett for noting the problem.)
2292 The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
2293 or when time_tz is defined.
2295 When HAVE_UTMPX_H is set the 'date' command now builds on systems
2296 whose <utmpx.h> file does not define WTMPX_FILE, and when setting
2297 the date it updates the wtmpx file if _PATH_WTMPX is defined.
2298 This affects GNU/Linux and similar systems.
2300 For easier maintenance later, some C code has been simplified,
2301 some lint has been removed, and the code has been tweaked so that
2302 plain 'make' is more likely to work.
2304 The C type 'bool' is now used for boolean values, instead of 'int'.
2306 The long-obsolete LOCALE_HOME code has been removed.
2308 The long-obsolete 'gtime' function has been removed.
2310 Changes affecting build procedure
2312 'zdump' no longer links in ialloc.o, as it's not needed.
2314 'make check_time_t_alternatives' no longer assumes GNU diff.
2316 Changes affecting distribution tarballs
2318 The files checktab.awk and zoneinfo2tdf.pl are now distributed in
2319 the tzdata tarball instead of the tzcode tarball, since they help
2320 maintain the data. The NEWS and Theory files are now also
2321 distributed in the tzdata tarball, as they're relevant for data.
2322 (Thanks to Alan Barrett for pointing this out.) Also, the
2323 leapseconds.awk file is no longer distributed in the tzcode
2324 tarball, since it belongs in the tzdata tarball (where 2014f
2325 inadvertently also distributed it).
2327 Changes affecting documentation and commentary
2329 A new file CONTRIBUTING is distributed. (Thanks to Tim Parenti for
2330 suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
2333 The man pages have been updated to use function prototypes,
2334 to document thread-safe variants like localtime_r, and to document
2335 the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
2338 The fields in Link lines have been renamed to be more descriptive
2339 and more like the parameters of 'ln'. LINK-FROM has become TARGET,
2340 and LINK-TO has become LINK-NAME.
2342 tz-link.htm mentions the IETF's tzdist working group; Windows
2343 Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
2345 Some broken URLs have been fixed in the commentary. (Thanks to
2348 Commentary about Philippines DST has been updated, and commentary
2349 on pre-1970 time in India has been added.
2352 Release 2014f - 2014-08-05 17:42:36 -0700
2354 Changes affecting future timestamps
2356 Russia will subtract an hour from most of its time zones on 2014-10-26
2357 at 02:00 local time. (Thanks to Alexander Krivenyshev.)
2358 There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
2359 Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
2360 (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
2361 (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
2362 (Europe/Samara) are not changing their clocks. The changed zones are
2363 Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
2364 Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
2365 Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
2366 Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
2367 subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
2368 but not its UTC offset. Two zones are added: Asia/Chita (split
2369 from Asia/Yakutsk, and also with two hours subtracted) and
2370 Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
2371 subtracted). (Thanks to Tim Parenti for much of the above.)
2373 Changes affecting time zone abbreviations
2375 Australian eastern time zone abbreviations are now AEST/AEDT not EST,
2376 and similarly for the other Australian zones. That is, for eastern
2377 standard and daylight saving time the abbreviations are AEST and AEDT
2378 instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
2379 and AWST/AWDT are now used instead of the former CST, CWST, and WST.
2380 This change does not affect UT offsets, only time zone abbreviations.
2381 (Thanks to Rich Tibbett and many others.)
2383 Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
2384 effective 2014-10-26 at 02:00 local time.
2386 The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
2387 has been changed from URUT to XJT. (Thanks to Luther Ma.)
2389 Prefer MSK/MSD for Moscow time in Russia, even in other cities.
2390 Similarly, prefer EET/EEST for eastern European time in Russia.
2392 Change time zone abbreviations in (western) Samoa to use "ST" and
2393 "DT" suffixes, as this is more likely to match common practice.
2394 Prefix "W" to (western) Samoa time when its standard-time offset
2395 disagrees with that of American Samoa.
2397 America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
2399 Time zone abbreviations have been updated for Japan's two time
2400 zones used 1896-1937. JWST now stands for Western Standard
2401 Time, and JCST for Central Standard Time (formerly this was CJT).
2402 These abbreviations are now used for time in Korea, Taiwan,
2403 and Sakhalin while controlled by Japan.
2405 Changes affecting past timestamps
2407 China's five zones have been simplified to two, since the post-1970
2408 differences in the other three seem to have been imaginary. The
2409 zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
2410 removed; backwards-compatibility links still work, albeit with
2411 different behaviors for timestamps before May 1980. Asia/Urumqi's
2412 1980 transition to UT +08 has been removed, so that it is now at
2413 +06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
2414 Treindl sent helpful translations of two papers by Guo Qingsheng.)
2416 Some zones have been turned into links, when they differed from existing
2417 zones only for older UT offsets where data entries were likely invented.
2418 These changes affect UT offsets in pre-1970 timestamps only. This is
2419 similar to the change in release 2013e, except this time for western
2420 Africa. The affected zones are: Africa/Bamako, Africa/Banjul,
2421 Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
2422 Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
2423 Atlantic/St_Helena. This also affects the backwards-compatibility
2424 link Africa/Timbuktu. (Thanks to Alan Barrett, Stephen Colebourne,
2425 Tim Parenti, and David Patte for reporting problems in earlier
2426 versions of this change.)
2428 Asia/Shanghai's pre-standard-time UT offset has been changed from
2429 8:05:57 to 8:05:43, the location of Xujiahui Observatory. Its
2430 transition to standard time has been changed from 1928 to 1901.
2432 Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
2433 then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
2434 In 1946 it observed DST from 05-15 through 09-30; in 1947
2435 from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
2436 (Thanks to Yu-Cheng Chuang.)
2438 Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
2440 Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
2441 10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
2443 Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
2444 period from 1911 to 1950.
2446 Pacific/Chatham has been changed to New Zealand standard time plus
2447 45 minutes for the period before 1957, reflecting a 1956 remark in
2448 the New Zealand parliament.
2450 Europe/Budapest has several pre-1946 corrections: in 1918 the transition
2451 out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
2452 1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
2453 not 04-06 at 02:00; and there was no DST in 1920.
2455 Africa/Accra is now assumed to have observed DST from 1920 through 1935.
2457 Time in Russia before 1927 or so has been corrected by a few seconds in
2458 the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
2459 Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
2460 Europe/Riga. Also, Moscow's location has been changed to its Kilometer 0
2461 point. (Thanks to Vladimir Karpinsky for the Moscow changes.)
2463 Changes affecting data format
2465 A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
2466 The new file's extended format allows multiple country codes per zone.
2467 The older file is still installed but is deprecated; its format is
2468 not changing and it will still be distributed for a while, but new
2469 applications should use the new file.
2471 The new file format simplifies maintenance of obscure locations.
2472 To test this, it adds coverage for the Crozet Islands and the
2473 Scattered Islands. (Thanks to Tobias Conradi and Antoine Leca.)
2475 The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
2476 It is still ASCII now, but commentary about the switch has been added.
2477 The new file 'zone1970.tab' already uses UTF-8.
2479 Changes affecting code
2481 'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
2482 is defined. (Thanks to Elliott Hughes for reporting the problem.)
2484 'zic' no longer mishandles input when ignoring case in locales that
2485 are not compatible with English, e.g., unibyte Turkish locales when
2486 compiled with HAVE_GETTEXT.
2488 Error diagnostics of 'zic' and 'yearistype' have been reworded so that
2489 they no longer use ASCII '-' as if it were a dash.
2491 'zic' now rejects output file names that contain '.' or '..' components.
2492 (Thanks to Tim Parenti for reporting the problem.)
2494 'zic -v' now warns about output file names that do not follow
2495 POSIX rules, or that contain a digit or '.'. (Thanks to Arthur
2496 David Olson for starting the ball rolling on this.)
2498 Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
2500 Changes affecting build procedure
2502 'zic' no longer links in localtime.o and asctime.o, as they're not needed.
2503 (Thanks to John Cochran.)
2505 Changes affecting documentation and commentary
2507 The 'Theory' file documents legacy names, the longstanding
2508 exceptions to the POSIX-inspired file name rules.
2510 The 'zic' documentation clarifies the role of time types when
2511 interpreting dates. (Thanks to Arthur David Olson.)
2513 Documentation and commentary now prefer UTF-8 to US-ASCII,
2514 allowing the use of proper accents in foreign words and names.
2515 Code and data have not changed because of this. (Thanks to
2516 Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
2519 Non-HTML documentation and commentary now use plain-text URLs instead of
2520 HTML insertions, and are more consistent about bracketing URLs when they
2521 are not already surrounded by white space. (Thanks to suggestions by
2524 There is new commentary about Xujiahui Observatory, the five time-zone
2525 project in China from 1918 to 1949, timekeeping in Japanese-occupied
2526 Shanghai, and Tibet Time in the 1950s. The sharp-eyed can spot the
2527 warlord Jin Shuren in the data.
2529 Commentary about the coverage of each Russian zone has been standardized.
2530 (Thanks to Tim Parenti.)
2532 There is new commentary about contemporary timekeeping in Ethiopia.
2534 Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
2536 There is new commentary about time in Poland in 1919.
2538 Proper credit has been given to DST inventor George Vernon Hudson.
2540 Commentary about time in Metlakatla, AK and Resolute, NU has been
2541 improved, with a new source for the former.
2543 In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
2546 Commentary about permanent Antarctic bases has been updated.
2548 Several typos have been corrected. (Thanks to Tim Parenti for
2549 contributing some of these fixes.)
2551 tz-link.htm now mentions the JavaScript libraries Moment Timezone,
2552 TimezoneJS.Date, Walltime-js, and Timezone. (Thanks to a heads-up
2553 from Matt Johnson.) Also, it mentions the Go 'latlong' package.
2554 (Thanks to a heads-up from Dirkjan Ochtman.)
2556 The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
2557 have been removed. These obsolescent US Naval Observatory entries were no
2558 longer helpful for maintenance. (Thanks to Tim Parenti for the suggestion.)
2561 Release 2014e - 2014-06-12 21:53:52 -0700
2563 Changes affecting near-future timestamps
2565 Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
2566 (Thanks to Imed Chihi.) Guess that from 2015 on Egypt will temporarily
2567 switch to standard time at 24:00 the last Thursday before Ramadan, and
2568 back to DST at 00:00 the first Friday after Ramadan.
