1 News for the tz database
3 Release 2019b - 2019-07-01 00:09:53 -0700
6 Brazil no longer observes DST.
7 'zic -b slim' outputs smaller TZif files; please try it out.
8 Palestine's 2019 spring-forward transition was on 03-29, not 03-30.
10 Changes to future timestamps
12 Brazil has canceled DST and will stay on standard time indefinitely.
13 (Thanks to Steffen Thorsen, Marcus Diniz, and Daniel Soares de
16 Predictions for Morocco now go through 2087 instead of 2037, to
17 work around a problem on newlib when using TZif files output by
18 zic 2019a or earlier. (Problem reported by David Gauchard.)
20 Changes to past and future timestamps
22 Palestine's 2019 spring transition was 03-29 at 00:00, not 03-30
23 at 01:00. (Thanks to Sharef Mustafa and Even Scharning.) Guess
24 future transitions to be March's last Friday at 00:00.
26 Changes to past timestamps
28 Hong Kong's 1941-06-15 spring-forward transition was at 03:00, not
29 03:30. Its 1945 transition from JST to HKT was on 11-18 at 02:00,
30 not 09-15 at 00:00. In 1946 its spring-forward transition was on
31 04-21 at 00:00, not the previous day at 03:30. From 1946 through
32 1952 its fall-back transitions occurred at 04:30, not at 03:30.
33 In 1947 its fall-back transition was on 11-30, not 12-30.
36 Changes to past time zone abbreviations
38 Italy's 1866 transition to Rome Mean Time was on December 12, not
39 September 22. This affects only the time zone abbreviation for
40 Europe/Rome between those dates. (Thanks to Stephen Trainor and
43 Changes affecting metadata only
45 Add info about the Crimea situation in zone1970.tab and zone.tab.
46 (Problem reported by Serhii Demediuk.)
50 zic's new -b option supports a way to control data bloat and to
51 test for year-2038 bugs in software that reads TZif files.
52 'zic -b fat' and 'zic -b slim' generate larger and smaller output;
53 for example, changing from fat to slim shrinks the Europe/London
54 file from 3648 to 1599 bytes, saving about 56%. Fat and slim
55 files represent the same set of timestamps and use the same TZif
56 format as documented in tzfile(5) and in Internet RFC 8536.
57 Fat format attempts to work around bugs or incompatibilities in
58 older software, notably software that mishandles 64-bit TZif data
59 or uses obsolete TZ strings like "EET-2EEST" that lack DST rules.
60 Slim format is more efficient and does not work around 64-bit bugs
61 or obsolete TZ strings. Currently zic defaults to fat format
62 unless you compile with -DZIC_BLOAT_DEFAULT=\"slim\"; this
63 out-of-the-box default is intended to change in future releases
64 as the buggy software often mishandles timestamps anyway.
66 zic no longer treats a set of rules ending in 2037 specially.
67 Previously, zic assumed that such a ruleset meant that future
68 timestamps could not be predicted, and therefore omitted a
69 POSIX-like TZ string in the TZif output. The old behavior is no
70 longer needed for current tzdata, and caused problems with newlib
71 when used with older tzdata (reported by David Gauchard).
73 zic no longer generates some artifact transitions. For example,
74 Europe/London no longer has a no-op transition in January 1996.
76 Changes to build procedure
78 tzdata.zi now assumes zic 2017c or later. This shrinks tzdata.zi
81 Changes to documentation and commentary
83 The Makefile now documents the POSIXRULES macro as being obsolete,
84 and similarly, zic's -p POSIXRULES option is now documented as
85 being obsolete. Although the POSIXRULES feature still exists and
86 works as before, in practice it is rarely used for its intended
87 purpose, and it does not work either in the default reference
88 implementation (for timestamps after 2037) or in common
89 implementations such as GNU/Linux (for contemporary timestamps).
90 Since POSIXRULES was designed primarily as a temporary transition
91 facility for System V platforms that died off decades ago, it is
92 being decommissioned rather than institutionalized.
94 New info on Bonin Islands and Marcus (thanks to Wakaba and Phake Nick).
97 Release 2019a - 2019-03-25 22:01:33 -0700
100 Palestine "springs forward" on 2019-03-30 instead of 2019-03-23.
101 Metlakatla "fell back" to rejoin Alaska Time on 2019-01-20 at 02:00.
103 Changes to past and future timestamps
105 Palestine will not start DST until 2019-03-30, instead of 2019-03-23 as
106 previously predicted. Adjust our prediction by guessing that spring
107 transitions will be between 24 and 30 March, which matches recent practice
108 since 2016. (Thanks to Even Scharning and Tim Parenti.)
110 Metlakatla ended its observance of Pacific standard time,
111 rejoining Alaska Time, on 2019-01-20 at 02:00. (Thanks to Ryan
112 Stanley and Tim Parenti.)
114 Changes to past timestamps
116 Israel observed DST in 1980 (08-02/09-13) and 1984 (05-05/08-25).
117 (Thanks to Alois Treindl and Isaac Starkman.)
119 Changes to time zone abbreviations
121 Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
122 of being a separate zone that generates the abbreviation "UCT",
123 which nowadays is typically a typo. (Problem reported by Isiah
128 zic now has an -r option to limit the time range of output data.
129 For example, 'zic -r @1000000000' limits the output data to
130 timestamps starting 1000000000 seconds after the Epoch.
131 This helps shrink output size and can be useful for applications
132 not needing the full timestamp history, such as TZDIST truncation;
133 see Internet RFC 8536 section 5.1. (Inspired by a feature request
134 from Christopher Wong, helped along by bug reports from Wong and
137 Changes to documentation
139 Mention Internet RFC 8536 (February 2019), which documents TZif.
141 tz-link.html now cites tzdata-meta
142 <https://tzdata-meta.timtimeonline.com/>.
145 Release 2018i - 2018-12-30 11:05:43 -0800
148 São Tomé and Príncipe switches from +01 to +00 on 2019-01-01.
150 Changes to future timestamps
152 Due to a change in government, São Tomé and Príncipe switches back
153 from +01 to +00 on 2019-01-01 at 02:00. (Thanks to Vadim
154 Nasardinov and Michael Deckers.)
157 Release 2018h - 2018-12-23 17:59:32 -0800
160 Qyzylorda, Kazakhstan moved from +06 to +05 on 2018-12-21.
161 New zone Asia/Qostanay because Qostanay, Kazakhstan didn't move.
162 Metlakatla, Alaska observes PST this winter only.
163 Guess Morocco will continue to adjust clocks around Ramadan.
164 Add predictions for Iran from 2038 through 2090.
166 Changes to future timestamps
168 Guess that Morocco will continue to fall back just before and
169 spring forward just after Ramadan, the practice since 2012.
170 (Thanks to Maamar Abdelkader.) This means Morocco will observe
171 negative DST during Ramadan in main and vanguard formats, and in
172 rearguard format it stays in the +00 timezone and observes
173 ordinary DST in all months other than Ramadan. As before, extend
174 this guesswork to the year 2037. As a consequence, Morocco is
175 scheduled to observe three DST transitions in some Gregorian years
176 (e.g., 2033) due to the mismatch between the Gregorian and Islamic
179 The table of exact transitions for Iranian DST has been extended.
180 It formerly cut off before the year 2038 in a nod to 32-bit time_t.
181 It now cuts off before 2091 as there is doubt about how the Persian
182 calendar will treat 2091. This change predicts DST transitions in
183 2038-9, 2042-3, and 2046-7 to occur one day later than previously
184 predicted. As before, post-cutoff transitions are approximated.
186 Changes to past and future timestamps
188 Qyzylorda (aka Kyzylorda) oblast in Kazakhstan moved from +06 to
189 +05 on 2018-12-21. This is a zone split as Qostanay (aka
190 Kostanay) did not switch, so create a zone Asia/Qostanay.
192 Metlakatla moved from Alaska to Pacific standard time on 2018-11-04.
193 It did not change clocks that day and remains on -08 this winter.
194 (Thanks to Ryan Stanley.) It will revert to the usual Alaska
195 rules next spring, so this change affects only timestamps
196 from 2018-11-04 through 2019-03-10.
198 Change to past timestamps
200 Kwajalein's 1993-08-20 transition from -12 to +12 was at 24:00,
201 not 00:00. I transcribed the time incorrectly from Shanks.
202 (Thanks to Phake Nick.)
204 Nauru's 1979 transition was on 02-10 at 02:00, not 05-01 at 00:00.
205 (Thanks to Phake Nick.)
207 Guam observed DST irregularly from 1959 through 1977.
208 (Thanks to Phake Nick.)
210 Hong Kong observed DST in 1941 starting 06-15 (not 04-01), then on
211 10-01 changed standard time to +08:30 (not +08). Its transition
212 back to +08 after WWII was on 1945-09-15, not the previous day.
213 Its 1904-10-30 change took effect at 01:00 +08 (not 00:00 LMT).
214 (Thanks to Phake Nick, Steve Allen, and Joseph Myers.) Also,
215 its 1952 fallback was on 11-02 (not 10-25).
217 This release contains many changes to timestamps before 1946 due
218 to Japanese possession or occupation of Pacific/Chuuk,
219 Pacific/Guam, Pacific/Kosrae, Pacific/Kwajalein, Pacific/Majuro,
220 Pacific/Nauru, Pacific/Palau, and Pacific/Pohnpei.
221 (Thanks to Phake Nick.)
223 Assume that the Spanish East Indies was like the Philippines and
224 observed American time until the end of 1844. This affects
225 Pacific/Chuuk, Pacific/Kosrae, Pacific/Palau, and Pacific/Pohnpei.
227 Changes to past tm_isdst flags
229 For the recent Morocco change, the tm_isdst flag should be 1 from
230 2018-10-27 00:00 to 2018-10-28 03:00. (Thanks to Michael Deckers.)
231 Give a URL to the official decree. (Thanks to Matt Johnson.)
234 Release 2018g - 2018-10-26 22:22:45 -0700
237 Morocco switches to permanent +01 on 2018-10-28.
239 Changes to future timestamps
241 Morocco switches from +00/+01 to permanent +01 effective 2018-10-28,
242 so its clocks will not fall back as previously scheduled.
243 (Thanks to Mohamed Essedik Najd and Brian Inglis.)
247 When generating TZif files with leap seconds, zic no longer uses a
248 format that trips up older 32-bit clients, fixing a bug introduced
249 in 2018f. (Reported by Daniel Fischer.) Also, the zic workaround
250 for QTBUG-53071 now also works for TZif files with leap seconds.
252 The translator to rearguard format now rewrites the line
253 "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
254 "Rule Japan 1948 1951 - Sep Sun>=9 1:00 0 S".
255 This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
256 and earlier. (Reported by Christos Zoulas.)
258 Changes to past time zone abbreviations
260 Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
261 This reverts to 2011h, as the abbreviation change in 2011i was
264 Changes to documentation
266 tzfile.5 has new sections on interoperability issues.
269 Release 2018f - 2018-10-18 00:14:18 -0700
272 Volgograd moves from +03 to +04 on 2018-10-28.
273 Fiji ends DST 2019-01-13, not 2019-01-20.
274 Most of Chile changes DST dates, effective 2019-04-06.
276 Changes to future timestamps
278 Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
279 (Thanks to Alexander Fetisov and Stepan Golosunov.)
281 Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
282 predicted. (Thanks to Raymond Kumar.) Adjust future predictions
285 Most of Chile will end DST on the first Saturday in April at 24:00 mainland
286 time, and resume DST on the first Saturday in September at 24:00 mainland
287 time. The changes are effective from 2019-04-06, and do not affect the
288 Magallanes region modeled by America/Punta_Arenas. (Thanks to Juan Correa
289 and Tim Parenti.) Adjust future predictions accordingly.
291 Changes to past timestamps
293 The 2018-05-05 North Korea 30-minute time zone change took place
294 at 23:30 the previous day, not at 00:00 that day.
296 China's 1988 spring-forward transition was on April 17, not
297 April 10. Its DST transitions in 1986/91 were at 02:00, not 00:00.
300 Fix several issues for Macau before 1992. Macau's pre-1904 LMT
301 was off by 10 s. Macau switched to +08 in 1904 not 1912, and
302 temporarily switched to +09/+10 during World War II. Macau
303 observed DST in 1942/79, not 1961/80, and there were several
304 errors for transition times and dates. (Thanks to P Chan.)
306 The 1948-1951 fallback transitions in Japan were at 25:00 on
307 September's second Saturday, not at 24:00. (Thanks to Phake Nick.)
308 zic turns this into 01:00 on the day after September's second
309 Saturday, which is the best that POSIX or C platforms can do.
311 Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
312 paper by Li Yu, replacing more-questionable data from Shanks.
314 Changes to time zone abbreviations
316 Use "PST" and "PDT" for Philippine time. (Thanks to Paul Goyette.)
320 zic now always generates TZif files where time type 0 is used for
321 timestamps before the first transition. This simplifies the
322 reading of TZif files and should not affect behavior of existing
323 TZif readers because the same set of time types is used; only
324 their internal indexes may have changed. This affects only the
325 legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
326 EET, which previously used nonzero types for these timestamps.
328 Because of the type 0 change, zic no longer outputs a dummy
329 transition at time -2**59 (before the Big Bang), as clients should
330 no longer need this to handle historical timestamps correctly.