2570 Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00. (Thanks
2571 to Milamber Space Network.) Guess that from 2015 on Morocco will
2572 temporarily switch to standard time at 03:00 the last Saturday before
2573 Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
2575 Changes affecting past timestamps
2577 The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
2578 "MSD" for Moscow's double daylight time in summer 1921. Also, a typo
2579 "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
2580 in 1991. (Thanks to Hank W. for reporting the problems.)
2582 Changes affecting commentary
2584 tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
2585 draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
2586 removes stale pointers to World Time Explorer and WORLDTIME.
2589 Release 2014d - 2014-05-27 21:34:40 -0700
2591 Changes affecting code
2593 zic no longer generates files containing timestamps before the Big Bang.
2594 This works around GNOME glib bug 878
2595 <https://gitlab.gnome.org/GNOME/glib/issues/878>
2596 (Thanks to Leonardo Chiquitto for reporting the bug, and to
2597 Arthur David Olson and James Cloos for suggesting improvements to the fix.)
2599 Changes affecting documentation
2601 tz-link.htm now mentions GNOME.
2604 Release 2014c - 2014-05-13 07:44:13 -0700
2606 Changes affecting near-future timestamps
2608 Egypt observes DST starting 2014-05-15 at 24:00.
2609 (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
2610 Details have not been announced, except that DST will not be observed
2611 during Ramadan. Guess that DST will stop during the same Ramadan dates as
2612 Morocco, and that Egypt's future spring and fall transitions will be the
2613 same as 2010 when it last observed DST, namely April's last Friday at
2614 00:00 to September's last Thursday at 23:00 standard time. Also, guess
2615 that Ramadan transitions will be at 00:00 standard time.
2617 Changes affecting code
2619 zic now generates transitions for minimum time values, eliminating guesswork
2620 when handling low-valued timestamps. (Thanks to Arthur David Olson.)
2622 Port to Cygwin sans glibc. (Thanks to Arthur David Olson.)
2624 Changes affecting commentary and documentation
2626 Remove now-confusing comment about Jordan. (Thanks to Oleksii Nochovnyi.)
2629 Release 2014b - 2014-03-24 21:28:50 -0700
2631 Changes affecting near-future timestamps
2633 Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
2634 (Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
2636 New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and
2637 Bengt-Inge Larsson.) This is currently an approximation; a better version
2638 will require the zic and localtime fixes mentioned below, and the plan is
2639 to wait for a while until at least the zic fixes propagate.
2641 Changes affecting code
2643 'zic' and 'localtime' no longer reject locations needing four transitions
2644 per year for the foreseeable future. (Thanks to Andrew Main (Zefram).)
2645 Also, 'zic' avoids some unlikely failures due to integer overflow.
2647 Changes affecting build procedure
2649 'make check' now detects Rule lines defined but never used.
2650 The NZAQ rules, an instance of this problem, have been removed.
2652 Changes affecting commentary and documentation
2654 Fix Tuesday/Thursday typo in description of time in Israel.
2655 (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
2657 Microsoft Windows 8.1 doesn't support tz database names. (Thanks
2658 to Donald MacQueen.) Instead, the Microsoft Windows Store app
2659 library supports them.
2661 Add comments about Johnston Island time in the 1960s.
2662 (Thanks to Lyle McElhaney.)
2664 Morocco's 2014 DST start will be as predicted.
2665 (Thanks to Sebastien Willemijns.)
2668 Release 2014a - 2014-03-07 23:30:29 -0800
2670 Changes affecting near-future timestamps
2672 Turkey begins DST on 2014-03-31, not 03-30. (Thanks to Faruk Pasin for
2673 the heads-up, and to Tim Parenti for simplifying the update.)
2675 Changes affecting past timestamps
2677 Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
2678 (Thanks to Steffen Thorsen.)
2680 Ukraine switched from Moscow to Eastern European time on 1990-07-01
2681 (not 1992-01-01), and observed DST during the entire next winter.
2682 (Thanks to Vladimir in Moscow via Alois Treindl.)
2684 In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
2685 (Thanks to Avigdor Finkelstein.)
2687 Changes affecting code
2689 A uninitialized-storage bug in 'localtime' has been fixed.
2690 (Thanks to Logan Chien.)
2692 Changes affecting the build procedure
2694 The settings for 'make check_web' now default to Ubuntu 13.10.
2696 Changes affecting commentary and documentation
2698 The boundary of the US Pacific time zone is given more accurately.
2699 (Thanks to Alan Mintz.)
2701 Chile's 2014 DST will be as predicted. (Thanks to José Miguel Garrido.)
2703 Paraguay's 2014 DST will be as predicted. (Thanks to Carlos Raúl Perasso.)
2705 Better descriptions of countries with same time zone history as
2706 Trinidad and Tobago since 1970. (Thanks to Alan Barrett for suggestion.)
2708 Several changes affect tz-link.htm, the main web page.
2710 Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
2713 Mention xCal (Internet RFC 6321) and jCal.
2715 Microsoft has some support for tz database names.
2717 CLDR data formats include both XML and JSON.
2719 Mention Maggiolo's map of solar vs standard time.
2720 (Thanks to Arthur David Olson.)
2722 Mention TZ4Net. (Thanks to Matt Johnson.)
2724 Mention the timezone-olson Haskell package.
2726 Mention zeitverschiebung.net. (Thanks to Martin Jäger.)
2728 Remove moribund links to daylight-savings-time.info and to
2729 Simple Timer + Clocks.
2731 Update two links. (Thanks to Oscar van Vlijmen.)
2733 Fix some formatting glitches, e.g., remove random newlines from
2734 abbr elements' title attributes.
2737 Release 2013i - 2013-12-17 07:25:23 -0800
2739 Changes affecting near-future timestamps:
2741 Jordan switches back to standard time at 00:00 on December 20, 2013.
2742 The 2006-2011 transition schedule is planned to resume in 2014.
2743 (Thanks to Steffen Thorsen.)
2745 Changes affecting past timestamps:
2747 In 2004, Cuba began DST on March 28, not April 4.
2748 (Thanks to Steffen Thorsen.)
2750 Changes affecting code
2752 The compile-time flag NOSOLAR has been removed, as nowadays the
2753 benefit of slightly shrinking runtime table size is outweighed by the
2754 cost of disallowing potential future updates that exceed old limits.
2756 Changes affecting documentation and commentary
2758 The files solar87, solar88, and solar89 are no longer distributed.
2759 They were a negative experiment - that is, a demonstration that
2760 tz data can represent solar time only with some difficulty and error.
2761 Their presence in the distribution caused confusion, as Riyadh
2762 civil time was generally not solar time in those years.
2764 tz-link.htm now mentions Noda Time. (Thanks to Matt Johnson.)
2767 Release 2013h - 2013-10-25 15:32:32 -0700
2769 Changes affecting current and future timestamps:
2771 Libya has switched its UT offset back to +02 without DST, instead
2772 of +01 with DST. (Thanks to Even Scharning.)
2774 Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
2775 (Thanks to Gwillim Law.)
2777 Changes affecting future timestamps:
2779 Acre and (we guess) western Amazonas will switch from UT -04 to -05
2780 on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
2781 (Thanks to Steffen Thorsen.)
2783 Add entries for DST transitions in Morocco in the year 2038.
2784 This avoids some year-2038 glitches introduced in 2013g.
2785 (Thanks to Yoshito Umaoka for reporting the problem.)
2787 Changes affecting API
2789 The 'tzselect' command no longer requires the 'select' command,
2790 and should now work with /bin/sh on more platforms. It also works
2791 around a bug in BusyBox awk before version 1.21.0. (Thanks to
2792 Patrick 'P. J.' McDermott and Alan Barrett.)
2794 Changes affecting code
2796 Fix localtime overflow bugs with 32-bit unsigned time_t.
2798 zdump no longer assumes sscanf returns maximal values on overflow.
2800 Changes affecting the build procedure
2802 The builder can specify which programs to use, if any, instead of
2803 'ar' and 'ranlib', and libtz.a is now built locally before being
2804 installed. (Thanks to Michael Forney.)
2806 A dependency typo in the 'zdump' rule has been fixed.
2807 (Thanks to Andrew Paprocki.)
2809 The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
2810 work as specified by POSIX.2-1992 or later; this is portable nowadays.
2812 'make clean' no longer removes 'leapseconds', since it's
2813 host-independent and is part of the distribution.
2815 The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
2817 Changes affecting documentation and commentary
2819 tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
2820 (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
2822 Update URLs in tz-link page. Add URLs for Microsoft Windows, since
2823 8.1 introduces tz support. Remove URLs for Tru64 and UnixWare (no
2824 longer maintained) and for old advisories. SOFA now does C.
2826 Release 2013g - 2013-09-30 21:08:26 -0700
2828 Changes affecting current and near-future timestamps
2830 Morocco now observes DST from the last Sunday in March to the last
2831 Sunday in October, not April to September respectively. (Thanks
2832 to Steffen Thorsen.)
2834 Changes affecting 'zic'
2836 'zic' now runs on platforms that lack both hard links and symlinks.
2837 (Thanks to Theo Veenker for reporting the problem, for MinGW.)
2838 Also, fix some bugs on platforms that lack hard links but have symlinks.
2840 'zic -v' again warns that Asia/Tehran has no POSIX environment variable
2841 to predict the far future, fixing a bug introduced in 2013e.
2843 Changes affecting the build procedure
2845 The 'leapseconds' file is again put into the tzdata tarball.
2846 Also, 'leapseconds.awk', so tzdata is self-contained. (Thanks to
2847 Matt Burgess and Ian Abbott.) The timestamps of these and other
2848 dependent files in tarballs are adjusted more consistently.
2850 Changes affecting documentation and commentary
2852 The README file is now part of the data tarball as well as the code.
2853 It now states that files are public domain unless otherwise specified.
2854 (Thanks to Andrew Main (Zefram) for asking for clarifications.)
2855 Its details about the 1989 release moved to a place of honor near
2859 Release 2013f - 2013-09-24 23:37:36 -0700
2861 Changes affecting near-future timestamps
2863 Tocantins will very likely not observe DST starting this spring.
2864 (Thanks to Steffen Thorsen.)
2866 Jordan will likely stay at UT +03 indefinitely, and will not fall
2869 Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
2871 Changes affecting API
2873 The types of the global variables 'timezone' and 'altzone' (if present)
2874 have been changed back to 'long'. This is required for 'timezone'
2875 by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
2876 These variables were originally 'long' in the tz code, but were
2877 mistakenly changed to 'time_t' in 1987; nobody reported the
2878 incompatibility until now. The difference matters on x32, where
2879 'long' is 32 bits and 'time_t' is 64. (Thanks to Elliott Hughes.)
2881 Changes affecting the build procedure
2883 Avoid long strings in leapseconds.awk to work around a mawk bug.
2884 (Thanks to Cyril Baurand.)
2886 Changes affecting documentation and commentary
2888 New file 'NEWS' that contains release notes like this one.
2890 Paraguay's law does not specify DST transition time; 00:00 is customary.
2891 (Thanks to Waldemar Villamayor-Venialbo.)
2893 Minor capitalization fixes.
2895 Changes affecting version-control only
2897 The experimental GitHub repository now contains annotated and
2898 signed tags for recent releases, e.g., '2013e' for Release 2013e.
2899 Releases are tagged starting with 2012e; earlier releases were
2900 done differently, and tags would either not have a simple name or
2901 not exactly match what was released.
2903 'make set-timestamps' is now simpler and a bit more portable.
2906 Release 2013e - 2013-09-19 23:50:04 -0700
2908 Changes affecting near-future timestamps
2910 This year Fiji will start DST on October 27, not October 20.
2911 (Thanks to David Wheeler for the heads-up.) For now, guess that
2912 Fiji will continue to spring forward the Sunday before the fourth
2915 Changes affecting current and future time zone abbreviations
2917 Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
2918 time zone abbreviations since 1932. (Thanks to George Ziegler,
2919 Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
2920 Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
2921 Asia/Makassar, and Asia/Pontianak.
2923 Use ART (UT -03, standard time), rather than WARST (also -03, but
2924 daylight saving time) for San Luis, Argentina since 2009.
2926 Changes affecting Godthåb timestamps after 2037 if version mismatch
2928 Allow POSIX-like TZ strings where the transition time's hour can
2929 range from -167 through 167, instead of the POSIX-required 0
2930 through 24. E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
2931 new Fiji rules. This is a more-compact way to represent
2932 far-future timestamps for America/Godthab, America/Santiago,
2933 Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
2934 Pacific/Easter, and Pacific/Fiji. Other zones are unaffected by
2935 this change. (Derived from a suggestion by Arthur David Olson.)
2937 Allow POSIX-like TZ strings where daylight saving time is in
2938 effect all year. E.g., TZ='WART4WARST,J1/0,J365/25' for Western
2939 Argentina Summer Time all year. This supports a more-compact way
2940 to represent the 2013d data for America/Argentina/San_Luis.
2941 Because of the change for San Luis noted above this change does not
2942 affect the current data. (Thanks to Andrew Main (Zefram) for
2943 suggestions that improved this change.)
2945 Where these two TZ changes take effect, there is a minor extension
2946 to the tz file format in that it allows new values for the
2947 embedded TZ-format string, and the tz file format version number
2948 has therefore been increased from 2 to 3 as a precaution.
2949 Version-2-based client code should continue to work as before for
2950 all timestamps before 2038. Existing version-2-based client code
2951 (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
2952 files, and typically works in practice even for timestamps after
2953 2037; the only known exception is America/Godthab.
2955 Changes affecting timestamps before 1970
2957 Pacific/Johnston is now a link to Pacific/Honolulu. This corrects
2958 some errors before 1947.
2960 Some zones have been turned into links, when they differ from existing
2961 zones only in older data entries that were likely invented or that
2962 differ only in LMT or transitions from LMT. These changes affect
2963 only timestamps before 1943. The affected zones are:
2964 Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
2965 America/Grenada, America/Guadeloupe, America/Marigot,
2966 America/Montserrat, America/St_Barthelemy, America/St_Kitts,
2967 America/St_Lucia, America/St_Thomas, America/St_Vincent,
2968 America/Tortola, and Europe/Vaduz. (Thanks to Alois Treindl for
2969 confirming that the old Europe/Vaduz zone was wrong and the new
2970 link is better for WWII-era times.)
2972 Change Kingston Mean Time from -5:07:12 to -5:07:11. This affects
2973 America/Cayman, America/Jamaica and America/Grand_Turk timestamps
2976 Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
2977 This affects Europe/Zurich timestamps from 1853 to 1894. (Thanks
2980 Change the date of the circa-1850 Zurich transition from 1849-09-12
2981 to 1853-07-16, overriding Shanks with data from Messerli about
2982 postal and telegraph time in Switzerland.
2984 Changes affecting time zone abbreviations before 1970
2986 For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
2987 as Jakarta was called Batavia back then.
2989 Changes affecting API
2991 The 'zic' command now outputs a dummy transition when far-future
2992 data can't be summarized using a TZ string, and uses a 402-year
2993 window rather than a 400-year window. For the current data, this
2994 affects only the Asia/Tehran file. It does not affect any of the
2995 timestamps that this file represents, so zdump outputs the same
2996 information as before. (Thanks to Andrew Main (Zefram).)
2998 The 'date' command has a new '-r' option, which lets you specify
2999 the integer time to display, a la FreeBSD.
3001 The 'tzselect' command has two new options '-c' and '-n', which lets you
3002 select a zone based on latitude and longitude.
3004 The 'zic' command's '-v' option now warns about constructs that
3005 require the new version-3 binary file format. (Thanks to Arthur
3006 David Olson for the suggestion.)
3008 Support for floating-point time_t has been removed.
3009 It was always dicey, and POSIX no longer requires it.
3010 (Thanks to Eric Blake for suggesting to the POSIX committee to
3011 remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
3012 Heninger, Arthur David Olson, and Alois Treindl, for reporting
3013 bugs and elucidating some of the corners of the old floating-point
3016 The signatures of 'offtime', 'timeoff', and 'gtime' have been
3017 changed back to the old practice of using 'long' to represent UT
3018 offsets. This had been inadvertently and mistakenly changed to
3019 'int_fast32_t'. (Thanks to Christos Zoulas.)
3021 The code avoids undefined behavior on integer overflow in some
3022 more places, including gmtime, localtime, mktime and zdump.
3024 Changes affecting the zdump utility
3026 zdump now outputs "UT" when referring to Universal Time, not "UTC".
3027 "UTC" does not make sense for timestamps that predate the introduction
3028 of UTC, whereas "UT", a more-generic term, does. (Thanks to Steve Allen
3029 for clarifying UT vs UTC.)
3031 Data changes affecting behavior of tzselect and similar programs
3033 Country code BQ is now called the more-common name "Caribbean Netherlands"
3034 rather than the more-official "Bonaire, St Eustatius & Saba".
3036 Remove from zone.tab the names America/Montreal, America/Shiprock,
3037 and Antarctica/South_Pole, as they are equivalent to existing
3038 same-country-code zones for post-1970 timestamps. The data entries for
3039 these names are unchanged, so the names continue to work as before.
3041 Changes affecting code internals
3043 zic -c now runs way faster on 64-bit hosts when given large numbers.
3045 zic now uses vfprintf to avoid allocating and freeing some memory.
3047 tzselect now computes the list of continents from the data,
3048 rather than have it hard-coded.
3050 Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
3052 Changes affecting the build procedure
3054 The 'leapseconds' file is now generated automatically from a
3055 new file 'leap-seconds.list', which is a copy of
3056 <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
3057 A new source file 'leapseconds.awk' implements this.
3058 The goal is simplification of the future maintenance of 'leapseconds'.
3060 When building the 'posix' or 'right' subdirectories, if the
3061 subdirectory would be a copy of the default subdirectory, it is
3062 now made a symbolic link if that is supported. This saves about
3063 2 MB of file system space.
3065 The links America/Shiprock and Antarctica/South_Pole have been
3066 moved to the 'backward' file. This affects only nondefault builds
3067 that omit 'backward'.
3069 Changes affecting version-control only
3071 .gitignore now ignores 'date'.
3073 Changes affecting documentation and commentary
3075 Changes to the 'tzfile' man page
3077 It now mentions that the binary file format may be extended in
3078 future versions by appending data.
3080 It now refers to the 'zdump' and 'zic' man pages.
3082 Changes to the 'zic' man page
3084 It lists conditions that elicit a warning with '-v'.
3086 It says that the behavior is unspecified when duplicate names
3087 are given, or if the source of one link is the target of another.
3089 Its examples are updated to match the latest data.
3091 The definition of white space has been clarified slightly.
3092 (Thanks to Michael Deckers.)
3094 Changes to the 'Theory' file
3096 There is a new section about the accuracy of the tz database,
3097 describing the many ways that errors can creep in, and
3098 explaining why so many of the pre-1970 timestamps are wrong or
3099 misleading (thanks to Steve Allen, Lester Caine, and Garrett
3100 Wollman for discussions that contributed to this).
3102 The 'Theory' file describes LMT better (this follows a
3103 suggestion by Guy Harris).
3105 It refers to the 2013 edition of POSIX rather than the 2004 edition.
3107 It's mentioned that excluding 'backward' should not affect the
3108 other data, and it suggests at least one zone.tab name per
3109 inhabited country (thanks to Stephen Colebourne).
3111 Some longstanding restrictions on names are documented, e.g.,
3112 'America/New_York' precludes 'America/New_York/Bronx'.
3114 It gives more reasons for the 1970 cutoff.
3116 It now mentions which time_t variants are supported, such as
3117 signed integer time_t. (Thanks to Paul Goyette for reporting
3118 typos in an experimental version of this change.)
3120 (Thanks to Philip Newton for correcting typos in these changes.)
3122 Documentation and commentary is more careful to distinguish UT in
3123 general from UTC in particular. (Thanks to Steve Allen.)
3125 Add a better source for the Zurich 1894 transition.
3126 (Thanks to Pierre-Yves Berger.)