331 This reverts a change introduced in 2013d and shrinks most TZif
332 files by a few bytes.
334 zic now supports negative time-of-day in Rule and Leap lines, e.g.,
335 "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
336 occurs at 18:00 on the Saturday before the last Sunday in April.
337 This behavior was documented in 2018a but the code did not
338 entirely match the documentation.
340 localtime.c no longer requires at least one time type in TZif
341 files that lack transitions or have a POSIX-style TZ string. This
342 future-proofs the code against possible future extensions to the
343 format that would allow TZif files with POSIX-style TZ strings and
344 without transitions or time types.
346 A read-access subscript error in localtime.c has been fixed.
347 It could occur only in TZif files with timecnt == 0, something that
348 does not happen in practice now but could happen in future versions.
350 localtime.c no longer ignores TZif POSIX-style TZ strings that
351 specify only standard time. Instead, these TZ strings now
352 override the default time type for timestamps after the last
353 transition (or for all timestamps if there are no transitions),
354 just as DST strings specifying DST have always done.
356 leapseconds.awk now outputs "#updated" and "#expires" comments,
357 and supports leap seconds at the ends of months other than June
358 and December. (Inspired by suggestions from Chris Woodbury.)
360 Changes to documentation
362 New restrictions: A Rule name must start with a character that
363 is neither an ASCII digit nor "-" nor "+", and an unquoted name
364 should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
365 The latter restriction makes room for future extensions (a
366 possibility noted by Tom Lane).
368 tzfile.5 now documents what time types apply before the first and
369 after the last transition, if any.
371 Documentation now uses the spelling "timezone" for a TZ setting
372 that determines timestamp history, and "time zone" for a
373 geographic region currently sharing the same standard time.
375 The name "TZif" is now used for the tz binary data format.
377 tz-link.htm now mentions the A0 TimeZone Migration utilities.
378 (Thanks to Aldrin Martoq for the link.)
380 Changes to build procedure
382 New 'make' target 'rearguard_tarballs' to build the rearguard
383 tarball only. This is a convenience on platforms that lack lzip
384 if you want to build the rearguard tarball. (Problem reported by
387 tzdata.zi is now more stable from release to release. (Problem
388 noted by Tom Lane.) It is also a bit shorter.
390 tzdata.zi now can contain comment lines documenting configuration
391 information, such as which data format was selected, which input
392 files were used, and how leap seconds are treated. (Problems
393 noted by Lester Caine and Brian Inglis.) If the Makefile defaults
394 are used these comment lines are absent, for backward
395 compatibility. A redistributor intending to alter its copy of the
396 files should also append "-LABEL" to the 'version' file's first
397 line, where "LABEL" identifies the redistributor's change.
400 Release 2018e - 2018-05-01 23:42:51 -0700
404 North Korea switches back to +09 on 2018-05-05.
405 The main format uses negative DST again, for Ireland etc.
406 'make tarballs' now also builds a rearguard tarball.
407 New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
409 Changes to past and future timestamps
411 North Korea switches back from +0830 to +09 on 2018-05-05.
412 (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
415 Bring back the negative-DST changes of 2018a, except be more
416 compatible with data parsers that do not support negative DST.
417 Also, this now affects historical timestamps in Namibia and the
418 former Czechoslovakia, not just Ireland. The main format now uses
419 negative DST to model timestamps in Europe/Dublin (from 1971 on),
420 Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This
421 does not affect UT offsets, only time zone abbreviations and the
422 tm_isdst flag. Also, this does not affect rearguard or vanguard
423 formats; effectively the main format now uses vanguard instead of
424 rearguard format. Data parsers that do not support negative DST
425 can still use data from the rearguard tarball described below.
427 Changes to build procedure
429 The command 'make tarballs' now also builds the tarball
430 tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
431 except that it uses rearguard format intended for trailing-edge
434 Changes to data format and to code
436 The SAVE column of Rule and Zone lines can now have an 's' or 'd'
437 suffix, which specifies whether the adjusted time is standard time
438 or daylight saving time. If no suffix is given, daylight saving
439 time is used if and only if the SAVE column is nonzero; this is
440 the longstanding behavior. Although this new feature is not used
441 in tzdata, it could be used to specify the legal time in Namibia
442 1994-2017, as opposed to the popular time (see below).
444 Changes to past timestamps
446 From 1994 through 2017 Namibia observed DST in winter, not summer.
447 That is, it used negative DST, as Ireland still does. This change
448 does not affect UTC offsets; it affects only the tm_isdst flag and
449 the abbreviation used during summer, which is now CAT, not WAST.
450 Although (as noted by Michael Deckers) summer and winter time were
451 both simply called "standard time" in Namibian law, in common
452 practice winter time was considered to be DST (as noted by Stephen
453 Colebourne). The full effect of this change is only in vanguard
454 and main format; in rearguard format, the tm_isdst flag is still
455 zero in winter and nonzero in summer.
457 In 1946/7 Czechoslovakia also observed negative DST in winter.
458 The full effect of this change is only in vanguard and main
459 formats; in rearguard format, it is modeled as plain GMT without
460 daylight saving. Also, the dates of some 1944/5 DST transitions
461 in Czechoslovakia have been changed.
464 Release 2018d - 2018-03-22 07:05:46 -0700
468 Palestine starts DST a week earlier in 2018.
469 Add support for vanguard and rearguard data consumers.
470 Add subsecond precision to source data format, though not to data.
472 Changes to future timestamps
474 In 2018, Palestine starts DST on March 24, not March 31.
475 Adjust future predictions accordingly. (Thanks to Sharef Mustafa.)
477 Changes to past and future timestamps
479 Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
480 at 04:00. (Thanks to Steffen Thorsen.)
482 Changes to past timestamps
484 Historical transitions for Uruguay, represented by
485 America/Montevideo, have been updated per official legal documents,
486 replacing previous data mainly originating from the inventions of
487 Shanks & Pottenger. This has resulted in adjustments ranging from
488 30 to 90 minutes in either direction over at least two dozen
489 distinct periods ranging from one day to several years in length.
490 A mere handful of pre-1991 transitions are unaffected; data since
491 then has come from more reliable contemporaneous reporting. These
492 changes affect various timestamps in 1920-1923, 1936, 1939,
493 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
494 Additionally, Uruguay's pre-standard-time UT offset has been
495 adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
496 match the location of the Observatory of the National Meteorological
497 Institute in Montevideo.
498 (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
500 Enderbury and Kiritimati skipped New Year's Eve 1994, not
501 New Year's Day 1995. (Thanks to Kerry Shetline.)
503 Fix the 1912-01-01 transition for Portugal and its colonies.
504 This transition was at 00:00 according to the new UT offset, not
505 according to the old one. Also assume that Cape Verde switched on
506 the same date as the rest, not in 1907. This affects
507 Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
508 Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
509 (Thanks to Michael Deckers.)
511 Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
514 Changes to past time zone abbreviations
516 MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There
517 is no clock change associated with the transition.
519 Changes to build procedure
521 The new DATAFORM macro in the Makefile lets the installer choose
522 among three source data formats. The idea is to lessen downstream
523 disruption when data formats are improved.
525 * DATAFORM=vanguard installs from the latest, bleeding-edge
526 format. DATAFORM=main (the default) installs from the format
527 used in the 'africa' etc. files. DATAFORM=rearguard installs
528 from a trailing-edge format. Eventually, elements of today's
529 vanguard format should move to the main format, and similarly
530 the main format's features should eventually move to the
533 * In the current version, the main and rearguard formats are
534 identical and match that of 2018c, so this change does not
535 affect default behavior. The vanguard format currently contains
536 one feature not in the main format: negative SAVE values. This
537 improves support for Ireland, which uses Irish Standard Time
538 (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has
539 supported negative SAVE values for decades, and this feature
540 should move to the main format soon. However, it will not move
541 to the rearguard format for quite some time because some
542 downstream parsers do not support it.
544 * The build procedure constructs three files vanguard.zi, main.zi,
545 and rearguard.zi, one for each format. Although the files
546 represent essentially the same data, they may have minor
547 discrepancies that users are not likely to notice. The files
548 are intended for downstream data consumers and are not
549 installed. Zoneinfo parsers that do not support negative SAVE values
550 should start using rearguard.zi, so that they will be unaffected
551 when the negative-DST feature moves from vanguard to main.
552 Bleeding-edge Zoneinfo parsers that support the new features
553 already can use vanguard.zi; in this respect, current tzcode is
556 The Makefile should now be safe for parallelized builds, and 'make
557 -j to2050new.tzs' is now much faster on a multiprocessor host
560 When built with -DSUPPRESS_TZDIR, the tzcode library no longer
561 prepends TZDIR/ to file names that do not begin with '/'. This is
562 not recommended for general use, due to its security implications.
563 (From a suggestion by Manuela Friedrich.)
567 zic now accepts subsecond precision in expressions like
568 00:19:32.13, which is approximately the legal time of the
569 Netherlands from 1835 to 1937. However, because it is
570 questionable whether the few recorded uses of non-integer offsets
571 had subsecond precision in practice, there are no plans for tzdata
572 to use this feature. (Thanks to Steve Allen for pointing out
573 the limitations of historical data in this area.)
575 The code is a bit more portable to MS-Windows. Installers can
576 compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
577 reserve identifiers like 'localtime'. (Thanks to Manuela
580 Changes to documentation and commentary
582 theory.html now outlines tzdb's extensions to POSIX's model for
583 civil time, and has a section "POSIX features no longer needed"
584 that lists POSIX API components that are now vestigial.
585 (From suggestions by Steve Summit.) It also better distinguishes
586 time zones from tz regions. (From a suggestion by Guy Harris.)
588 Commentary is now more consistent about using the phrase "daylight
589 saving time", to match the C name tm_isdst. Daylight saving time
590 need not occur in summer, and need not have a positive offset from
593 Commentary about historical transitions in Uruguay has been expanded
594 with links to many relevant legal documents.
595 (Thanks to Tim Parenti.)
597 Commentary now uses some non-ASCII characters with Unicode value
598 less than U+0100, as they can be useful and should work even with
599 older editors such as XEmacs.
602 Release 2018c - 2018-01-22 23:00:44 -0800
605 Revert Irish changes that relied on negative SAVE values.
609 Revert the 2018a change to Europe/Dublin. As before, this change
610 does not affect UT offsets or abbreviations; it affects only
611 whether timestamps are considered to be standard time or
612 daylight-saving time, as expressed in the tm_isdst flag of C's
613 struct tm type. This reversion is intended to be a temporary
614 workaround for problems discovered with downstream uses of
615 releases 2018a and 2018b, which implemented Irish time by using
616 negative SAVE values in the Eire rules of the 'europe' file.
617 Although negative SAVE values have been part of tzcode for many
618 years and are supported by many platforms, they were not
619 documented before 2018a and ICU and OpenJDK do not currently
620 support them. A mechanism to export data to platforms lacking
621 support for negative DST is planned to be developed before the
622 change is reapplied. (Problems reported by Deborah Goldsmith and
625 Changes to past timestamps
627 Japanese DST transitions (1948-1951) were Sundays at 00:00, not
628 Saturdays or Sundays at 02:00. (Thanks to Takayuki Nikai.)
630 Changes to build procedure
632 The build procedure now works around mawk 1.3.3's lack of support
633 for character class expressions. (Problem reported by Ohyama.)
636 Release 2018b - 2018-01-17 23:24:48 -0800
639 Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
641 Changes to build procedure
643 The distribution now contains the file 'pacificnew' again.
644 This file was inadvertantly omitted in the 2018a distribution.
645 (Problem reported by Matias Fonzo.)
648 Release 2018a - 2018-01-12 22:29:21 -0800
651 São Tomé and Príncipe switched from +00 to +01.
652 Brazil's DST will now start on November's first Sunday.
653 Ireland's standard time is now in the summer, not the winter.
654 Use Debian-style installation locations, instead of 4.3BSD-style.
657 Changes to past and future timestamps
659 São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
660 01:00. (Thanks to Steffen Thorsen and Michael Deckers.)
662 Changes to future timestamps
664 Starting in 2018 southern Brazil will begin DST on November's
665 first Sunday instead of October's third Sunday. (Thanks to
668 Changes to past timestamps
670 A discrepancy of 4 s in timestamps before 1931 in South Sudan has
671 been corrected. The 'backzone' and 'zone.tab' files did not agree
672 with the 'africa' and 'zone1970.tab' files. (Problem reported by
675 The abbreviation invented for Bolivia Summer Time (1931-2) is now
676 BST instead of BOST, to be more consistent with the convention
677 used for Latvian Summer Time (1918-9) and for British Summer Time.
681 Change Europe/Dublin so that it observes Irish Standard Time (UT
682 +01) in summer and GMT (as negative daylight-saving) in winter,
683 instead of observing standard time (GMT) in winter and Irish
684 Summer Time (UT +01) in summer. This change does not affect UT
685 offsets or abbreviations; it affects only whether timestamps are
686 considered to be standard time or daylight-saving time, as
687 expressed in the tm_isdst flag of C's struct tm type.
688 (Discrepancy noted by Derick Rethans.)