3128 Update shapefile citations in tz-link.htm. (Thanks to Guy Harris.)
3131 Release 2013d - 2013-07-05 07:38:01 -0700
3133 Changes affecting future timestamps:
3135 Morocco's midsummer transitions this year are July 7 and August 10,
3136 not July 9 and August 8. (Thanks to Andrew Paprocki.)
3138 Israel now falls back on the last Sunday of October.
3139 (Thanks to Ephraim Silverberg.)
3141 Changes affecting past timestamps:
3143 Specify Jerusalem's location more precisely; this changes the pre-1880
3146 Changing affecting metadata only:
3148 Fix typos in the entries for country codes BQ and SX.
3150 Changes affecting code:
3152 Rework the code to fix a bug with handling Australia/Macquarie on
3153 32-bit hosts (thanks to Arthur David Olson).
3155 Port to platforms like NetBSD, where time_t can be wider than long.
3157 Add support for testing time_t types other than the system's.
3158 Run 'make check_time_t_alternatives' to try this out.
3159 Currently, the tests fail for unsigned time_t;
3160 this should get fixed at some point.
3162 Changes affecting documentation and commentary:
3164 Deemphasize the significance of national borders.
3166 Update the zdump man page.
3168 Remove obsolete NOID comment (thanks to Denis Excoffier).
3170 Update several URLs and comments in the web pages.
3172 Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
3174 Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
3177 Release 2013c - 2013-04-19 16:17:40 -0700
3179 Changes affecting current and future timestamps:
3181 Palestine observed DST starting March 29, 2013. (Thanks to
3182 Steffen Thorsen.) From 2013 on, Gaza and Hebron both observe DST,
3183 with the predicted rules being the last Thursday in March at 24:00
3184 to the first Friday on or after September 21 at 01:00.
3186 Assume that the recent change to Paraguay's DST rules is permanent,
3187 by moving the end of DST to the 4th Sunday in March every year.
3188 (Thanks to Carlos Raúl Perasso.)
3190 Changes affecting past timestamps:
3192 Fix some historical data for Palestine to agree with that of
3193 timeanddate.com, as follows:
3195 The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
3198 The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
3201 The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
3203 The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
3205 The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
3207 The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
3209 Fix times of habitation for Macquarie to agree with the Tasmania
3210 Parks & Wildlife Service history, which indicates that permanent
3211 habitation was 1899-1919 and 1948 on.
3213 Changing affecting metadata only:
3215 Macquarie Island is politically part of Australia, not Antarctica.
3216 (Thanks to Tobias Conradi.)
3218 Sort Macquarie more-consistently with other parts of Australia.
3219 (Thanks to Tim Parenti.)
3222 Release 2013b - 2013-03-10 22:33:40 -0700
3224 Changes affecting current and future timestamps:
3226 Haiti uses US daylight-saving rules this year, and presumably future years.
3227 This changes timestamps starting today. (Thanks to Steffen Thorsen.)
3229 Paraguay will end DST on March 24 this year.
3230 (Thanks to Steffen Thorsen.) For now, assume it's just this year.
3232 Morocco does not observe DST during Ramadan;
3233 try to predict Ramadan in Morocco as best we can.
3234 (Thanks to Erik Homoet for the heads-up.)
3236 Changes affecting commentary:
3238 Update URLs in tz-link page. Add URLs for webOS, BB10, iOS.
3239 Update URL for Solaris. Mention Internet RFC 6557.
3240 Update Internet RFCs 2445->5545, 2822->5322.
3241 Switch from FTP to HTTP for Internet RFCs.
3244 Release 2013a - 2013-02-27 09:20:35 -0800
3246 Change affecting binary data format:
3248 The zone offset at the end of version-2-format zone files is now
3249 allowed to be 24:00, as per POSIX.1-2008. (Thanks to Arthur David Olson.)
3251 Changes affecting current and future timestamps:
3253 Chile's 2013 rules, and we guess rules for 2014 and later, will be
3254 the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
3255 (Thanks to Steffen Thorsen and Robert Elz.)
3257 New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
3258 (Thanks to Tobias Conradi and Arthur David Olson.)
3260 Many changes affect historical timestamps before 1940.
3261 These were deduced from: Milne J. Civil time. Geogr J. 1899
3262 Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
3264 Changes affecting the code:
3266 Fix zic bug that mishandled Egypt's 2010 changes (this also affected
3267 the data). (Thanks to Arthur David Olson.)
3269 Fix localtime bug when time_t is unsigned and data files were generated
3270 by a signed time_t system. (Thanks to Doug Bailey for reporting and
3271 to Arthur David Olson for fixing.)
3273 Allow the email address for bug reports to be set by the packager.
3274 The default is tz@iana.org, as before. (Thanks to Joseph S. Myers.)
3276 Update HTML checking to be compatible with Ubuntu 12.10.
3278 Check that files are a safe subset of ASCII. At some point we may
3279 relax this requirement to a safe subset of UTF-8. Without the
3280 check, some non-UTF-8 encodings were leaking into the distribution.
3284 Restore a comment about copyright notices that was inadvertently deleted.
3285 (Thanks to Arthur David Olson.)
3287 Improve the commentary about which districts observe what times
3288 in Russia. (Thanks to Oscar van Vlijmen and Arthur David Olson.)
3290 Add web page links to tz.js.
3292 Add "Run by the Monkeys" to tz-art. (Thanks to Arthur David Olson.)
3295 Release 2012j - 2012-11-12 18:34:49 -0800
3297 Libya moved to CET this weekend, but with DST planned next year.
3298 (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
3300 Signatures now have the extension .asc, not .sign, as that's more
3301 standard. (Thanks to Phil Pennock.)
3303 The output of 'zdump --version', and of 'zic --version', now
3304 uses a format that is more typical for --version.
3305 (Thanks to Joseph S. Myers.)
3307 The output of 'tzselect --help', 'zdump --help', and 'zic --help'
3308 now uses tz@iana.org rather than the old elsie address.
3310 zic -v now complains about abbreviations that are less than 3
3311 or more than 6 characters, as per Posix. Formerly, it checked
3312 for abbreviations that were more than 3.
3314 'make public' no longer puts its temporary directory under /tmp,
3315 and uses the just-built zic rather than the system zic.
3317 Various fixes to documentation and commentary.
3320 Release 2012i - 2012-11-03 12:57:09 -0700
3322 Cuba switches from DST tomorrow at 01:00. (Thanks to Steffen Thorsen.)
3324 Linker flags can now be specified via LDFLAGS.
3325 AWK now defaults to 'awk', not 'nawk'.
3326 The shell in tzselect now defaults to /bin/bash, but this can
3327 be overridden by specifying KSHELL.
3328 The main web page now mentions the unofficial GitHub repository.
3329 (Thanks to Mike Frysinger.)
3331 Tarball signatures can now be built by running 'make signatures'.
3332 There are also new makefile rules 'tarballs', 'check_public', and
3333 separate makefile rules for each tarball and signature file.
3334 A few makefile rules are now more portable to strict POSIX.
3336 The main web page now lists the canonical IANA URL.
3339 Release 2012h - 2012-10-26 22:49:10 -0700
3341 Bahia no longer has DST. (Thanks to Kelley Cook.)
3343 Tocantins has DST. (Thanks to Rodrigo Severo.)
3345 Israel has new DST rules next year. (Thanks to Ephraim Silverberg.)
3347 Jordan stays on DST this winter. (Thanks to Steffen Thorsen.)
3351 More C modernization, except that at Arthur David Olson's suggestion
3352 the instances of 'register' were kept.
3355 Release 2012g - 2012-10-17 20:59:45 -0700
3357 Samoa fall 2012 and later. (Thanks to Nicholas Pereira and Robert Elz.)
3359 Palestine fall 2012. (Thanks to Steffen Thorsen.)
3363 To attack the version-number problem, this release ships the file
3364 'Makefile' (which contains the release number) in both the tzcode and
3365 the tzdata tarballs. The two Makefiles are identical, and should be
3366 identical in any matching pair of tarballs, so it shouldn't matter
3367 which order you extract the tarballs. Perhaps we can come up with a
3368 better version-number scheme at some point; this scheme does have the
3369 virtue of not adding more files.
3372 Release 2012f - 2012-09-12 23:17:03 -0700
3374 * australasia (Pacific/Fiji): Fiji DST is October 21 through January
3375 20 this year. (Thanks to Steffen Thorsen.)
3378 Release 2012e - 2012-08-02 20:44:55 -0700
3380 * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
3381 (Thanks to Steffen Thorsen.)
3383 * Use a single version number for both code and data.
3385 * .gitignore: New file.
3387 * Remove trailing white space.
3390 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
3392 Changes for Morocco's timestamps, which take effect in a couple of
3393 hours, along with infrastructure changes to accommodate how the tz
3394 code and data are released on IANA.
3397 Release data2012c - 2012-03-27 12:17:25 -0400
3400 Summer time changes for Morocco (to start late April 2012)
3403 Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
3406 Haiti following US/Canada rules for 2012 (and we're assuming,
3407 for now anyway, for the future).
3410 Release 2012b - 2012-03-02 12:29:15 +0700
3412 There is just one change to tzcode2012b (compared with 2012a):
3413 the Makefile that was accidentally included with 2012a has been
3414 replaced with the version that should have been there, which is
3415 identical with the previous version (from tzcode2011i).
3417 There are just two changes in tzdata2012b compared with 2012a.
3419 Most significantly, summer time in Cuba has been delayed 3 weeks
3420 (now starts April 1 rather than March 11). Since Mar 11 (the old start
3421 date, as listed in 2012a) is just a little over a week away, this
3424 Less importantly, an excess tab in one of the changes in zone.tab
3425 in 2012a has been removed.
3428 Release 2012a - 2012-03-01 18:28:10 +0700
3430 The changes in tzcode2012a (compared to the previous version, 2011i)
3431 are entirely to the README and tz-art.htm and tz-link.htm files, if
3432 none of those concern you, you can ignore the code update. The changes
3433 reflect the changed addresses for the mailing list and the code and
3434 data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
3435 has been added to tz-link.htm).