690 Changes to build procedure
692 The default installation locations have been changed to mostly
693 match Debian circa 2017, instead of being designed as an add-on to
694 4.3BSD circa 1986. This affects the Makefile macros TOPDIR,
695 TZDIR, MANDIR, and LIBDIR. New Makefile macros TZDEFAULT, USRDIR,
696 USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
697 locations more precisely. (This responds to suggestions from
698 Brian Inglis and from Steve Summit.)
700 The default installation procedure no longer creates the
701 backward-compatibility link US/Pacific-New, which causes
702 confusion during user setup (e.g., see Debian bug 815200).
703 Use 'make BACKWARD="backward pacificnew"' to create the link
704 anyway, for now. Eventually we plan to remove the link entirely.
706 tzdata.zi now contains a version-number comment.
707 (Suggested by Tom Lane.)
709 The Makefile now quotes values like BACKWARD more carefully when
710 passing them to the shell. (Problem reported by Zefram.)
712 Builders no longer need to specify -DHAVE_SNPRINTF on platforms
713 that have snprintf and use pre-C99 compilers. (Problem reported
718 zic has a new option -t FILE that specifies the location of the
719 file that determines local time when TZ is unset. The default for
720 this location can be configured via the new TZDEFAULT makefile
721 macro, which defaults to /etc/localtime.
723 Diagnostics and commentary now distinguish UT from UTC more
724 carefully; see theory.html for more information about UT vs UTC.
726 zic has been ported to GCC 8's -Wstringop-truncation option.
727 (Problem reported by Martin Sebor.)
729 Changes to documentation and commentary
731 The zic man page now documents the longstanding behavior that
732 times and years can be out of the usual range, with negative times
733 counting backwards from midnight and with year 0 preceding year 1.
734 (Problem reported by Michael Deckers.)
736 The theory.html file now mentions the POSIX limit of six chars
737 per abbreviation, and lists alphabetic abbreviations used.
739 The files tz-art.htm and tz-link.htm have been renamed to
740 tz-art.html and tz-link.html, respectively, for consistency with
741 other file names and to simplify web server configuration.
744 Release 2017c - 2017-10-20 14:49:34 -0700
747 Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
748 Fiji ends DST 2018-01-14, not 2018-01-21.
749 Namibia switches from +01/+02 to +02 on 2018-04-01.
750 Sudan switches from +03 to +02 on 2017-11-01.
751 Tonga likely switches from +13/+14 to +13 on 2017-11-05.
752 Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
753 A new file tzdata.zi now holds a small text copy of all data.
754 The zic input format has been regularized slightly.
756 Changes to future timestamps
758 Northern Cyprus has decided to resume EU rules starting
759 2017-10-29, thus reinstituting winter time.
761 Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
762 predicted. (Thanks to Dominic Fok.) Adjust future predictions
765 Namibia will switch from +01 with DST to +02 all year on
766 2017-09-03 at 02:00. This affects UT offsets starting 2018-04-01
767 at 02:00. (Thanks to Steffen Thorsen.)
769 Sudan will switch from +03 to +02 on 2017-11-01. (Thanks to Ahmed
770 Atyya and Yahia Abdalla.) South Sudan is not switching, so
771 Africa/Juba is no longer a link to Africa/Khartoum.
773 Tonga has likely ended its experiment with DST, and will not
774 adjust its clocks on 2017-11-05. Although Tonga has not announced
775 whether it will continue to observe DST, the IATA is assuming that
776 it will not. (Thanks to David Wade.)
778 Turks & Caicos will switch from -04 all year to -05 with US DST on
779 2018-03-11 at 03:00. This affects UT offsets starting 2018-11-04
780 at 02:00. (Thanks to Steffen Thorsen.)
782 Changes to past timestamps
784 Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
785 (Thanks to Arthur David Olson.)
787 Detroit did not observe DST in 1967.
789 Use railway time for Asia/Kolkata before 1941, by switching to
790 Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
791 1906. Also, treat 1941-2's +0630 as DST, like 1942-5.
793 Europe/Dublin's 1946 and 1947 fallback transitions occurred at
794 02:00 standard time, not 02:00 DST. (Thanks to Michael Deckers.)
796 Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
797 American time in 1892, not 1879. (Thanks to Michael Deckers.)
799 Adjust the 1867 transition in Alaska to better reflect the
800 historical record, by changing it to occur on 1867-10-18 at 15:30
801 Sitka time rather than at the start of 1867-10-17 local time.
802 Although strictly speaking this is accurate only for Sitka,
803 the rest of Alaska's blanks need to be filled in somehow.
805 Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
806 (Thanks to Michael Deckers.)
808 Add 7 s to the UT offset in Asia/Yangon before 1920.
810 Changes to zone names
812 Remove Canada/East-Saskatchewan from the 'backward' file, as it
813 exceeded the 14-character limit and was an unused misnomer anyway.
815 Changes to build procedure
817 To support applications that prefer to read time zone data in text
818 form, two zic input files tzdata.zi and leapseconds are now
819 installed by default. The commands 'zic tzdata.zi' and 'zic -L
820 leapseconds tzdata.zi' can reproduce the tzdata binary files
821 without and with leap seconds, respectively. To prevent these two
822 new files from being installed, use 'make TZDATA_TEXT=', and to
823 suppress leap seconds from the tzdata text installation, use 'make
824 TZDATA_TEXT=tzdata.zi'.
826 'make BACKWARD=' now suppresses backward-compatibility names
827 like 'US/Pacific' that are defined in the 'backward' and
830 'make check' now works on systems that lack a UTF-8 locale,
831 or that lack the nsgmls program. Set UTF8_LOCALE to configure
832 the name of a UTF-8 locale, if you have one.
834 Y2K runtime checks are no longer enabled by default. Add
835 -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
836 adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
837 to disable them. (New name suggested by Brian Inglis.)
839 The build procedure for zdump now works on AIX 7.1.
840 (Problem reported by Kees Dekker.)
844 zic and the reference runtime now reject multiple leap seconds
845 within 28 days of each other, or leap seconds before the Epoch.
846 As a result, support for double leap seconds, which was
847 obsolescent and undocumented, has been removed. Double leap
848 seconds were an error in the C89 standard; they have never existed
849 in civil timekeeping. (Thanks to Robert Elz and Bradley White for
850 noticing glitches in the code that uncovered this problem.)
852 zic now warns about use of the obsolescent and undocumented -y
853 option, and about use of the obsolescent TYPE field of Rule lines.
855 zic now allows unambiguous abbreviations like "Sa" and "Su" for
856 weekdays; formerly it rejected them due to a bug. Conversely, zic
857 no longer considers non-prefixes to be abbreviations; for example,
858 it no longer accepts "lF" as an abbreviation for "lastFriday".
859 Also, zic warns about the undocumented usage with a "last-"
860 prefix, e.g., "last-Fri".
862 Similarly, zic now accepts the unambiguous abbreviation "L" for
863 "Link" in ordinary context and for "Leap" in leap-second context.
864 Conversely, zic no longer accepts non-prefixes such as "La" as
865 abbreviations for words like "Leap".
867 zic no longer accepts leap second lines in ordinary input, or
868 ordinary lines in leap second input. Formerly, zic sometimes
869 warned about this undocumented usage and handled it incorrectly.
871 The new macro HAVE_TZNAME governs whether the tzname external
872 variable is exported, instead of USG_COMPAT. USG_COMPAT now
873 governs only the external variables "timezone" and "daylight".
874 This change is needed because the three variables are not in the
875 same category: although POSIX requires tzname, it specifies the
876 other two variables as optional. Also, USG_COMPAT is now 1 or 0:
877 if not defined, the code attempts to guess it from other macros.
879 localtime.c and difftime.c no longer require stdio.h, and .c files
880 other than zic.c no longer require sys/wait.h.
882 zdump.c no longer assumes snprintf. (Reported by Jonathan Leffler.)
884 Calculation of time_t extrema works around a bug in GCC 4.8.4
885 (Reported by Stan Shebs and Joseph Myers.)
887 zic.c no longer mistranslates formats of line numbers in non-English
888 locales. (Problem reported by Benno Schulenberg.)
890 Several minor changes have been made to the code to make it a
891 bit easier to port to MS-Windows and Solaris. (Thanks to Kees
892 Dekker for reporting the problems.)
894 Changes to documentation and commentary
896 The two new files 'theory.html' and 'calendars' contain the
897 contents of the removed file 'Theory'. The goal is to document
898 tzdb theory more accessibly.
900 The zic man page now documents abbreviation rules.
902 tz-link.htm now covers how to apply tzdata changes to clients.
903 (Thanks to Jorge Fábregas for the AIX link.) It also mentions MySQL.
905 The leap-seconds.list URL has been updated to something that is
906 more reliable for tzdb. (Thanks to Tim Parenti and Brian Inglis.)
908 Release 2017b - 2017-03-17 07:30:38 -0700
910 Briefly: Haiti has resumed DST.
912 Changes to past and future timestamps
914 Haiti resumed observance of DST in 2017. (Thanks to Steffen Thorsen.)
916 Changes to past timestamps
918 Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
920 Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
921 is one byte over the POSIX limit. (Problem reported by Derick Rethans.)
925 The reference localtime implementation now falls back on the
926 current US daylight-saving transition rules rather than the
927 1987-2006 rules. This fallback occurs only when (1) the TZ
928 environment variable has a value like "AST4ADT" that asks
929 for daylight saving time but does not specify the rules, (2) there
930 is no file by that name, and (3) the TZDEFRULES file cannot be
931 loaded. (Thanks to Tom Lane.)
934 Release 2017a - 2017-02-28 00:05:36 -0800
936 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
939 Changes to future timestamps
941 Mongolia no longer observes DST. (Thanks to Ganbold Tsagaankhuu.)
943 Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
944 Its clocks diverge from America/Santiago starting 2017-05-13 at
945 23:00, hiving off a new zone America/Punta_Arenas. Although the
946 Chilean government says this change expires in May 2019, for now
947 assume it's permanent. (Thanks to Juan Correa and Deborah
948 Goldsmith.) This also affects Antarctica/Palmer.
950 Changes to past timestamps
952 Fix many entries for historical timestamps for Europe/Madrid
953 before 1979, to agree with tables compiled by Pere Planesas of the
954 National Astronomical Observatory of Spain. As a side effect,
955 this changes some timestamps for Africa/Ceuta before 1929, which
956 are probably guesswork anyway. (Thanks to Steve Allen and
957 Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
958 correcting the 1901 transition.)
960 Ecuador observed DST from 1992-11-28 to 1993-02-05.
961 (Thanks to Alois Treindl.)
963 Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
964 (Thanks to Stepan Golosunov.)
966 Changes to past and future time zone abbreviations
968 Switch to numeric time zone abbreviations for South America, as
969 part of the ongoing project of removing invented abbreviations.
970 This avoids the need to invent an abbreviation for the new Chilean
971 new zone. Similarly, switch from invented to numeric time zone
972 abbreviations for Afghanistan, American Samoa, the Azores,
973 Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
974 Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
975 Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
976 Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
977 the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
978 Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
979 Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
980 Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
981 Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
982 Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
983 for half-hour daylight saving time in Belize before 1944 and in
984 the Dominican Republic before 1975; and for Canary Islands before
985 1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
986 Indian Summer Time before 1942, for Indonesia before around 1964,
987 for Kenya before 1960, for Liberia before 1973, for Madeira before
988 1967, for Namibia before 1943, for the Netherlands in 1937-9, for
989 Pakistan before 1971, for Western Sahara before 1977, and for
990 Zaporozhye in 1880-1924.
992 For Alaska time from 1900 through 1967, instead of "CAT" use the
993 abbreviation "AST", the abbreviation commonly used at the time
994 (Atlantic Standard Time had not been standardized yet). Use "AWT"
995 and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
997 Use "CST" and "CDT" instead of invented abbreviations for Macau
998 before 1999 and Taiwan before 1938, and use "JST" instead of the
999 invented abbreviation "JCST" for Japan and Korea before 1938.
1001 Change to database entry category
1003 Move the Pacific/Johnston link from 'australasia' to 'backward',
1004 since Johnston is now uninhabited.
1008 zic no longer mishandles some transitions in January 2038 when it
1009 attempts to work around Qt bug 53071. This fixes a bug affecting
1010 Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
1011 now contains a workaround, useful when loading a file generated by
1012 a buggy zic. (Problem and localtime.c fix reported by Bradley
1015 zdump -i now outputs non-hour numeric time zone abbreviations
1016 without a colon, e.g., "+0530" rather than "+05:30". This agrees
1017 with zic %z and with common practice, and simplifies auditing of
1020 zdump is now buildable again with -DUSE_LTZ=0.
1021 (Problem reported by Joseph Myers.)
1023 zdump.c now always includes private.h, to avoid code duplication
1024 with private.h. (Problem reported by Kees Dekker.)
1026 localtime.c no longer mishandles early or late timestamps
1027 when TZ is set to a POSIX-style string that specifies DST.
1028 (Problem reported by Kees Dekker.)
1030 date and strftime now cause %z to generate "-0000" instead of
1031 "+0000" when the UT offset is zero and the time zone abbreviation
1034 Changes to documentation and commentary
1036 The 'Theory' file now better documents choice of historical time
1037 zone abbreviations. (Problems reported by Michael Deckers.)
1039 tz-link.htm now covers leap smearing, which is popular in clouds.
1042 Release 2016j - 2016-11-22 23:17:13 -0800
1044 Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
1046 Changes to future timestamps
1048 Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
1049 This hives off a new zone Europe/Saratov from Europe/Volgograd.
1050 (Thanks to Yuri Konotopov and Stepan Golosunov.)