3437 In tzdata2012a (compared to the previous release, which was 2011n)
3438 the major changes are:
3439 Chile 2011/2012 and 2012/2013 summer time date adjustments.
3440 Falkland Islands onto permanent summer time (we're assuming for the
3441 foreseeable future, though 2012 is all we're fairly certain of.)
3442 Armenia has abolished Summer Time.
3443 Tokelau jumped the International Date Line back last December
3444 (just the same as their near neighbour, Samoa).
3445 America/Creston is a new zone for a small area of British Columbia
3446 There will be a leapsecond 2012-06-30 23:59:60 UTC.
3448 Other minor changes are:
3449 Corrections to 1918 Canadian summer time end dates.
3450 Updated URL for UK time zone history (in comments)
3451 A few typos in Le Corre's list of free French place names (comments)
3454 Release data2011n - 2011-10-30 14:57:54 +0700
3456 There are three changes of note - most urgently, Cuba (America/Havana)
3457 has extended summer time by two weeks, now to end on Nov 13, rather than
3458 the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic
3459 (Europe/Tiraspol) decided not to split from the rest of Moldova after
3460 all, and consequently that zone has been removed (again) and reinstated
3461 in the "backward" file as a link to Europe/Chisinau. And third, the
3462 end date for Fiji's summer time this summer was moved forward from the
3463 earlier planned Feb 26, to Jan 22.
3465 Apart from that, Moldova (MD) returns to a single entry in zone.tab
3466 (and the incorrect syntax that was in the 2011m version of that file
3467 is so fixed - it would have been fixed in a different way had this
3468 change not happened - that's the "missing" sccs version id).
3471 Release data2011m - 2011-10-24 21:42:16 +0700
3473 In particular, the typos in comments in the data (2011-11-17 should have
3474 been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
3475 Tim Parenti noted) have been fixed, and the change for Ukraine has been
3476 made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
3477 Tim Parenti, and also Denys Gavrysh)
3479 In addition, I added Europe/Tiraspol to zone.tab.
3481 This time, all the files have new version numbers... (including the files
3482 otherwise unchanged in 2011m that were changed in 2011l but didn't get new
3483 version numbers there...)
3486 Release data2011l - 2011-10-10 11:15:43 +0700
3488 There are just 2 changes that cause different generated tzdata files from
3489 zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
3490 is included, but commented out. Compared with the diff I sent out last week,
3491 this version also includes attributions for the sources for the changes
3492 (in much the same format as ado used, but the html tags have not been
3493 checked, verified, or used in any way at all, so if there are errors there,
3494 please let me know.)
3497 Release data2011k - 2011-09-20 17:54:03 -0400
3502 Release data2011j - 2011-09-12 09:22:49 -0400
3504 (contemporary changes for Samoa; past changes for Kenya, Uganda, and
3505 Tanzania); there are also two spelling corrections to comments in
3506 the australasia file (with thanks to Christos Zoulas).
3509 Release 2011i - 2011-08-29 05:56:32 -0400
3514 Release data2011h - 2011-06-15 18:41:48 -0400
3516 Russia and Curaçao changes
3519 Release 2011g - 2011-04-25 09:07:22 -0400
3521 update the rules for Egypt to reflect its abandonment of DST this year
3524 Release 2011f - 2011-04-06 17:14:53 -0400
3529 Release 2011e - 2011-03-31 16:04:38 -0400
3531 Morocco, Chile, and tz-link changes
3534 Release 2011d - 2011-03-14 09:18:01 -0400
3536 changes that impact present-day timestamps in Cuba, Samoa, and Turkey
3539 Release 2011c - 2011-03-07 09:30:09 -0500
3541 These do affect current timestamps in Chile and Annette Island, Canada.
3544 Release 2011b - 2011-02-07 08:44:50 -0500
3549 Release 2011a - 2011-01-24 10:30:16 -0500
3554 Release data2010o - 2010-11-01 09:18:23 -0400
3556 change to the end of DST in Fiji in 2011
3559 Release 2010n - 2010-10-25 08:19:17 -0400
3564 Release 2010m - 2010-09-27 09:24:48 -0400
3566 Hong Kong, Vostok, and zic.c changes
3569 Release 2010l - 2010-08-16 06:57:25 -0400
3574 Release 2010k - 2010-07-26 10:42:27 -0400
3579 Release 2010j - 2010-05-10 09:07:48 -0400
3581 changes for Bahía de Banderas and for version naming
3584 Release data2010i - 2010-04-16 18:50:45 -0400
3586 the end of DST in Morocco on 2010-08-08
3589 Release data2010h - 2010-04-05 09:58:56 -0400
3594 Release data2010g - 2010-03-24 11:14:53 -0400
3599 Release 2010f - 2010-03-22 09:45:46 -0400
3604 Release data2010e - 2010-03-08 14:24:27 -0500
3606 corrects the Dhaka bug found by Danvin Ruangchan
3609 Release data2010d - 2010-03-06 07:26:01 -0500
3614 Release 2010c - 2010-03-01 09:20:58 -0500
3616 changes including KRE's suggestion for earlier initialization of
3617 "goahead" and "goback" structure elements
3620 Release code2010a - 2010-02-16 10:40:04 -0500
3625 Release data2010b - 2010-01-20 12:37:01 -0500
3630 Release data2010a - 2010-01-18 08:30:04 -0500
3635 Release data2009u - 2009-12-26 08:32:28 -0500
3637 changes to DST in Bangladesh
3640 Release 2009t - 2009-12-21 13:24:27 -0500
3645 Release data2009s - 2009-11-14 10:26:32 -0500
3647 (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
3650 Release 2009r - 2009-11-09 10:10:31 -0500
3652 "antarctica" and "tz-link.htm" changes
3655 Release 2009q - 2009-11-02 09:12:40 -0500
3657 with two corrections as reported by Eric Muller and Philip Newton
3660 Release data2009p - 2009-10-23 15:05:27 -0400
3662 Argentina (including San Luis) changes (with the correction from
3666 Release data2009o - 2009-10-14 16:49:38 -0400
3668 Samoa (commentary only), Pakistan, and Bangladesh changes
3671 Release data2009n - 2009-09-22 15:13:38 -0400
3673 added commentary for Argentina and a change to the end of DST in
3677 Release data2009m - 2009-09-03 10:23:43 -0400
3679 Samoa and Palestine changes
3682 Release data2009l - 2009-08-14 09:13:07 -0400
3684 Samoa (comments only) and Egypt
3687 Release 2009k - 2009-07-20 09:46:08 -0400
3692 Release data2009j - 2009-06-15 06:43:59 -0400
3694 Bangladesh change (with a short turnaround since the DST change is
3698 Release 2009i - 2009-06-08 09:21:22 -0400
3700 updating for DST in Bangladesh this year
3703 Release 2009h - 2009-05-26 09:19:14 -0400
3708 Release data2009g - 2009-04-20 16:34:07 -0400
3713 Release data2009f - 2009-04-10 11:00:52 -0400
3715 correct DST in Pakistan
3718 Release 2009e - 2009-04-06 09:08:11 -0400
3723 Release 2009d - 2009-03-23 09:38:12 -0400
3725 Morocco, Tunisia, Argentina, and American Astronomical Society changes
3728 Release data2009c - 2009-03-16 09:47:51 -0400
3730 change to the start of Cuban DST
3733 Release 2009b - 2009-02-09 11:15:22 -0500
3738 Release 2009a - 2009-01-21 10:09:39 -0500
3743 Release data2008i - 2008-10-21 12:10:25 -0400
3745 southamerica and zone.tab files, with Argentina DST rule changes and
3746 United States zone reordering and recommenting
3749 Release 2008h - 2008-10-13 07:33:56 -0400
3754 Release 2008g - 2008-10-06 09:03:18 -0400
3756 Fix a broken HTML anchor and update Brazil's DST transitions;
3757 there's also a slight reordering of information in tz-art.htm.
3760 Release data2008f - 2008-09-09 22:33:26 -0400
3765 Release 2008e - 2008-07-28 14:11:17 -0400
3767 changes by Arthur David Olson and Jesper Nørgaard Welen
3770 Release data2008d - 2008-07-07 09:51:38 -0400
3772 changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
3775 Release data2008c - 2008-05-19 17:48:03 -0400
3777 Pakistan, Morocco, and Mongolia
3780 Release data2008b - 2008-03-24 08:30:59 -0400
3782 including renaming Asia/Calcutta to Asia/Kolkata, with a backward
3786 Release 2008a - 2008-03-08 05:42:16 -0500
3791 Release 2007k - 2007-12-31 10:25:22 -0500
3793 most importantly, changes to the "southamerica" file based on
3794 Argentina's readoption of daylight saving time
3797 Release 2007j - 2007-12-03 09:51:01 -0500
3799 1. eliminate the "P" (parameter) macro;
3801 2. the "noncontroversial" changes circulated on the time zone
3802 mailing list (less the changes to "logwtmp.c");
3804 3. eliminate "too many transition" errors when "min" is used in time
3807 4. changes by Paul Eggert (including updated information for Venezuela).
3810 Release data2007i - 2007-10-30 10:28:11 -0400
3812 changes for Cuba and Syria
3815 Release 2007h - 2007-10-01 10:05:51 -0400
3817 changes by Paul Eggert, as well as an updated link to the ICU
3818 project in tz-link.htm
3821 Release 2007g - 2007-08-20 10:47:59 -0400
3823 changes by Paul Eggert
3825 The "leapseconds" file has been updated to incorporate the most
3826 recent International Earth Rotation and Reference Systems Service
3829 There's an addition to tz-art.htm regarding the television show "Medium".
3832 Release 2007f - 2007-05-07 10:46:46 -0400
3834 changes by Paul Eggert (including Haiti, Turks and Caicos, and New
3837 changes to zic.c to allow hour values greater than 24 (along with
3838 Paul's improved time value overflow checking)
3841 Release 2007e - 2007-04-02 10:11:52 -0400
3843 Syria and Honduras changes by Paul Eggert
3845 zic.c variable renaming changes by Arthur David Olson
3848 Release 2007d - 2007-03-20 08:48:30 -0400
3850 changes by Paul Eggert
3852 the elimination of white space at the ends of lines
3855 Release 2007c - 2007-02-26 09:09:37 -0500
3857 changes by Paul Eggert
3860 Release 2007b - 2007-02-12 09:34:20 -0500
3862 Paul Eggert's proposed change to the quotation handling logic in zic.c.
3864 changes to the commentary in "leapseconds" reflecting the IERS
3865 announcement that there is to be no positive leap second at the end
3869 Release 2007a - 2007-01-08 12:28:29 -0500
3871 changes by Paul Eggert
3873 Derick Rethan's Asmara change
3875 Oscar van Vlijmen's Easter Island local mean time change
3877 symbolic link changes
3880 Release 2006p - 2006-11-27 08:54:27 -0500
3882 changes by Paul Eggert
3885 Release 2006o - 2006-11-06 09:18:07 -0500
3887 changes by Paul Eggert
3890 Release 2006n - 2006-10-10 11:32:06 -0400
3892 changes by Paul Eggert
3895 Release 2006m - 2006-10-02 15:32:35 -0400
3897 changes for Uruguay, Palestine, and Egypt by Paul Eggert
3899 (minimalist) changes to zic.8 to clarify "until" information
3902 Release data2006l - 2006-09-18 12:58:11 -0400
3904 Paul's best-effort work on this coming weekend's Egypt time change
3907 Release 2006k - 2006-08-28 12:19:09 -0400
3909 changes by Paul Eggert
3912 Release 2006j - 2006-08-21 09:56:32 -0400
3914 changes by Paul Eggert
3917 Release code2006i - 2006-08-07 12:30:55 -0400
3921 Ken Pizzini's conversion script
3924 Release code2006h - 2006-07-24 09:19:37 -0400
3926 adds public domain notices to four files
3928 includes a fix for transition times being off by a second
3930 adds a new recording to the "arts" file (information courtesy Colin Bowern)
3933 Release 2006g - 2006-05-08 17:18:09 -0400
3935 northamerica changes by Paul Eggert
3938 Release 2006f - 2006-05-01 11:46:00 -0400
3940 a missing version number problem is fixed (with thanks to Bradley
3941 White for catching the problem)
3944 Release 2006d - 2006-04-17 14:33:43 -0400
3946 changes by Paul Eggert
3948 added new items to tz-arts.htm that were found by Paul
3951 Release 2006c - 2006-04-03 10:09:32 -0400
3953 two sets of data changes by Paul Eggert
3955 a fencepost error fix in zic.c
3957 changes to zic.c and the "europe" file to minimize differences
3958 between output produced by the old 32-bit zic and the new 64-bit
3962 Release 2006b - 2006-02-20 10:08:18 -0500
3963 [tz32code2006b + tz64code2006b + tzdata2006b]
3967 All SCCS IDs were bumped to "8.1" for this release.
3970 Release 2006a - 2006-01-30 08:59:31 -0500
3972 changes by Paul Eggert (in particular, Indiana time zone moves)
3974 an addition to the zic manual page to describe how special-case
3975 transitions are handled
3978 Release 2005r - 2005-12-27 09:27:13 -0500
3980 Canadian changes by Paul Eggert
3982 They also add "<pre>" directives to time zone data files and reflect
3983 changes to warning message logic in "zdump.c" (but with calls to
3984 "gettext" kept unbundled at the suggestion of Ken Pizzini).
3987 Release 2005q - 2005-12-13 09:17:09 -0500
3989 Nothing earth-shaking here:
3990 1. Electronic mail addresses have been removed.
3991 2. Casts of the return value of exit have been removed.
3992 3. Casts of the argument of is.* macros have been added.
3993 4. Indentation in one section of zic.c has been fixed.
3994 5. References to dead URLs in the data files have been dealt with.
3997 Release 2005p - 2005-12-05 10:30:53 -0500
3999 "systemv", "tz-link.htm", and "zdump.c" changes
4000 (less the casts of arguments to the is* macros)
4003 Release 2005o - 2005-11-28 10:55:26 -0500
4005 Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
4007 zdump.c lint fixes by Arthur David Olson
4010 Release 2005n - 2005-10-03 09:44:09 -0400
4012 changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
4016 Release 2005m - 2005-08-29 12:15:40 -0400
4018 changes by Paul Eggert (with a small tweak to the tz-art change)
4020 a declaration of an unused variable has been removed from zdump.c
4023 Release 2005l - 2005-08-22 12:06:39 -0400
4025 changes by Paul Eggert
4027 overflow/underflow checks by Arthur David Olson, minus changes to
4028 the "Theory" file about the pending addition of 64-bit data (I grow
4029 less confident of the changes being accepted with each passing day,
4030 and the changes no longer increase the data files nine-fold--there's
4031 less than a doubling in size by my local Sun's reckoning)
4034 Release 2005k - 2005-07-14 14:14:24 -0400
4036 The "leapseconds" file has been edited to reflect the recently
4037 announced leap second at the end of 2005.
4039 I've also deleted electronic mail addresses from the files as an
4043 Release 2005j - 2005-06-13 14:34:13 -0400
4045 These reflect changes to limit the length of time zone abbreviations
4046 and the characters used in those abbreviations.
4048 There are also changes to handle POSIX-style "quoted" timezone
4049 environment variables.
4051 The changes were circulated on the time zone mailing list; the only
4052 change since then was the removal of a couple of minimum-length of
4053 abbreviation checks.
4056 Release data2005i - 2005-04-21 15:04:16 -0400
4058 changes (most importantly to Nicaragua and Haiti) by Paul Eggert
4061 Release 2005h - 2005-04-04 11:24:47 -0400
4063 changes by Paul Eggert
4065 minor changes to Makefile and zdump.c to produce more useful output
4066 when doing a "make typecheck"
4069 Release 2005g - 2005-03-14 10:11:21 -0500
4071 changes by Paul Eggert (a change to current DST rules in Uruguay and
4072 an update to a link to time zone software)
4075 Release 2005f - 2005-03-01 08:45:32 -0500
4077 data and documentation changes by Paul Eggert
4080 Release 2005e - 2005-02-10 15:59:44 -0500
4085 Release code2005d - 2005-01-31 09:21:47 -0500
4087 make zic complain about links to links if the -v flag is used
4089 have "make public" do more code checking
4091 add an include to "localtime.c" for the benefit of gcc systems
4094 Release 2005c - 2005-01-17 18:36:29 -0500
4096 get better results when mktime runs on a system where time_t is double
4098 changes to the data files (most importantly to Paraguay)
4101 Release 2005b - 2005-01-10 09:19:54 -0500
4103 Get localtime and gmtime working on systems with exotic time_t types.
4105 Update the leap second commentary in the "leapseconds" file.
4108 Release 2005a - 2005-01-01 13:13:44 -0500
4113 Release code2004i - 2004-12-14 13:42:58 -0500
4115 Deal with systems where time_t is unsigned.
4118 Release code2004h - 2004-12-07 11:40:18 -0500
4120 64-bit-time_t changes
4123 Release 2004g - 2004-11-02 09:06:01 -0500
4125 update to Cuba (taking effect this weekend)
4127 other changes by Paul Eggert
4129 correction of the spelling of Oslo
4131 changed versions of difftime.c and private.h
4134 Release code2004f - 2004-10-21 10:25:22 -0400
4136 Cope with wide-ranging tm_year values.
4139 Release 2004e - 2004-10-11 14:47:21 -0400
4141 Brazil/Argentina/Israel changes by Paul Eggert
4143 changes to tz-link.htm by Paul
4145 one small fix to Makefile
4148 Release 2004d - 2004-09-22 08:27:29 -0400
4150 Avoid overflow problems when TM_YEAR_BASE is added to an integer.
4153 Release 2004c - 2004-08-11 12:06:26 -0400
4155 asctime-related changes
4157 (variants of) some of the documentation changes suggested by Paul Eggert
4160 Release 2004b - 2004-07-19 14:33:35 -0400
4162 data changes by Paul Eggert - most importantly, updates for Argentina
4165 Release 2004a - 2004-05-27 12:00:47 -0400
4167 changes by Paul Eggert
4169 Handle DST transitions that occur at the end of a month in some
4170 years but at the start of the following month in other years.
4172 Add a copy of the correspondence that's the basis for claims about
4173 DST in the Navajo Nation.
4176 Release 2003e - 2003-12-15 09:36:47 -0500
4178 changes by Arthur David Olson (primarily code changes)
4180 changes by Paul Eggert (primarily data changes)
4182 minor changes to "Makefile" and "northamerica" (in the latter case,
4183 optimization of the "Toronto" rules)
4186 Release 2003d - 2003-10-06 09:34:44 -0400
4188 changes by Paul Eggert
4191 Release 2003c - 2003-09-16 10:47:05 -0400
4193 Fix bad returns in zic.c's inleap function.
4194 Thanks to Bradley White for catching the problem!
4197 Release 2003b - 2003-09-16 07:13:44 -0400
4199 Add a "--version" option (and documentation) to the zic and zdump commands.
4201 changes to overflow/underflow checking in zic
4203 a localtime typo fix.
4205 Update the leapseconds and tz-art.htm files.
4208 Release 2003a - 2003-03-24 09:30:54 -0500
4210 changes by Paul Eggert
4212 a few additions and modifications to the tz-art.htm file
4215 Release 2002d - 2002-10-15 13:12:42 -0400
4217 changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
4219 There's also a new time zone quote in "tz-art.htm".
4222 Release 2002c - 2002-04-04 11:55:20 -0500
4224 changes by Paul Eggert
4226 Change zic.c to avoid creating symlinks to files that don't exist.
4229 Release 2002b - 2002-01-28 12:56:03 -0500
4231 [These change notes are for Release 2002a, which was corrupted.
4232 2002b was a corrected version of 2002a.]
4234 changes by Paul Eggert
4236 Update the "leapseconds" file to note that there'll be no leap
4237 second at the end of June, 2002.
4239 Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
4241 Change to "difftime.c" to avoid sizeof problems.
4244 Release 2001d - 2001-10-09 13:31:32 -0400
4246 changes by Paul Eggert
4249 Release 2001c - 2001-06-05 13:59:55 -0400
4251 changes by Paul Eggert and Andrew Brown
4254 Release 2001b - 2001-04-05 16:44:38 -0400
4256 changes by Paul Eggert (modulo jnorgard's typo fix)
4258 tz-art.htm has been HTMLified.