1052 Changes to past timestamps
1054 The new zone Asia/Atyrau for Atyraū Region, Kazakhstan, is like
1055 Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
1056 1999, not fall 1994. (Thanks to Stepan Golosunov.)
1058 Changes to past time zone abbreviations
1060 Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
1061 summer time before 1948. The old use of "EET" was a typo.
1065 zic no longer mishandles file systems that lack hard links, fixing
1066 bugs introduced in 2016g. (Problems reported by Tom Lane.)
1067 Also, when the destination already contains symbolic links, zic
1068 should now work better on systems where the 'link' system call
1069 does not follow symbolic links.
1071 Changes to documentation and commentary
1073 tz-link.htm now documents the relationship between release version
1074 numbers and development-repository commit tags. (Suggested by
1077 The 'Theory' file now documents UT.
1079 iso3166.tab now accents "Curaçao", and commentary now mentions
1080 the names "Cabo Verde" and "Czechia". (Thanks to Jiří Boháč.)
1083 Release 2016i - 2016-11-01 23:19:52 -0700
1085 Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
1086 reintroduces DST on 2016-11-06.
1088 Changes to future timestamps
1090 Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
1091 2017-01-15 at 03:00. Assume future observances in Tonga will be
1092 from the first Sunday in November through the third Sunday in
1093 January, like Fiji. (Thanks to Pulu ʻAnau.) Switch to numeric
1094 time zone abbreviations for this zone.
1096 Changes to past and future timestamps
1098 Northern Cyprus is now +03 year round, causing a split in Cyprus
1099 time zones starting 2016-10-30 at 04:00. This creates a zone
1100 Asia/Famagusta. (Thanks to Even Scharning and Matt Johnson.)
1102 Antarctica/Casey switched from +08 to +11 on 2016-10-22.
1103 (Thanks to Steffen Thorsen.)
1105 Changes to past timestamps
1107 Several corrections were made for pre-1975 timestamps in Italy.
1108 These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
1111 First, the 1893-11-01 00:00 transition in Italy used the new UT
1112 offset (+01), not the old (+00:49:56). (Thanks to Michael
1115 Second, rules for daylight saving in Italy were changed to agree
1116 with Italy's National Institute of Metrological Research (INRiM)
1117 except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
1118 Inglis, and Michael Deckers):
1120 The 1916-06-03 transition was at 24:00, not 00:00.
1122 The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
1125 The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
1128 The 1944-09-17 transition was at 03:00, not 01:00. This
1129 particular change is taken from Italian law as INRiM's table,
1130 (which says 02:00) appears to have a typo here. Also, keep the
1131 1944-04-03 transition for Europe/Rome, as Rome was controlled by
1134 The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
1139 The code should now be buildable on AmigaOS merely by setting the
1140 appropriate Makefile variables. (From a patch by Carsten Larsen.)
1143 Release 2016h - 2016-10-19 23:17:57 -0700
1145 Changes to future timestamps
1147 Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
1148 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that
1149 future fall transitions will be on the last Saturday of October
1150 at 01:00, which is consistent with predicted spring transitions
1151 on the last Saturday of March. (Thanks to Tim Parenti.)
1153 Changes to past timestamps
1155 In Turkey, transitions in 1986-1990 were at 01:00 standard time
1156 not at 02:00, and the spring 1994 transition was on March 20, not
1157 March 27. (Thanks to Kıvanç Yazan.)
1159 Changes to past and future time zone abbreviations
1161 Asia/Colombo now uses numeric time zone abbreviations like "+0530"
1162 instead of alphabetic ones like "IST" and "LKT". Various
1163 English-language sources use "IST", "LKT" and "SLST", with no
1164 working consensus. (Usage of "SLST" mentioned by Sadika
1169 zic no longer mishandles relativizing file names when creating
1170 symbolic links like /etc/localtime, when these symbolic links
1171 are outside the usual directory hierarchy. This fixes a bug
1172 introduced in 2016g. (Problem reported by Andreas Stieger.)
1174 Changes to build procedure
1176 New rules 'traditional_tarballs' and 'traditional_signatures' for
1177 building just the traditional-format distribution. (Requested by
1180 The file 'version' is now put into the tzdata tarball too.
1181 (Requested by Howard Hinnant.)
1183 Changes to documentation and commentary
1185 The 'Theory' file now has a section on interface stability.
1186 (Requested by Paul Koning.) It also mentions features like
1187 tm_zone and localtime_rz that have long been supported by the
1190 tz-link.htm has improved coverage of time zone boundaries suitable
1191 for geolocation. (Thanks to heads-ups from Evan Siroky and Matt
1194 The US commentary now mentions Allen and the "day of two noons".
1196 The Fiji commentary mentions the government's 2016-10-03 press
1197 release. (Thanks to Raymond Kumar.)
1200 Release 2016g - 2016-09-13 08:56:38 -0700
1202 Changes to future timestamps
1204 Turkey switched from EET/EEST (+02/+03) to permanent +03,
1205 effective 2016-09-07. (Thanks to Burak AYDIN.) Use "+03" rather
1206 than an invented abbreviation for the new time.
1208 New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
1209 (Thanks to Tim Parenti.)
1211 Changes to past timestamps
1213 For America/Los_Angeles, spring-forward transition times have been
1214 corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
1217 For zones using Soviet time on 1919-07-01, transitions to UT-based
1218 time were at 00:00 UT, not at 02:00 local time. The affected
1219 zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
1220 Europe/Ulyanovsk. (Thanks to Alexander Belopolsky.)
1222 Changes to past and future time zone abbreviations
1224 The Factory zone now uses the time zone abbreviation -00 instead
1225 of a long English-language string, as -00 is now the normal way to
1226 represent an undefined time zone.
1228 Several zones in Antarctica and the former Soviet Union, along
1229 with zones intended for ships at sea that cannot use POSIX TZ
1230 strings, now use numeric time zone abbreviations instead of
1231 invented or obsolete alphanumeric abbreviations. The affected
1232 zones are Antarctica/Casey, Antarctica/Davis,
1233 Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
1234 Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
1235 Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
1236 Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
1237 Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
1238 Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
1239 Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
1240 Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
1241 Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
1242 Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
1243 Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
1244 Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
1245 Europe/Minsk, Europe/Samara, Europe/Volgograd, and
1246 Indian/Kerguelen. For Europe/Moscow the invented abbreviation MSM
1247 was replaced by +05, whereas MSK and MSD were kept as they are not
1248 our invention and are widely used.
1250 Changes to zone names
1252 Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
1253 (Thanks to David Massoud.)
1257 zic no longer generates binary files containing POSIX TZ-like
1258 strings that disagree with the local time type after the last
1259 explicit transition in the data. This fixes a bug with
1260 Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
1261 on the reference platform. (Thanks to Alexander Belopolsky for
1262 reporting the bug and suggesting a way forward.)
1264 If the installed localtime and/or posixrules files are symbolic
1265 links, zic now keeps them symbolic links when updating them, for
1266 compatibility with platforms like OpenSUSE where other programs
1267 configure these files as symlinks.
1269 zic now avoids hard linking to symbolic links, avoids some
1270 unnecessary mkdir and stat system calls, and uses shorter file
1273 zdump has a new -i option to generate transitions in a
1274 more-compact but still human-readable format. This option is
1275 experimental, and the output format may change in future versions.
1276 (Thanks to Jon Skeet for suggesting that an option was needed,
1277 and thanks to Tim Parenti and Chris Rovick for further comments.)
1279 Changes to build procedure
1281 An experimental distribution format is available, in addition
1282 to the traditional format which will continue to be distributed.
1283 The new format is a tarball tzdb-VERSION.tar.lz with signature
1284 file tzdb-VERSION.tar.lz.asc. It unpacks to a top-level directory
1285 tzdb-VERSION containing the code and data of the traditional
1286 two-tarball format, along with extra data that may be useful.
1287 (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
1288 for comments about the experimental format.)
1290 The release version number is now more accurate in the usual case
1291 where releases are built from a Git repository. For example, if
1292 23 commits and some working-file changes have been made since
1293 release 2016g, the version number is now something like
1294 '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
1295 Tagged releases use the same version number format as before,
1296 e.g., '2016g'. To support the more-accurate version number, its
1297 specification has moved from a line in the Makefile to a new
1298 source file 'version'.
1300 The experimental distribution contains a file to2050.tzs that
1301 contains what should be the output of 'zdump -i -c 2050' on
1302 primary zones. If this file is available, 'make check' now checks
1303 that zdump generates this output.
1305 'make check_web' now works on Fedora-like distributions.
1307 Changes to documentation and commentary
1309 tzfile.5 now documents the new restriction on POSIX TZ-like
1310 strings that is now implemented by zic.
1312 Comments now cite URLs for some 1917-1921 Russian DST decrees.
1313 (Thanks to Alexander Belopolsky.)
1315 tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
1316 (thanks to Meno Hochschild) and ThreeTen-Extra, and its
1317 description of Java 8 has been brought up to date (thanks to
1318 Stephen Colebourne). Its description of local time on Mars has
1319 been updated to match current practice, and URLs have been updated
1320 and some obsolete ones removed.
1323 Release 2016f - 2016-07-05 16:26:51 +0200
1325 Changes affecting future timestamps
1327 The Egyptian government changed its mind on short notice, and
1328 Africa/Cairo will not introduce DST starting 2016-07-07 after all.
1329 (Thanks to Mina Samuel.)
1331 Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
1332 (Thanks to Stepan Golosunov.)
1334 Changes to past and future timestamps
1336 Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
1337 abbreviations instead of invented ones.
1339 Changes affecting past timestamps
1341 Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
1342 (Thanks to Stepan Golosunov.)
1345 Release 2016e - 2016-06-14 08:46:16 -0700
1347 Changes affecting future timestamps
1349 Africa/Cairo observes DST in 2016 from July 7 to the end of October.
1350 Guess October 27 and 24:00 transitions. (Thanks to Steffen Thorsen.)
1351 For future years, guess April's last Thursday to October's last
1352 Thursday except for Ramadan.
1354 Changes affecting past timestamps
1356 Locations while uninhabited now use '-00', not 'zzz', as a
1357 placeholder time zone abbreviation. This is inspired by Internet
1358 RFC 3339 and is more consistent with numeric time zone
1359 abbreviations already used elsewhere. The change affects several
1360 arctic and antarctic locations, e.g., America/Cambridge_Bay before
1361 1920 and Antarctica/Troll before 2005.
1363 Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
1364 at 03:00, not 23:00 the previous day. (Thanks to Michael Deckers.)
1368 zic now outputs a dummy transition at time 2**31 - 1 in zones
1369 whose POSIX-style TZ strings contain a '<'. This mostly works
1370 around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
1371 (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
1373 Changes affecting documentation and commentary
1375 tz-link.htm says why governments should give plenty of notice for
1376 time zone or DST changes, and refers to Matt Johnson's blog post.
1378 tz-link.htm mentions Tzdata for Elixir. (Thanks to Matt Johnson.)
1381 Release 2016d - 2016-04-17 22:50:29 -0700
1383 Changes affecting future timestamps
1385 America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
1386 (Thanks to Alexander Krivenyshev for the heads-up.)
1388 Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
1389 (Thanks to Alexander Krivenyshev and Matt Johnson.)
1391 New zone Asia/Tomsk, split off from Asia/Novosibirsk. It covers
1392 Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
1393 at 02:00. (Thanks to Stepan Golosunov.)
1395 Changes affecting past timestamps
1397 New zone Europe/Kirov, split off from Europe/Volgograd. It covers
1398 Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
1399 1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
1400 the same change. (Thanks to Stepan Golosunov.)
1402 Russia and nearby locations had daylight-saving transitions on
1403 1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
1404 1992-03-28 at 23:00 and 1992-09-26 at 23:00. (Thanks to Stepan
1407 Many corrections to historical time in Kazakhstan from 1991
1408 through 2005. (Thanks to Stepan Golosunov.) Replace Kazakhstan's
1409 invented time zone abbreviations with numeric abbreviations.
1411 Changes to commentary
1413 Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
1416 Release 2016c - 2016-03-23 00:51:27 -0700
1418 Changes affecting future timestamps
1420 Azerbaijan no longer observes DST. (Thanks to Steffen Thorsen.)
1422 Chile reverts from permanent to seasonal DST. (Thanks to Juan
1423 Correa for the heads-up, and to Tim Parenti for corrections.)
1424 Guess that future transitions are August's and May's second
1425 Saturdays at 24:00 mainland time. Also, call the period from
1426 2014-09-07 through 2016-05-14 daylight saving time instead of
1427 standard time, as that seems more appropriate now.
1429 Changes affecting past timestamps
1431 Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
1432 +02/+03 on 1989-03-26, not 1991-03-31. Europe/Volgograd changed
1433 from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
1434 (Thanks to Stepan Golosunov.)
1436 Changes to commentary
1438 Several updates and URLs for historical and proposed Russian changes.
1439 (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
1442 Release 2016b - 2016-03-12 17:30:14 -0800
1446 Starting with release 2016b, some data entries cause zic implementations
1447 derived from tz releases 2005j through 2015e to issue warnings like
1448 "time zone abbreviation differs from POSIX standard (+03)".