4261 Release 2001a - 2001-03-13 12:57:44 -0500
4263 changes by Paul Eggert
4265 An addition to the "leapseconds" file: comments with the text of the
4266 latest IERS leap second notice.
4268 Trailing white space has been removed from data file lines, and
4269 repeated spaces in "Rule Jordan" lines in the "asia" file have been
4273 Release 2000h - 2000-12-14 15:33:38 -0500
4275 changes by Paul Eggert
4277 one typo fix in the "art" file
4279 With providence, this is the last update of the millennium.
4282 Release 2000g - 2000-10-10 11:35:22 -0400
4284 changes by Paul Eggert
4286 correction of John Mackin's name submitted by Robert Elz
4288 Garry Shandling's Daylight Saving Time joke (!?!) from the recent
4289 Emmy Awards broadcast.
4292 Release 2000f - 2000-08-10 09:31:58 -0400
4294 changes by Paul Eggert
4296 Added information in "tz-art.htm" on a Seinfeld reference to DST.
4298 Error checking and messages in the "yearistype" script have been
4302 Release 2000e - 2000-07-31 09:27:54 -0400
4304 data changes by Paul Eggert
4306 a change to the default value of the defined constant HAVE_STRERROR
4308 the addition of a Dave Barry quote on DST to the tz-arts file
4311 Release 2000d - 2000-04-20 15:43:04 -0400
4313 changes to the documentation and code of strftime for C99 conformance
4315 a bug fix for date.c
4317 These are based on (though modified from) changes by Paul Eggert.
4320 Release 2000c - 2000-03-04 10:31:43 -0500
4322 changes by Paul Eggert
4325 Release 2000b - 2000-02-21 12:16:29 -0500
4327 changes by Paul Eggert and Joseph Myers
4329 modest tweaks to the tz-art.htm and tz-link.htm files
4332 Release 2000a - 2000-01-18 09:21:26 -0500
4334 changes by Paul Eggert
4336 The two hypertext documents have also been renamed.
4339 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
4341 Paul Eggert's changes
4343 additions to the "zic" manual page and the "Arts.htm" file
4346 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
4351 Release data1999h - 1999-10-07 03:50:29 -0400
4353 changes by Paul Eggert to "europe" (most importantly, fixing
4354 Lithuania and Estonia)
4357 Release 1999g - 1999-09-28 11:06:18 -0400
4359 data changes by Paul Eggert (most importantly, the change for
4360 Lebanon that buys correctness for this coming Sunday)
4362 The "code" file contains changes to "Makefile" and "checktab.awk" to
4363 allow better checking of time zone files before they are published.
4366 Release 1999f - 1999-09-23 09:48:14 -0400
4368 changes by Arthur David Olson and Paul Eggert
4371 Release 1999e - 1999-08-17 15:20:54 -0400
4373 changes circulated by Paul Eggert, although the change to handling
4374 of DST-specifying timezone names has been commented out for now
4375 (search for "XXX" in "localtime.c" for details). These files also
4376 do not make any changes to the start of DST in Brazil.
4378 In addition to Paul's changes, there are updates to "Arts.htm" and
4382 Release 1999d - 1999-03-30 11:31:07 -0500
4384 changes by Paul Eggert
4386 The Makefile's "make public" rule has also been changed to do a test
4387 compile of each individual time zone data file (which should help
4388 avoid problems such as the one we had with Nicosia).
4391 Release 1999c - 1999-03-25 09:47:47 -0500
4393 changes by Paul Eggert, most importantly the change for Chile.
4396 Release 1999b - 1999-02-01 17:51:44 -0500
4398 changes by Paul Eggert
4400 code changes (suggested by Mani Varadarajan, mani at be.com) for
4401 correct handling of symbolic links when building using a relative directory
4403 code changes to generate correct messages for failed links
4405 updates to the URLs in Arts.htm
4408 Release 1999a - 1999-01-19 16:20:29 -0500
4410 error message internationalizations and corrections in zic.c and
4411 zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
4415 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
4417 changes for Brazil, Chile, and Germany
4419 support for use of "24:00" in the input files for the time zone compiler
4422 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
4424 changes by Paul Eggert
4426 correction to a define in the "private.h" file
4429 Release data1998g - 1998-08-11 03:28:35 -0000
4430 [tzdata1998g.tar.gz is missing!]
4432 Lithuanian change provided by mgedmin at pub.osf.it
4434 Move creation of the GMT link with Etc/GMT to "etcetera" (from
4435 "backward") to ensure that the GMT file is created even where folks
4436 don't want the "backward" links (as suggested by Paul Eggert).
4439 Release data1998f - 1998-07-20 13:50:00 -0000
4440 [tzdata1998f.tar.gz is missing!]
4442 Update the "leapseconds" file to include the newly-announced
4443 insertion at the end of 1998.
4446 Release code1998f - 1998-06-01 10:18:31 -0400
4448 addition to localtime.c by Guy Harris
4451 Release 1998e - 1998-05-28 09:56:26 -0400
4453 The Makefile is changed to produce zoneinfo-posix rather than
4454 zoneinfo/posix, and to produce zoneinfo-leaps rather than
4457 data changes by Paul Eggert
4459 changes from Guy Harris to provide asctime_r and ctime_r
4461 A usno1998 file (substantially identical to usno1997) has been added.
4464 Release 1998d - 1998-05-14 11:58:34 -0400
4466 changes to comments (in particular, elimination of references to CIA maps).
4467 "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
4468 where changes occur.
4471 Release 1998c - 1998-02-28 12:32:26 -0500
4473 changes by Paul Eggert (save the "French correction," on which I'll
4474 wait for the dust to settle)
4478 changes and additions to Arts.htm
4481 Release 1998b - 1998-01-17 14:31:51 -0500
4483 URL cleanups and additions
4486 Release 1998a - 1998-01-13 12:37:35 -0500
4488 changes by Paul Eggert
4491 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
4493 changes by Paul Eggert, with minor modifications from Arthur David
4494 Olson to make the files more browser friendly
4497 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
4499 minor changes to put "TZif" at the start of each timezone information file
4501 a rule has also been added to the Makefile so you can
4503 to just recompile the zone information files (rather than doing a
4504 full "make install" with its other effects).
4507 Release data1997i - 1997-10-07 08:45:38 -0400
4509 changes to Africa by Paul Eggert
4512 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
4514 corrections for Uruguay (and other locations)
4516 Arthur David Olson's simple-minded fix allowing mktime to both
4517 correctly handle leap seconds and correctly handle tm_sec values
4518 upon which arithmetic has been performed.
4521 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
4523 Paul Eggert's updates
4525 a small change to a function prototype;
4527 "Music" has been renamed "Arts.htm", HTMLified, and augmented to
4528 include information on Around the World in Eighty Days.
4531 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
4533 fixes to zic's error handling
4535 changes inspired by the item circulated on Slovenia
4537 The description of Web resources has been HTMLified for browsing
4540 A new piece of tz-related music has been added to the "Music" file.
4543 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
4545 Paul Eggert's latest suggestions
4548 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
4550 changes to "zic.c" to correct performance of the "-s" option
4552 a new file "usno1997"
4555 Release data1997c - 1997-03-04 09:58:18 -0500
4560 Release 1997b - 1997-02-27 18:34:19 -0500
4562 The data file incorporates the 1997 leap second.
4564 The code file incorporates Arthur David Olson's take on the
4565 zic/multiprocessor/directory-creation situation.
4568 Release 1997a - 1997-01-21 09:11:10 -0500
4570 Paul Eggert's Antarctica (and other changes)
4572 Arthur David Olson finessed the "getopt" issue by checking against
4573 both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
4574 is returned while SunOS 5.5's manual says EOF is returned).
4577 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
4579 Paul Eggert's latest changes
4582 Release code1996n - 1996-12-16 09:42:02 -0500
4584 link snapping fix from Bruce Evans (via Garrett Wollman)
4587 Release data1996m - 1996-11-24 02:37:34 -0000
4588 [tzdata1996m.tar.gz is missing!]
4590 Paul Eggert's batch of changes
4593 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
4595 No functional changes here; the files have simply been changed to
4596 make more use of ISO style dates in comments. The names of the above
4597 files now include the year in full.
4600 Release code96l - 1996-09-08 17:12:20 -0400
4602 tzcode96k was missing a couple of pieces.
4605 Release 96k - 1996-09-08 16:06:22 -0400
4607 the latest round of changes from Paul Eggert
4609 the recent Year 2000 material
4612 Release code96j - 1996-07-30 13:18:53 -0400
4614 Set sp->typecnt as suggested by Timothy Patrick Murphy.
4617 Release code96i - 1996-07-27 20:11:35 -0400
4619 Paul's suggested patch for strftime %V week numbers
4622 Release data96i - 1996-07-01 18:13:04 -0400
4624 "northamerica" and "europe" changes by Paul Eggert
4627 Release code96h - 1996-06-05 08:02:21 -0400
4629 fix for handling transitions specified in Universal Time
4631 Some "public domain" notices have also been added.
4634 Release code96g - 1996-05-16 14:00:26 -0400
4636 fix for the simultaneous-DST-and-zone-change challenge
4639 Release data96h - 1996-05-09 17:40:51 -0400
4641 changes by Paul Eggert
4644 Release code96f-data96g - 1996-05-03 03:09:59 -0000
4645 [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
4647 The changes get us some of the way to fixing the problems noted in Paul
4648 Eggert's letter yesterday (in addition to a few others). The approach
4649 has been to make zic a bit smarter about figuring out what time zone
4650 abbreviations apply just after the time specified in the "UNTIL" part
4651 of a zone line. Putting the smarts in zic means avoiding having
4652 transition times show up in both "Zone" lines and "Rule" lines, which
4653 in turn avoids multiple transition time entries in time zone files.
4654 (This also makes the zic input files such as "europe" a bit shorter and
4655 should ease maintenance.)
4658 Release data96f - 1996-04-19 19:20:03 -0000
4659 [tzdata96f.tar.gz is missing!]
4661 The only changes are to the "northamerica" file; the time zone
4662 abbreviation for Denver is corrected to MST (and MDT), and the
4663 comments for Mexico have been updated.
4666 Release data96e - 1996-03-19 17:37:26 -0500
4668 Proposals by Paul Eggert, in particular the Portugal change that
4669 comes into play at the end of this month.
4672 Release data96d - 1996-03-18 20:49:39 -0500
4677 Release code96e - 1996-02-29 15:43:27 -0000
4678 [tzcode96e.tar.gz is missing!]
4680 internationalization changes and the fix to the documentation for strftime
4683 Release code96d-data96c - 1996-02-12 11:05:27 -0500
4685 The "code" file simply updates Bob Kridle's electronic address.
4687 The "data" file updates rules for Mexico.
4690 Release data96b - 1996-01-27 15:44:42 -0500
4695 Release code96c - 1996-01-16 16:58:15 -0500
4697 leap-year streamlining and binary-search changes
4702 Release code96b - 1996-01-10 20:42:39 -0500
4704 fixes and enhancements from Paul Eggert, including code that
4705 emulates the behavior of recent versions of the SunOS "date"
4709 Release 96a - 1996-01-06 09:08:24 -0500
4713 fixes to strftime.c for correct ISO 8601 week number generation,
4714 plus support for two new formats ('G' and 'g') to give ISO 8601 year
4715 numbers (which are not necessarily the same as calendar year numbers)
4718 Release code95i-data95m - 1995-12-21 12:46:47 -0500
4720 The latest revisions from Paul Eggert are included, the usno1995
4721 file has been updated, and a new file ("WWW") covering useful URLs
4725 Release code95h-data95l - 1995-12-19 18:10:12 -0500
4727 A simplification of a macro definition, a change to data for Sudan,
4728 and (for last minute shoppers) notes in the "Music" file on the CD
4732 Release code95g-data95k - 1995-10-30 10:32:47 -0500
4734 (slightly reformatted) 8-bit-clean proposed patch
4736 minor patch: US/Eastern -> America/New_York
4738 snapshot of the USNO's latest data ("usno1995")
4740 some other minor cleanups
4743 Release code95f-data95j - 1995-10-28 21:01:34 -0000
4744 [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
4748 support for 64-bit time_t's
4750 optimization in localtime.c
4753 Release code95e - 1995-10-13 13:23:57 -0400
4755 the mktime change to scan from future to past when trying to find time zone
4759 Release data95i - 1995-09-26 10:43:26 -0400
4761 For Canada/Central, guess that the Sun customer's "one week too
4762 early" was just a approximation, and the true error is one month
4763 too early. This is consistent with the rest of Canada.
4766 Release data95h - 1995-09-21 11:26:48 -0400
4768 latest changes from Paul Eggert
4771 Release code95d - 1995-09-14 11:14:45 -0400
4773 the addition of a "Music" file, which documents four recorded
4774 versions of the tune "Save That Time".
4777 Release data95g - 1995-09-01 17:21:36 -0400
4779 "yearistype" correction
4782 Release data95f - 1995-08-28 20:46:56 -0400
4784 Paul Eggert's change to the australasia file
4787 Release data95e - 1995-07-08 18:02:34 -0400
4789 The only change is a leap second at the end of this year.
4790 Thanks to Bradley White for forwarding news on the leap second.
4793 Release data95d - 1995-07-03 13:26:22 -0400
4795 Paul Eggert's changes
4798 Release data95c - 1995-07-02 19:19:28 -0400
4800 changes to "asia", "backward", "europe", and "southamerica"
4801 (read: northamericacentrics need not apply)
4804 Release code95c - 1995-03-13 14:00:46 -0500
4806 one-line fix for sign extension problems in detzcode
4809 Release 95b - 1995-03-04 11:22:38 -0500
4811 Minor changes in both:
4813 The "code" file contains a workaround for the lack of "unistd.h" in
4814 Microsoft C++ version 7.
4816 The "data" file contains a fixed "Link" for America/Shiprock.
4819 Release 94h - 1994-12-10 12:51:14 -0500
4823 * incorporate the changes to "zdump" and "date" to make changes to
4824 the "TZ" environment variable permanent;
4826 * incorporate the table changes by Paul Eggert;
4828 * include (and document) support for universal time specifications in
4829 data files - but do not (yet) include use of this feature in the
4832 Think of this as "TZ Classic" - the software has been set up not to break if
4833 universal time shows up in its input, and data entries have been
4834 left as is so as not to break existing implementations.
4837 Release data94f - 1994-08-20 12:56:09 -0400
4839 (with thanks!) the latest data updates from Paul Eggert
4842 Release data94e - 1994-06-04 13:13:53 -0400
4847 Release code94g - 1994-05-05 12:14:07 -0400
4849 fix missing "optind.c" and a reference to it in the Makefile
4852 Release code94f - 1994-05-05 13:00:33 -0000
4853 [tzcode94f.tar.gz is missing!]
4855 changes to avoid overflow in difftime, as well as changes to cope
4856 with the 52/53 challenge in strftime
4859 Release code94e - 1994-03-30 23:32:59 -0500
4861 change for the benefit of PCTS
4864 Release 94d - 1994-02-24 15:42:25 -0500
4866 Avoid clashes with POSIX semantics for zones such as GMT+4.
4868 Some other very minor housekeeping is also present.
4871 Release code94c - 1994-02-10 08:52:40 -0500
4873 Fix bug where mkdirs was broken unless you compile with
4874 -fwritable-strings (which is generally losing to do).
4877 Release 94b - 1994-02-07 10:04:33 -0500
4879 work by Paul Eggert who notes:
4881 I found another book of time zone histories by E W Whitman; it's not
4882 as extensive as Shanks but has a few goodies of its own. I used it
4883 to update the tables. I also fixed some more as a result of
4884 correspondence with Adam David and Peter Ilieve, and move some stray
4885 links from 'europe' to 'backward'. I corrected some scanning errors
4888 As far as the code goes, I fixed zic to allow years in the range
4889 INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
4890 And I cleaned up the zic documentation a little bit.
4893 Release data94a - 1994-02-03 08:58:54 -0500
4895 It simply incorporates the recently announced leap second into the
4899 Release 93g - 1993-11-22 17:28:27 -0500
4901 Paul Eggert has provided a good deal of historic information (based
4902 on Shanks), and there are some code changes to deal with the buglets
4903 that crawled out in dealing with the new information.
4906 Release 93f - 1993-10-15 12:27:46 -0400
4908 Paul Eggert's changes
4911 Release 93e - 1993-09-05 21:21:44 -0400
4913 This has updated data for Israel, England, and Kwajalein. There's
4914 also an update to "zdump" to cope with Kwajalein's 24-hour jump.
4915 Thanks to Paul Eggert and Peter Ilieve for the changes.
4918 Release 93d - 1993-06-17 23:34:17 -0400
4920 new fix and new data on Israel
4923 Release 93c - 1993-06-06 19:31:55 -0400
4928 Release 93b - 1993-02-02 14:53:58 -0500
4930 updated "leapseconds" file
4933 Release 93 - 1993-01-08 07:01:06 -0500
4935 At kre's suggestion, the package has been split in two - a code piece
4936 (which also includes documentation) that's only of use to folks who
4937 want to recompile things and a data piece useful to anyone who can
4940 The new version has a few changes to the data files, a few
4941 portability changes, and an off-by-one fix (with thanks to
4942 Tom Karzes at deshaw.com for providing a description and a
4946 Release 92c - 1992-11-21 17:35:36 -0000
4947 [tz92c.tar.Z is missing!]
4949 The fallout from the latest round of DST transitions.
4951 There are changes for Portugal, Saskatchewan, and "Pacific-New";
4952 there's also a change to "zic.c" that makes it portable to more systems.
4955 Release 92 - 1992-04-25 18:17:03 -0000
4956 [tz92.tar.Z is missing!]
4958 By popular demand (well, at any rate, following a request by kre at munnari)
4961 The 1989 update of the time zone package featured:
4963 * POSIXization (including interpretation of POSIX-style TZ environment
4964 variables, provided by Guy Harris),
4965 * ANSIfication (including versions of "mktime" and "difftime"),
4966 * SVIDulation (an "altzone" variable)
4967 * MACHination (the "gtime" function)
4968 * corrections to some time zone data (including corrections to the rules
4969 for Great Britain and New Zealand)
4970 * reference data from the United States Naval Observatory for folks who
4971 want to do additional time zones
4972 * and the 1989 data for Saudi Arabia.
4974 (Since this code will be treated as "part of the implementation" in some
4975 places and as "part of the application" in others, there's no good way to
4976 name functions, such as timegm, that are not part of the proposed ANSI C
4977 standard; such functions have kept their old, underscore-free names in this
4980 And the "dysize" function has disappeared; it was present to allow
4981 compilation of the "date" command on old BSD systems, and a version of "date"
4982 is now provided in the package. The "date" command is not created when you
4983 "make all" since it may lack options provided by the version distributed with
4984 your operating system, or may not interact with the system in the same way
4985 the native version does.
4987 Since POSIX frowns on correct leap second handling, the default behavior of
4988 the "zic" command (in the absence of a "-L" option) has been changed to omit
4989 leap second information from its output files.
4995 This file contains copies of the part of each release announcement
4996 that talks about the changes in that release. The text has been
4997 adapted and reformatted for the purposes of this file.
4999 Traditionally a release R consists of a pair of tarball files,
5000 tzcodeR.tar.gz and tzdataR.tar.gz. However, some releases (e.g.,
5001 code2010a, data2012c) consist of just one or the other tarball, and a
5002 few (e.g., code2012c-data2012d) have tarballs with mixed version
5003 numbers. Recent releases also come in an experimental format
5004 consisting of a single tarball tzdb-R.tar.lz with extra data.
5006 Release timestamps are taken from the release's commit (for newer,
5007 Git-based releases), from the newest file in the tarball (for older
5008 releases, where this info is available) or from the email announcing
5009 the release (if all else fails; these are marked with a time zone
5010 abbreviation of -0000 and an "is missing!" comment).
5012 Earlier versions of the code and data were not announced on the tz
5013 list and are not summarized here.
5015 This file is in the public domain.