1449 These warnings should not otherwise affect zic's output and can safely be
1450 ignored on today's platforms, as the warnings refer to a restriction in
1451 POSIX.1-1988 that was removed in POSIX.1-2001. One way to suppress the
1452 warnings is to upgrade to zic derived from tz releases 2015f and later.
1454 Changes affecting future timestamps
1456 New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
1457 Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
1458 2016-03-27 at 02:00 local time. They need distinct zones since their
1459 post-1970 histories disagree. New zone Asia/Barnaul for Altai Krai and
1460 Altai Republic, Russia, which will switch from +06 to +07 on the same date
1461 and local time. The Astrakhan change is already official; the others have
1462 passed the first reading in the State Duma and are extremely likely.
1463 Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
1464 (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
1465 and Stepan Golosunov for followup.)
1467 As a trial of a new system that needs less information to be made up,
1468 the new zones use numeric time zone abbreviations like "+04"
1469 instead of invented abbreviations like "ASTT".
1471 Haiti will not observe DST in 2016. (Thanks to Jean Antoine via
1474 Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
1475 (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
1476 Saturday at 01:00, not March's last Friday at 24:00.
1478 Changes affecting past timestamps
1480 Europe/Chisinau observed DST during 1990, and switched from +04 to
1481 +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
1482 (Thanks to Stepan Golosunov.)
1484 1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
1485 KUYT/KUYST. (Thanks to Stepan Golosunov.)
1489 tzselect's diagnostics and checking, and checktab.awk's checking,
1490 have been improved. (Thanks to J William Piggott.)
1492 tzcode now builds under MinGW. (Thanks to Ian Abbott and Esben Haabendal.)
1494 tzselect now tests Julian-date TZ settings more accurately.
1495 (Thanks to J William Piggott.)
1497 Changes to commentary
1499 Comments in zone tables have been improved. (Thanks to J William Piggott.)
1501 tzselect again limits its menu comments so that menus fit on a
1502 24×80 alphanumeric display.
1504 A new web page tz-how-to.html. (Thanks to Bill Seymour.)
1506 In the Theory file, the description of possible time zone abbreviations in
1507 tzdata has been cleaned up, as the old description was unclear and
1508 inconsistent. (Thanks to Alain Mouette for reporting the problem.)
1511 Release 2016a - 2016-01-26 23:28:02 -0800
1513 Changes affecting future timestamps
1515 America/Cayman will not observe daylight saving this year after all.
1516 Revert our guess that it would. (Thanks to Matt Johnson.)
1518 Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
1519 (Thanks to Alexander Krivenyshev.)
1521 Asia/Tehran now has DST predictions for the year 2038 and later,
1522 to be March 21 00:00 to September 21 00:00. This is likely better
1523 than predicting no DST, albeit off by a day every now and then.
1525 Changes affecting past and future timestamps
1527 America/Metlakatla switched from PST all year to AKST/AKDT on
1528 2015-11-01 at 02:00. (Thanks to Steffen Thorsen.)
1530 America/Santa_Isabel has been removed, and replaced with a
1531 backward compatibility link to America/Tijuana. Its contents were
1532 apparently based on a misreading of Mexican legislation.
1534 Changes affecting past timestamps
1536 Asia/Karachi's two transition times in 2002 were off by a minute.
1537 (Thanks to Matt Johnson.)
1539 Changes affecting build procedure
1541 An installer can now combine leap seconds with use of the backzone file,
1542 e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
1543 The old 'make posix_packrat' rule is now marked as obsolescent.
1544 (Thanks to Ian Abbott for an initial implementation.)
1546 Changes affecting documentation and commentary
1548 A new file LICENSE makes it easier to see that the code and data
1549 are mostly public-domain. (Thanks to James Knight.) The three
1550 non-public-domain files now use the current (3-clause) BSD license
1551 instead of older versions of that license.
1553 tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
1554 CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
1555 on editing tz source files (with a mention of Sublime zoneinfo,
1556 thanks to Gilmore Davidson).
1558 The Theory and asia files now mention the 2015 book "The Global
1559 Transformation of Time, 1870-1950", and cite a couple of reviews.
1561 The America/Chicago entry now documents the informal use of US
1562 central time in Fort Pierre, South Dakota. (Thanks to Rick
1563 McDermid, Matt Johnson, and Steve Jones.)
1566 Release 2015g - 2015-10-01 00:39:51 -0700
1568 Changes affecting future timestamps
1570 Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
1573 Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
1574 (Thanks to Alexander Krivenyshev.)
1576 Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
1577 (Thanks to Ken Rylander.)
1579 Fort Nelson, British Columbia will not fall back on 2015-11-01. It has
1580 effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
1581 New zone America/Fort_Nelson. (Thanks to Matt Johnson.)
1583 Changes affecting past timestamps
1585 Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
1587 Changes affecting code
1589 localtime no longer mishandles America/Anchorage after 2037.
1590 (Thanks to Bradley White for reporting the bug.)
1592 On hosts with signed 32-bit time_t, localtime no longer mishandles
1593 Pacific/Fiji after 2038-01-16 14:00 UTC.
1595 The localtime module allows the variables 'timezone', 'daylight',
1596 and 'altzone' to be in common storage shared with other modules,
1597 and declares them in case the system <time.h> does not.
1598 (Problems reported by Kees Dekker.)
1600 On platforms with tm_zone, strftime.c now assumes it is not NULL.
1601 This simplifies the code and is consistent with zdump.c.
1602 (Problem reported by Christos Zoulas.)
1604 Changes affecting documentation
1606 The tzfile man page now documents that transition times denote the
1607 starts (not the ends) of the corresponding time periods.
1608 (Ambiguity reported by Bill Seymour.)
1611 Release 2015f - 2015-08-10 18:06:56 -0700
1613 Changes affecting future timestamps
1615 North Korea switches to +0830 on 2015-08-15. (Thanks to Steffen Thorsen.)
1616 The abbreviation remains "KST". (Thanks to Robert Elz.)
1618 Uruguay no longer observes DST. (Thanks to Steffen Thorsen
1621 Changes affecting past and future timestamps
1623 Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
1624 (Thanks to Roman Tudos.)
1626 Changes affecting data format and code
1628 zic's '-y YEARISTYPE' option is no longer documented. The TYPE
1629 field of a Rule line should now be '-'; the old values 'even',
1630 'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
1631 Although the implementation has not changed, these features do not
1632 work in the default installation, they are not used in the data,
1633 and they are now considered obsolescent.
1635 zic now checks that two rules don't take effect at the same time.
1636 (Thanks to Jon Skeet and Arthur David Olson.) Constraints on
1637 simultaneity are now documented.
1639 The two characters '%z' in a zone format now stand for the UT
1640 offset, e.g., '-07' for seven hours behind UT and '+0530' for
1641 five hours and thirty minutes ahead. This better supports time
1642 zone abbreviations conforming to POSIX.1-2001 and later.
1644 Changes affecting installed data files
1646 Comments for America/Halifax and America/Glace_Bay have been improved.
1647 (Thanks to Brian Inglis.)
1649 Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
1650 Europe/Sofia, and Europe/Tallinn. This yields slightly smaller
1651 installed data files for Europe/Simferopol and Europe/Tallinn.
1652 It does not affect timestamps. (Thanks to Howard Hinnant.)
1654 Changes affecting code
1656 zdump and zic no longer warn about valid time zone abbreviations
1659 Some Visual Studio 2013 warnings have been suppressed.
1660 (Thanks to Kees Dekker.)
1662 'date' no longer sets the time of day and its -a, -d, -n and -t
1663 options have been removed. Long obsolescent, the implementation
1664 of these features had porting problems. Builders no longer need
1665 to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
1666 (Thanks to Kees Dekker for pointing out the problem.)
1668 Changes affecting documentation
1670 The Theory file mentions naming issues earlier, as these seem to be
1671 poorly publicized (thanks to Gilmore Davidson for reporting the problem).
1673 tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
1675 Mention that Herbert Samuel introduced the term "Summer Time".
1678 Release 2015e - 2015-06-13 10:56:02 -0700
1680 Changes affecting future timestamps
1682 Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
1683 not 06-13 and 07-18 as we had guessed. (Thanks to Milamber.)
1685 Assume Cayman Islands will observe DST starting next year, using US rules.
1686 Although it isn't guaranteed, it is the most likely.
1688 Changes affecting data format
1690 The file 'iso3166.tab' now uses UTF-8, so that its entries can better
1691 spell the names of Åland Islands, Côte d'Ivoire, and Réunion.
1693 Changes affecting code
1695 When displaying data, tzselect converts it to the current locale's
1696 encoding if the iconv command works. (Problem reported by random832.)
1698 tzselect no longer mishandles Dominica, fixing a bug introduced
1699 in Release 2014f. (Problem reported by Owen Leibman.)
1701 zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
1702 This fixes a bug introduced in Release 2014f.
1703 (Problem reported by Leonardo Chiquitto.)
1706 Release 2015d - 2015-04-24 08:09:46 -0700
1708 Changes affecting future timestamps
1710 Egypt will not observe DST in 2015 and will consider canceling it
1711 permanently. For now, assume no DST indefinitely.
1712 (Thanks to Ahmed Nazmy and Tim Parenti.)
1714 Changes affecting past timestamps
1716 America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
1717 1966-07-01. Also, Yukon's time zone history is documented better.
1718 (Thanks to Brian Inglis and Dennis Ferguson.)
1720 Change affecting past and future time zone abbreviations
1722 The abbreviations for Hawaii-Aleutian standard and daylight times
1723 have been changed from HAST/HADT to HST/HDT, as per US Government
1724 Printing Office style. This affects only America/Adak since 1983,
1725 as America/Honolulu was already using the new style.
1727 Changes affecting code
1729 zic has some minor performance improvements.
1732 Release 2015c - 2015-04-11 08:55:55 -0700
1734 Changes affecting future timestamps
1736 Egypt's spring-forward transition is at 24:00 on April's last Thursday,
1737 not 00:00 on April's last Friday. 2015's transition will therefore be on
1738 Thursday, April 30 at 24:00, not Friday, April 24 at 00:00. Similar fixes
1739 apply to 2026, 2037, 2043, etc. (Thanks to Steffen Thorsen.)
1741 Changes affecting past timestamps
1743 The following changes affect some pre-1991 Chile-related timestamps
1744 in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
1746 The 1910 transition was January 10, not January 1.
1748 The 1918 transition was September 10, not September 1.
1750 The UT -04 time observed from 1932 to 1942 is now considered to
1751 be standard time, not year-round DST.
1753 Santiago observed DST (UT -03) from 1946-07-15 through
1754 1946-08-31, then reverted to standard time, then switched to -05
1757 Assume transitions before 1968 were at 00:00, since we have no data
1760 The spring 1988 transition was 1988-10-09, not 1988-10-02.
1761 The fall 1990 transition was 1990-03-11, not 1990-03-18.
1763 Assume no UT offset change for Pacific/Easter on 1890-01-01,
1764 and omit all transitions on Pacific/Easter from 1942 through 1946
1765 since we have no data suggesting that they existed.
1767 One more zone has been turned into a link, as it differed
1768 from an existing zone only for older timestamps. As usual,
1769 this change affects UT offsets in pre-1970 timestamps only.
1770 The zone's old contents have been moved to the 'backzone' file.
1771 The affected zone is America/Montreal.
1773 Changes affecting commentary
1775 Mention the TZUpdater tool.
1777 Mention "The Time Now". (Thanks to Brandon Ramsey.)
1780 Release 2015b - 2015-03-19 23:28:11 -0700
1782 Changes affecting future timestamps
1784 Mongolia will start observing DST again this year, from the last
1785 Saturday in March at 02:00 to the last Saturday in September at 00:00.
1786 (Thanks to Ganbold Tsagaankhuu.)
1788 Palestine will start DST on March 28, not March 27. Also,
1789 correct the fall 2014 transition from September 26 to October 24.
1790 Adjust future predictions accordingly. (Thanks to Steffen Thorsen.)
1792 Changes affecting past timestamps
1794 The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
1795 regression. (Thanks to Stuart Bishop for reporting the problem.)
1797 Some more zones have been turned into links, when they differed
1798 from existing zones only for older timestamps. As usual,
1799 these changes affect UT offsets in pre-1970 timestamps only.
1800 Their old contents have been moved to the 'backzone' file.
1801 The affected zones are: America/Antigua, America/Cayman,
1802 Pacific/Midway, and Pacific/Saipan.
1804 Changes affecting time zone abbreviations
1806 Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
1809 Changes affecting code
1811 Fix integer overflow bug in reference 'mktime' implementation.
1812 (Problem reported by Jörg Richter.)
1814 Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
1815 to be used in the same executable as standard-library time_t functions.
1816 (Problems reported by Bradley White.)
1818 Changes affecting commentary
1820 Cite the recent Mexican decree changing Quintana Roo's time zone.
1821 (Thanks to Carlos Raúl Perasso.)
1823 Likewise for the recent Chilean decree. (Thanks to Eduardo Romero Urra.)
1825 Update info about Mars time.
1828 Release 2015a - 2015-01-29 22:35:20 -0800
1830 Changes affecting future timestamps
1832 The Mexican state of Quintana Roo, represented by America/Cancun,
1833 will shift from Central Time with DST to Eastern Time without DST
1834 on 2015-02-01 at 02:00. (Thanks to Steffen Thorsen and Gwillim Law.)
1836 Chile will not change clocks in April or thereafter; its new standard time
1837 will be its old daylight saving time. This affects America/Santiago,
1838 Pacific/Easter, and Antarctica/Palmer. (Thanks to Juan Correa.)
1840 New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
1841 (Thanks to Tim Parenti.)
1843 Changes affecting past timestamps
1845 Iceland observed DST in 1919 and 1921, and its 1939 fallback
1846 transition was Oct. 29, not Nov. 29. Remove incorrect data from
1847 Shanks about time in Iceland between 1837 and 1908.
1849 Some more zones have been turned into links, when they differed
1850 from existing zones only for older timestamps. As usual,
1851 these changes affect UT offsets in pre-1970 timestamps only.
1852 Their old contents have been moved to the 'backzone' file.
1853 The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
1856 Changes affecting code
1858 tzalloc now scrubs time zone abbreviations compatibly with the way
1859 that tzset always has, by replacing invalid bytes with '_' and by
1860 shortening too-long abbreviations.
1862 tzselect ports to POSIX awk implementations, no longer mishandles
1863 POSIX TZ settings when GNU awk is used, and reports POSIX TZ
1864 settings to the user. (Thanks to Stefan Kuhn.)
1866 Changes affecting build procedure
1868 'make check' now checks for links to links in the data.
1869 One such link (for Africa/Asmera) has been fixed.
1870 (Thanks to Stephen Colebourne for pointing out the problem.)
1872 Changes affecting commentary
1874 The leapseconds file commentary now mentions the expiration date.
1875 (Problem reported by Martin Burnicki.)
1877 Update Mexican Library of Congress URL.
1880 Release 2014j - 2014-11-10 17:37:11 -0800
1882 Changes affecting current and future timestamps
1884 Turks & Caicos' switch from US eastern time to UT -04 year-round
1885 did not occur on 2014-11-02 at 02:00. It's currently scheduled
1886 for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
1888 Changes affecting past timestamps
1890 Many pre-1989 timestamps have been corrected for Asia/Seoul and
1891 Asia/Pyongyang, based on sources for the Korean-language Wikipedia
1892 entry for time in Korea. (Thanks to Sanghyuk Jung.) Also, no
1893 longer guess that Pyongyang mimicked Seoul time after World War II,
1894 as this is politically implausible.
1896 Some more zones have been turned into links, when they differed
1897 from existing zones only for older timestamps. As usual,
1898 these changes affect UT offsets in pre-1970 timestamps only.
1899 Their old contents have been moved to the 'backzone' file.
1900 The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
1901 Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
1902 Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
1905 Changes affecting commentary
1907 The commentary is less enthusiastic about Shanks as a source,
1908 and is more careful to distinguish UT from UTC.
1911 Release 2014i - 2014-10-21 22:04:57 -0700
1913 Changes affecting future timestamps
1915 Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
1916 (Thanks to Ken Rylander for the heads-up.) Guess that future
1917 years will use a similar pattern.
1919 A new Zone Pacific/Bougainville, for the part of Papua New Guinea
1920 that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
1921 (Thanks to Kiley Walbom for the heads-up.)
1923 Changes affecting time zone abbreviations
1925 Since Belarus is not changing its clocks even though Moscow is,
1926 the time zone abbreviation in Europe/Minsk is changing from FET
1927 to its more-traditional value MSK on 2014-10-26 at 01:00.
1928 (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
1930 The new abbreviation IDT stands for the pre-1976 use of UT +08 in
1931 Indochina, to distinguish it better from ICT (+07).
1933 Changes affecting past timestamps
1935 Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
1936 (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
1937 authoritative book). Asia/Ho_Chi_Minh has been added to
1938 zone1970.tab, to give tzselect users in Vietnam two choices,
1939 since north and south Vietnam disagreed after our 1970 cutoff.
1941 Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
1942 they differed from existing zones only for older timestamps. As
1943 usual, these changes affect pre-1970 timestamps only. Their old
1944 contents have been moved to the 'backzone' file.
1946 Changes affecting code
1948 The time-related library functions now set errno on failure, and
1949 some crashes in the new tzalloc-related library functions have
1950 been fixed. (Thanks to Christos Zoulas for reporting most of
1951 these problems and for suggesting fixes.)
1953 If USG_COMPAT is defined and the requested timestamp is standard time,
1954 the tz library's localtime and mktime functions now set the extern
1955 variable timezone to a value appropriate for that timestamp; and
1956 similarly for ALTZONE, daylight saving time, and the altzone variable.
1957 This change is a companion to the tzname change in 2014h, and is
1958 designed to make timezone and altzone more compatible with tzname.
1960 The tz library's functions now set errno to EOVERFLOW if they fail
1961 because the result cannot be represented. ctime and ctime_r now
1962 return NULL and set errno when a timestamp is out of range, rather
1963 than having undefined behavior.
1965 Some bugs associated with the new 2014g functions have been fixed.
1966 This includes a bug that largely incapacitated the new functions
1967 time2posix_z and posix2time_z. (Thanks to Christos Zoulas.)
1968 It also includes some uses of uninitialized variables after tzalloc.
1969 The new code uses the standard type 'ssize_t', which the Makefile
1970 now gives porting advice about.
1972 Changes affecting commentary
1974 Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
1977 Release 2014h - 2014-09-25 18:59:03 -0700
1979 Changes affecting past timestamps
1981 America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
1983 Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
1984 not 1920-01-06. The old entry was based on a misinterpretation of Shanks.
1986 Some more zones have been turned into links, when they differed
1987 from existing zones only for older timestamps. As usual,
1988 these changes affect UT offsets in pre-1970 timestamps only.
1989 Their old contents have been moved to the 'backzone' file.
1990 The affected zones are: Africa/Blantyre, Africa/Bujumbura,
1991 Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
1992 Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
1994 Changes affecting code
1996 zdump -V and -v now output gmtoff= values on all platforms,
1997 not merely on platforms defining TM_GMTOFF.
1999 The tz library's localtime and mktime functions now set tzname to a value
2000 appropriate for the requested timestamp, and zdump now uses this
2001 on platforms not defining TM_ZONE, fixing a 2014g regression.
2002 (Thanks to Tim Parenti for reporting the problem.)
2004 The tz library no longer sets tzname if localtime or mktime fails.
2006 zdump -c no longer mishandles transitions near year boundaries.
2007 (Thanks to Tim Parenti for reporting the problem.)
2009 An access to uninitialized data has been fixed.
2010 (Thanks to Jörg Richter for reporting the problem.)
2012 When THREAD_SAFE is defined, the code ports to the C11 memory model.
2013 A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
2014 and two threads race to initialize data used by gmtime-like functions.
2015 (Thanks to Andy Heninger for reporting the problems.)
2017 Changes affecting build procedure
2019 'make check' now checks better for properly-sorted data.
2021 Changes affecting documentation and commentary
2023 zdump's gmtoff=N output is now documented, and its isdst=D output
2024 is now documented to possibly output D values other than 0 or 1.
2026 zdump -c's treatment of years is now documented to use the
2027 Gregorian calendar and Universal Time without leap seconds,
2028 and its behavior at cutoff boundaries is now documented better.
2029 (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
2031 Programs are now documented to use the proleptic Gregorian calendar.
2032 (Thanks to Alan Barrett for the suggestion.)
2034 Fractional-second GMT offsets have been documented for civil time
2035 in 19th-century Chennai, Jakarta, and New York.
2038 Release 2014g - 2014-08-28 12:31:23 -0700
2040 Changes affecting future timestamps
2042 Turks & Caicos is switching from US eastern time to UT -04
2043 year-round, modeled as a switch on 2014-11-02 at 02:00.
2044 [As noted in 2014j, this switch was later delayed.]
2046 Changes affecting past timestamps
2048 Time in Russia or the USSR before 1926 or so has been corrected by
2049 a few seconds in the following zones: Asia/Irkutsk,
2050 Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
2051 Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara. For
2052 Asia/Yekaterinburg the correction is a few minutes. (Thanks to
2053 Vladimir Karpinsky.)
2055 The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
2056 This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
2057 Atlantic/Azores, and Atlantic/Madeira. Also, Lisbon's pre-1912
2058 GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
2059 (Thanks to Stephen Colebourne for pointing to the decree.)
2061 Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
2063 A new file 'backzone' contains data which may appeal to
2064 connoisseurs of old timestamps, although it is out of scope for
2065 the tz database, is often poorly sourced, and contains some data
2066 that is known to be incorrect. The new file is not recommended
2067 for ordinary use and its entries are not installed by default.
2068 (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
2069 Isle of Man entries.)
2071 Some more zones have been turned into links, when they differed
2072 from existing zones only for older timestamps. As usual,
2073 these changes affect UT offsets in pre-1970 timestamps only.
2074 Their old contents have been moved to the 'backzone' file.
2075 The affected zones are: Africa/Bangui, Africa/Brazzaville,
2076 Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
2077 Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
2079 Changes affecting code
2081 Unless NETBSD_INSPIRED is defined to 0, the tz library now
2082 supplies functions for creating and using objects that represent
2083 timezones. The new functions are tzalloc, tzfree, localtime_rz,
2084 mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
2085 time2posix_z. They are intended for performance: for example,
2086 localtime_rz (unlike localtime_r) is trivially thread-safe without
2087 locking. (Thanks to Christos Zoulas for proposing NetBSD-inspired
2088 functions, and to Alan Barrett and Jonathan Lennox for helping to
2091 zdump now builds with the tz library unless USE_LTZ is defined to 0,
2092 This lets zdump use tz features even if the system library lacks them.
2093 To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
2094 TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
2096 zdump now uses localtime_rz if available, as it's significantly faster,
2097 and it can help zdump better diagnose invalid timezone names.
2098 Define HAVE_LOCALTIME_RZ to 0 to suppress this. HAVE_LOCALTIME_RZ
2099 defaults to 1 if NETBSD_INSPIRED && USE_LTZ. When localtime_rz is
2100 not available, zdump now uses localtime_r and tzset if available,
2101 as this is a bit cleaner and faster than plain localtime. Compile
2102 with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
2103 lacks these two functions.
2105 If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
2106 Although not needed for tz's own applications, which are single-threaded,
2107 this supports POSIX better if the tz library is used in multithreaded apps.
2109 Some crashes have been fixed when zdump or the tz library is given
2110 invalid or outlandish input.
2112 The tz library no longer mishandles leap seconds on platforms with
2113 unsigned time_t in timezones that lack ordinary transitions after 1970.
2115 The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
2116 already defined, to make it easier to configure on common platforms.
2117 Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
2119 Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
2120 assumes that reading uninitialized memory yields garbage values
2121 but does not cause other problems such as traps.
2123 If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
2124 more likely to guess right for ambiguous timestamps near
2125 transitions where tm_isdst does not change.
2127 If HAVE_STRFTIME_L is defined to 1, the tz library now defines
2128 strftime_l for compatibility with recent versions of POSIX.
2129 Only the C locale is supported, though. HAVE_STRFTIME_L defaults
2130 to 1 on recent POSIX versions, and to 0 otherwise.
2132 tzselect -c now uses a hybrid distance measure that works better
2133 in Africa. (Thanks to Alan Barrett for noting the problem.)
2135 The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
2136 or when time_tz is defined.
2138 When HAVE_UTMPX_H is set the 'date' command now builds on systems
2139 whose <utmpx.h> file does not define WTMPX_FILE, and when setting
2140 the date it updates the wtmpx file if _PATH_WTMPX is defined.
2141 This affects GNU/Linux and similar systems.
2143 For easier maintenance later, some C code has been simplified,
2144 some lint has been removed, and the code has been tweaked so that
2145 plain 'make' is more likely to work.
2147 The C type 'bool' is now used for boolean values, instead of 'int'.
2149 The long-obsolete LOCALE_HOME code has been removed.
2151 The long-obsolete 'gtime' function has been removed.
2153 Changes affecting build procedure
2155 'zdump' no longer links in ialloc.o, as it's not needed.
2157 'make check_time_t_alternatives' no longer assumes GNU diff.
2159 Changes affecting distribution tarballs
2161 The files checktab.awk and zoneinfo2tdf.pl are now distributed in
2162 the tzdata tarball instead of the tzcode tarball, since they help
2163 maintain the data. The NEWS and Theory files are now also
2164 distributed in the tzdata tarball, as they're relevant for data.
2165 (Thanks to Alan Barrett for pointing this out.) Also, the
2166 leapseconds.awk file is no longer distributed in the tzcode
2167 tarball, since it belongs in the tzdata tarball (where 2014f
2168 inadvertently also distributed it).
2170 Changes affecting documentation and commentary
2172 A new file CONTRIBUTING is distributed. (Thanks to Tim Parenti for
2173 suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
2176 The man pages have been updated to use function prototypes,
2177 to document thread-safe variants like localtime_r, and to document
2178 the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
2181 The fields in Link lines have been renamed to be more descriptive
2182 and more like the parameters of 'ln'. LINK-FROM has become TARGET,
2183 and LINK-TO has become LINK-NAME.
2185 tz-link.htm mentions the IETF's tzdist working group; Windows
2186 Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
2188 Some broken URLs have been fixed in the commentary. (Thanks to
2191 Commentary about Philippines DST has been updated, and commentary
2192 on pre-1970 time in India has been added.
2195 Release 2014f - 2014-08-05 17:42:36 -0700
2197 Changes affecting future timestamps
2199 Russia will subtract an hour from most of its time zones on 2014-10-26
2200 at 02:00 local time. (Thanks to Alexander Krivenyshev.)
2201 There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
2202 Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
2203 (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
2204 (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
2205 (Europe/Samara) are not changing their clocks. The changed zones are
2206 Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
2207 Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
2208 Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
2209 Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
2210 subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
2211 but not its UTC offset. Two zones are added: Asia/Chita (split
2212 from Asia/Yakutsk, and also with two hours subtracted) and
2213 Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
2214 subtracted). (Thanks to Tim Parenti for much of the above.)
2216 Changes affecting time zone abbreviations
2218 Australian eastern time zone abbreviations are now AEST/AEDT not EST,
2219 and similarly for the other Australian zones. That is, for eastern
2220 standard and daylight saving time the abbreviations are AEST and AEDT
2221 instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
2222 and AWST/AWDT are now used instead of the former CST, CWST, and WST.
2223 This change does not affect UT offsets, only time zone abbreviations.
2224 (Thanks to Rich Tibbett and many others.)
2226 Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
2227 effective 2014-10-26 at 02:00 local time.
2229 The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
2230 has been changed from URUT to XJT. (Thanks to Luther Ma.)
2232 Prefer MSK/MSD for Moscow time in Russia, even in other cities.
2233 Similarly, prefer EET/EEST for eastern European time in Russia.
2235 Change time zone abbreviations in (western) Samoa to use "ST" and
2236 "DT" suffixes, as this is more likely to match common practice.
2237 Prefix "W" to (western) Samoa time when its standard-time offset
2238 disagrees with that of American Samoa.
2240 America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
2242 Time zone abbreviations have been updated for Japan's two time
2243 zones used 1896-1937. JWST now stands for Western Standard
2244 Time, and JCST for Central Standard Time (formerly this was CJT).
2245 These abbreviations are now used for time in Korea, Taiwan,
2246 and Sakhalin while controlled by Japan.
2248 Changes affecting past timestamps
2250 China's five zones have been simplified to two, since the post-1970
2251 differences in the other three seem to have been imaginary. The
2252 zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
2253 removed; backwards-compatibility links still work, albeit with
2254 different behaviors for timestamps before May 1980. Asia/Urumqi's
2255 1980 transition to UT +08 has been removed, so that it is now at
2256 +06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
2257 Treindl sent helpful translations of two papers by Guo Qingsheng.)
2259 Some zones have been turned into links, when they differed from existing
2260 zones only for older UT offsets where data entries were likely invented.
2261 These changes affect UT offsets in pre-1970 timestamps only. This is
2262 similar to the change in release 2013e, except this time for western
2263 Africa. The affected zones are: Africa/Bamako, Africa/Banjul,
2264 Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
2265 Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
2266 Atlantic/St_Helena. This also affects the backwards-compatibility
2267 link Africa/Timbuktu. (Thanks to Alan Barrett, Stephen Colebourne,
2268 Tim Parenti, and David Patte for reporting problems in earlier
2269 versions of this change.)
2271 Asia/Shanghai's pre-standard-time UT offset has been changed from
2272 8:05:57 to 8:05:43, the location of Xujiahui Observatory. Its
2273 transition to standard time has been changed from 1928 to 1901.
2275 Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
2276 then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
2277 In 1946 it observed DST from 05-15 through 09-30; in 1947
2278 from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
2279 (Thanks to Yu-Cheng Chuang.)
2281 Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
2283 Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
2284 10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
2286 Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
2287 period from 1911 to 1950.
2289 Pacific/Chatham has been changed to New Zealand standard time plus
2290 45 minutes for the period before 1957, reflecting a 1956 remark in
2291 the New Zealand parliament.
2293 Europe/Budapest has several pre-1946 corrections: in 1918 the transition
2294 out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
2295 1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
2296 not 04-06 at 02:00; and there was no DST in 1920.
2298 Africa/Accra is now assumed to have observed DST from 1920 through 1935.
2300 Time in Russia before 1927 or so has been corrected by a few seconds in
2301 the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
2302 Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
2303 Europe/Riga. Also, Moscow's location has been changed to its Kilometer 0
2304 point. (Thanks to Vladimir Karpinsky for the Moscow changes.)
2306 Changes affecting data format
2308 A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
2309 The new file's extended format allows multiple country codes per zone.
2310 The older file is still installed but is deprecated; its format is
2311 not changing and it will still be distributed for a while, but new
2312 applications should use the new file.
2314 The new file format simplifies maintenance of obscure locations.
2315 To test this, it adds coverage for the Crozet Islands and the
2316 Scattered Islands. (Thanks to Tobias Conradi and Antoine Leca.)
2318 The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
2319 It is still ASCII now, but commentary about the switch has been added.
2320 The new file 'zone1970.tab' already uses UTF-8.
2322 Changes affecting code
2324 'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
2325 is defined. (Thanks to Elliott Hughes for reporting the problem.)
2327 'zic' no longer mishandles input when ignoring case in locales that
2328 are not compatible with English, e.g., unibyte Turkish locales when
2329 compiled with HAVE_GETTEXT.
2331 Error diagnostics of 'zic' and 'yearistype' have been reworded so that
2332 they no longer use ASCII '-' as if it were a dash.
2334 'zic' now rejects output file names that contain '.' or '..' components.
2335 (Thanks to Tim Parenti for reporting the problem.)
2337 'zic -v' now warns about output file names that do not follow
2338 POSIX rules, or that contain a digit or '.'. (Thanks to Arthur
2339 David Olson for starting the ball rolling on this.)
2341 Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
2343 Changes affecting build procedure
2345 'zic' no longer links in localtime.o and asctime.o, as they're not needed.
2346 (Thanks to John Cochran.)
2348 Changes affecting documentation and commentary
2350 The 'Theory' file documents legacy names, the longstanding
2351 exceptions to the POSIX-inspired file name rules.
2353 The 'zic' documentation clarifies the role of time types when
2354 interpreting dates. (Thanks to Arthur David Olson.)
2356 Documentation and commentary now prefer UTF-8 to US-ASCII,
2357 allowing the use of proper accents in foreign words and names.
2358 Code and data have not changed because of this. (Thanks to
2359 Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
2362 Non-HTML documentation and commentary now use plain-text URLs instead of
2363 HTML insertions, and are more consistent about bracketing URLs when they
2364 are not already surrounded by white space. (Thanks to suggestions by
2367 There is new commentary about Xujiahui Observatory, the five time-zone
2368 project in China from 1918 to 1949, timekeeping in Japanese-occupied
2369 Shanghai, and Tibet Time in the 1950s. The sharp-eyed can spot the
2370 warlord Jin Shuren in the data.
2372 Commentary about the coverage of each Russian zone has been standardized.
2373 (Thanks to Tim Parenti.)
2375 There is new commentary about contemporary timekeeping in Ethiopia.
2377 Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
2379 There is new commentary about time in Poland in 1919.
2381 Proper credit has been given to DST inventor George Vernon Hudson.
2383 Commentary about time in Metlakatla, AK and Resolute, NU has been
2384 improved, with a new source for the former.
2386 In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
2389 Commentary about permanent Antarctic bases has been updated.
2391 Several typos have been corrected. (Thanks to Tim Parenti for
2392 contributing some of these fixes.)
2394 tz-link.htm now mentions the JavaScript libraries Moment Timezone,
2395 TimezoneJS.Date, Walltime-js, and Timezone. (Thanks to a heads-up
2396 from Matt Johnson.) Also, it mentions the Go 'latlong' package.
2397 (Thanks to a heads-up from Dirkjan Ochtman.)
2399 The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
2400 have been removed. These obsolescent US Naval Observatory entries were no
2401 longer helpful for maintenance. (Thanks to Tim Parenti for the suggestion.)
2404 Release 2014e - 2014-06-12 21:53:52 -0700
2406 Changes affecting near-future timestamps
2408 Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
2409 (Thanks to Imed Chihi.) Guess that from 2015 on Egypt will temporarily
2410 switch to standard time at 24:00 the last Thursday before Ramadan, and
2411 back to DST at 00:00 the first Friday after Ramadan.
2413 Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00. (Thanks
2414 to Milamber Space Network.) Guess that from 2015 on Morocco will
2415 temporarily switch to standard time at 03:00 the last Saturday before
2416 Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
2418 Changes affecting past timestamps
2420 The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
2421 "MSD" for Moscow's double daylight time in summer 1921. Also, a typo
2422 "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
2423 in 1991. (Thanks to Hank W. for reporting the problems.)
2425 Changes affecting commentary
2427 tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
2428 draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
2429 removes stale pointers to World Time Explorer and WORLDTIME.
2432 Release 2014d - 2014-05-27 21:34:40 -0700
2434 Changes affecting code
2436 zic no longer generates files containing timestamps before the Big Bang.
2437 This works around GNOME glib bug 878
2438 <https://gitlab.gnome.org/GNOME/glib/issues/878>
2439 (Thanks to Leonardo Chiquitto for reporting the bug, and to
2440 Arthur David Olson and James Cloos for suggesting improvements to the fix.)
2442 Changes affecting documentation
2444 tz-link.htm now mentions GNOME.
2447 Release 2014c - 2014-05-13 07:44:13 -0700
2449 Changes affecting near-future timestamps
2451 Egypt observes DST starting 2014-05-15 at 24:00.
2452 (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
2453 Details have not been announced, except that DST will not be observed
2454 during Ramadan. Guess that DST will stop during the same Ramadan dates as
2455 Morocco, and that Egypt's future spring and fall transitions will be the
2456 same as 2010 when it last observed DST, namely April's last Friday at
2457 00:00 to September's last Thursday at 23:00 standard time. Also, guess
2458 that Ramadan transitions will be at 00:00 standard time.
2460 Changes affecting code
2462 zic now generates transitions for minimum time values, eliminating guesswork
2463 when handling low-valued timestamps. (Thanks to Arthur David Olson.)
2465 Port to Cygwin sans glibc. (Thanks to Arthur David Olson.)
2467 Changes affecting commentary and documentation
2469 Remove now-confusing comment about Jordan. (Thanks to Oleksii Nochovnyi.)
2472 Release 2014b - 2014-03-24 21:28:50 -0700
2474 Changes affecting near-future timestamps
2476 Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
2477 (Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
2479 New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and
2480 Bengt-Inge Larsson.) This is currently an approximation; a better version
2481 will require the zic and localtime fixes mentioned below, and the plan is
2482 to wait for a while until at least the zic fixes propagate.
2484 Changes affecting code
2486 'zic' and 'localtime' no longer reject locations needing four transitions
2487 per year for the foreseeable future. (Thanks to Andrew Main (Zefram).)
2488 Also, 'zic' avoids some unlikely failures due to integer overflow.
2490 Changes affecting build procedure
2492 'make check' now detects Rule lines defined but never used.
2493 The NZAQ rules, an instance of this problem, have been removed.
2495 Changes affecting commentary and documentation
2497 Fix Tuesday/Thursday typo in description of time in Israel.
2498 (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
2500 Microsoft Windows 8.1 doesn't support tz database names. (Thanks
2501 to Donald MacQueen.) Instead, the Microsoft Windows Store app
2502 library supports them.
2504 Add comments about Johnston Island time in the 1960s.
2505 (Thanks to Lyle McElhaney.)
2507 Morocco's 2014 DST start will be as predicted.
2508 (Thanks to Sebastien Willemijns.)
2511 Release 2014a - 2014-03-07 23:30:29 -0800
2513 Changes affecting near-future timestamps
2515 Turkey begins DST on 2014-03-31, not 03-30. (Thanks to Faruk Pasin for
2516 the heads-up, and to Tim Parenti for simplifying the update.)
2518 Changes affecting past timestamps
2520 Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
2521 (Thanks to Steffen Thorsen.)
2523 Ukraine switched from Moscow to Eastern European time on 1990-07-01
2524 (not 1992-01-01), and observed DST during the entire next winter.
2525 (Thanks to Vladimir in Moscow via Alois Treindl.)
2527 In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
2528 (Thanks to Avigdor Finkelstein.)
2530 Changes affecting code
2532 A uninitialized-storage bug in 'localtime' has been fixed.
2533 (Thanks to Logan Chien.)
2535 Changes affecting the build procedure
2537 The settings for 'make check_web' now default to Ubuntu 13.10.
2539 Changes affecting commentary and documentation
2541 The boundary of the US Pacific time zone is given more accurately.
2542 (Thanks to Alan Mintz.)
2544 Chile's 2014 DST will be as predicted. (Thanks to José Miguel Garrido.)
2546 Paraguay's 2014 DST will be as predicted. (Thanks to Carlos Raúl Perasso.)
2548 Better descriptions of countries with same time zone history as
2549 Trinidad and Tobago since 1970. (Thanks to Alan Barrett for suggestion.)
2551 Several changes affect tz-link.htm, the main web page.
2553 Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
2556 Mention xCal (Internet RFC 6321) and jCal.
2558 Microsoft has some support for tz database names.
2560 CLDR data formats include both XML and JSON.
2562 Mention Maggiolo's map of solar vs standard time.
2563 (Thanks to Arthur David Olson.)
2565 Mention TZ4Net. (Thanks to Matt Johnson.)
2567 Mention the timezone-olson Haskell package.
2569 Mention zeitverschiebung.net. (Thanks to Martin Jäger.)
2571 Remove moribund links to daylight-savings-time.info and to
2572 Simple Timer + Clocks.
2574 Update two links. (Thanks to Oscar van Vlijmen.)
2576 Fix some formatting glitches, e.g., remove random newlines from
2577 abbr elements' title attributes.
2580 Release 2013i - 2013-12-17 07:25:23 -0800
2582 Changes affecting near-future timestamps:
2584 Jordan switches back to standard time at 00:00 on December 20, 2013.
2585 The 2006-2011 transition schedule is planned to resume in 2014.
2586 (Thanks to Steffen Thorsen.)
2588 Changes affecting past timestamps:
2590 In 2004, Cuba began DST on March 28, not April 4.
2591 (Thanks to Steffen Thorsen.)
2593 Changes affecting code
2595 The compile-time flag NOSOLAR has been removed, as nowadays the
2596 benefit of slightly shrinking runtime table size is outweighed by the
2597 cost of disallowing potential future updates that exceed old limits.
2599 Changes affecting documentation and commentary
2601 The files solar87, solar88, and solar89 are no longer distributed.
2602 They were a negative experiment - that is, a demonstration that
2603 tz data can represent solar time only with some difficulty and error.
2604 Their presence in the distribution caused confusion, as Riyadh
2605 civil time was generally not solar time in those years.
2607 tz-link.htm now mentions Noda Time. (Thanks to Matt Johnson.)
2610 Release 2013h - 2013-10-25 15:32:32 -0700
2612 Changes affecting current and future timestamps:
2614 Libya has switched its UT offset back to +02 without DST, instead
2615 of +01 with DST. (Thanks to Even Scharning.)
2617 Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
2618 (Thanks to Gwillim Law.)
2620 Changes affecting future timestamps:
2622 Acre and (we guess) western Amazonas will switch from UT -04 to -05
2623 on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
2624 (Thanks to Steffen Thorsen.)
2626 Add entries for DST transitions in Morocco in the year 2038.
2627 This avoids some year-2038 glitches introduced in 2013g.
2628 (Thanks to Yoshito Umaoka for reporting the problem.)
2630 Changes affecting API
2632 The 'tzselect' command no longer requires the 'select' command,
2633 and should now work with /bin/sh on more platforms. It also works
2634 around a bug in BusyBox awk before version 1.21.0. (Thanks to
2635 Patrick 'P. J.' McDermott and Alan Barrett.)
2637 Changes affecting code
2639 Fix localtime overflow bugs with 32-bit unsigned time_t.
2641 zdump no longer assumes sscanf returns maximal values on overflow.
2643 Changes affecting the build procedure
2645 The builder can specify which programs to use, if any, instead of
2646 'ar' and 'ranlib', and libtz.a is now built locally before being
2647 installed. (Thanks to Michael Forney.)
2649 A dependency typo in the 'zdump' rule has been fixed.
2650 (Thanks to Andrew Paprocki.)
2652 The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
2653 work as specified by POSIX.2-1992 or later; this is portable nowadays.
2655 'make clean' no longer removes 'leapseconds', since it's
2656 host-independent and is part of the distribution.
2658 The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
2660 Changes affecting documentation and commentary
2662 tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
2663 (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
2665 Update URLs in tz-link page. Add URLs for Microsoft Windows, since
2666 8.1 introduces tz support. Remove URLs for Tru64 and UnixWare (no
2667 longer maintained) and for old advisories. SOFA now does C.
2669 Release 2013g - 2013-09-30 21:08:26 -0700
2671 Changes affecting current and near-future timestamps
2673 Morocco now observes DST from the last Sunday in March to the last
2674 Sunday in October, not April to September respectively. (Thanks
2675 to Steffen Thorsen.)
2677 Changes affecting 'zic'
2679 'zic' now runs on platforms that lack both hard links and symlinks.
2680 (Thanks to Theo Veenker for reporting the problem, for MinGW.)
2681 Also, fix some bugs on platforms that lack hard links but have symlinks.
2683 'zic -v' again warns that Asia/Tehran has no POSIX environment variable
2684 to predict the far future, fixing a bug introduced in 2013e.
2686 Changes affecting the build procedure
2688 The 'leapseconds' file is again put into the tzdata tarball.
2689 Also, 'leapseconds.awk', so tzdata is self-contained. (Thanks to
2690 Matt Burgess and Ian Abbott.) The timestamps of these and other
2691 dependent files in tarballs are adjusted more consistently.
2693 Changes affecting documentation and commentary
2695 The README file is now part of the data tarball as well as the code.
2696 It now states that files are public domain unless otherwise specified.
2697 (Thanks to Andrew Main (Zefram) for asking for clarifications.)
2698 Its details about the 1989 release moved to a place of honor near
2702 Release 2013f - 2013-09-24 23:37:36 -0700
2704 Changes affecting near-future timestamps
2706 Tocantins will very likely not observe DST starting this spring.
2707 (Thanks to Steffen Thorsen.)
2709 Jordan will likely stay at UT +03 indefinitely, and will not fall
2712 Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
2714 Changes affecting API
2716 The types of the global variables 'timezone' and 'altzone' (if present)
2717 have been changed back to 'long'. This is required for 'timezone'
2718 by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
2719 These variables were originally 'long' in the tz code, but were
2720 mistakenly changed to 'time_t' in 1987; nobody reported the
2721 incompatibility until now. The difference matters on x32, where
2722 'long' is 32 bits and 'time_t' is 64. (Thanks to Elliott Hughes.)
2724 Changes affecting the build procedure
2726 Avoid long strings in leapseconds.awk to work around a mawk bug.
2727 (Thanks to Cyril Baurand.)
2729 Changes affecting documentation and commentary
2731 New file 'NEWS' that contains release notes like this one.
2733 Paraguay's law does not specify DST transition time; 00:00 is customary.
2734 (Thanks to Waldemar Villamayor-Venialbo.)
2736 Minor capitalization fixes.
2738 Changes affecting version-control only
2740 The experimental GitHub repository now contains annotated and
2741 signed tags for recent releases, e.g., '2013e' for Release 2013e.
2742 Releases are tagged starting with 2012e; earlier releases were
2743 done differently, and tags would either not have a simple name or
2744 not exactly match what was released.
2746 'make set-timestamps' is now simpler and a bit more portable.
2749 Release 2013e - 2013-09-19 23:50:04 -0700
2751 Changes affecting near-future timestamps
2753 This year Fiji will start DST on October 27, not October 20.
2754 (Thanks to David Wheeler for the heads-up.) For now, guess that
2755 Fiji will continue to spring forward the Sunday before the fourth
2758 Changes affecting current and future time zone abbreviations
2760 Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
2761 time zone abbreviations since 1932. (Thanks to George Ziegler,
2762 Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
2763 Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
2764 Asia/Makassar, and Asia/Pontianak.
2766 Use ART (UT -03, standard time), rather than WARST (also -03, but
2767 daylight saving time) for San Luis, Argentina since 2009.
2769 Changes affecting Godthåb timestamps after 2037 if version mismatch
2771 Allow POSIX-like TZ strings where the transition time's hour can
2772 range from -167 through 167, instead of the POSIX-required 0
2773 through 24. E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
2774 new Fiji rules. This is a more-compact way to represent
2775 far-future timestamps for America/Godthab, America/Santiago,
2776 Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
2777 Pacific/Easter, and Pacific/Fiji. Other zones are unaffected by
2778 this change. (Derived from a suggestion by Arthur David Olson.)
2780 Allow POSIX-like TZ strings where daylight saving time is in
2781 effect all year. E.g., TZ='WART4WARST,J1/0,J365/25' for Western
2782 Argentina Summer Time all year. This supports a more-compact way
2783 to represent the 2013d data for America/Argentina/San_Luis.
2784 Because of the change for San Luis noted above this change does not
2785 affect the current data. (Thanks to Andrew Main (Zefram) for
2786 suggestions that improved this change.)
2788 Where these two TZ changes take effect, there is a minor extension
2789 to the tz file format in that it allows new values for the
2790 embedded TZ-format string, and the tz file format version number
2791 has therefore been increased from 2 to 3 as a precaution.
2792 Version-2-based client code should continue to work as before for
2793 all timestamps before 2038. Existing version-2-based client code
2794 (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
2795 files, and typically works in practice even for timestamps after
2796 2037; the only known exception is America/Godthab.
2798 Changes affecting timestamps before 1970
2800 Pacific/Johnston is now a link to Pacific/Honolulu. This corrects
2801 some errors before 1947.
2803 Some zones have been turned into links, when they differ from existing
2804 zones only in older data entries that were likely invented or that
2805 differ only in LMT or transitions from LMT. These changes affect
2806 only timestamps before 1943. The affected zones are:
2807 Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
2808 America/Grenada, America/Guadeloupe, America/Marigot,
2809 America/Montserrat, America/St_Barthelemy, America/St_Kitts,
2810 America/St_Lucia, America/St_Thomas, America/St_Vincent,
2811 America/Tortola, and Europe/Vaduz. (Thanks to Alois Treindl for
2812 confirming that the old Europe/Vaduz zone was wrong and the new
2813 link is better for WWII-era times.)
2815 Change Kingston Mean Time from -5:07:12 to -5:07:11. This affects
2816 America/Cayman, America/Jamaica and America/Grand_Turk timestamps
2819 Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
2820 This affects Europe/Zurich timestamps from 1853 to 1894. (Thanks
2823 Change the date of the circa-1850 Zurich transition from 1849-09-12
2824 to 1853-07-16, overriding Shanks with data from Messerli about
2825 postal and telegraph time in Switzerland.
2827 Changes affecting time zone abbreviations before 1970
2829 For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
2830 as Jakarta was called Batavia back then.
2832 Changes affecting API
2834 The 'zic' command now outputs a dummy transition when far-future
2835 data can't be summarized using a TZ string, and uses a 402-year
2836 window rather than a 400-year window. For the current data, this
2837 affects only the Asia/Tehran file. It does not affect any of the
2838 timestamps that this file represents, so zdump outputs the same
2839 information as before. (Thanks to Andrew Main (Zefram).)
2841 The 'date' command has a new '-r' option, which lets you specify
2842 the integer time to display, a la FreeBSD.
2844 The 'tzselect' command has two new options '-c' and '-n', which lets you
2845 select a zone based on latitude and longitude.
2847 The 'zic' command's '-v' option now warns about constructs that
2848 require the new version-3 binary file format. (Thanks to Arthur
2849 David Olson for the suggestion.)
2851 Support for floating-point time_t has been removed.
2852 It was always dicey, and POSIX no longer requires it.
2853 (Thanks to Eric Blake for suggesting to the POSIX committee to
2854 remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
2855 Heninger, Arthur David Olson, and Alois Treindl, for reporting
2856 bugs and elucidating some of the corners of the old floating-point
2859 The signatures of 'offtime', 'timeoff', and 'gtime' have been
2860 changed back to the old practice of using 'long' to represent UT
2861 offsets. This had been inadvertently and mistakenly changed to
2862 'int_fast32_t'. (Thanks to Christos Zoulas.)
2864 The code avoids undefined behavior on integer overflow in some
2865 more places, including gmtime, localtime, mktime and zdump.
2867 Changes affecting the zdump utility
2869 zdump now outputs "UT" when referring to Universal Time, not "UTC".
2870 "UTC" does not make sense for timestamps that predate the introduction
2871 of UTC, whereas "UT", a more-generic term, does. (Thanks to Steve Allen
2872 for clarifying UT vs UTC.)
2874 Data changes affecting behavior of tzselect and similar programs
2876 Country code BQ is now called the more-common name "Caribbean Netherlands"
2877 rather than the more-official "Bonaire, St Eustatius & Saba".
2879 Remove from zone.tab the names America/Montreal, America/Shiprock,
2880 and Antarctica/South_Pole, as they are equivalent to existing
2881 same-country-code zones for post-1970 timestamps. The data entries for
2882 these names are unchanged, so the names continue to work as before.
2884 Changes affecting code internals
2886 zic -c now runs way faster on 64-bit hosts when given large numbers.
2888 zic now uses vfprintf to avoid allocating and freeing some memory.
2890 tzselect now computes the list of continents from the data,
2891 rather than have it hard-coded.
2893 Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
2895 Changes affecting the build procedure
2897 The 'leapseconds' file is now generated automatically from a
2898 new file 'leap-seconds.list', which is a copy of
2899 <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
2900 A new source file 'leapseconds.awk' implements this.
2901 The goal is simplification of the future maintenance of 'leapseconds'.
2903 When building the 'posix' or 'right' subdirectories, if the
2904 subdirectory would be a copy of the default subdirectory, it is
2905 now made a symbolic link if that is supported. This saves about
2906 2 MB of file system space.
2908 The links America/Shiprock and Antarctica/South_Pole have been
2909 moved to the 'backward' file. This affects only nondefault builds
2910 that omit 'backward'.
2912 Changes affecting version-control only
2914 .gitignore now ignores 'date'.
2916 Changes affecting documentation and commentary
2918 Changes to the 'tzfile' man page
2920 It now mentions that the binary file format may be extended in
2921 future versions by appending data.
2923 It now refers to the 'zdump' and 'zic' man pages.
2925 Changes to the 'zic' man page
2927 It lists conditions that elicit a warning with '-v'.
2929 It says that the behavior is unspecified when duplicate names
2930 are given, or if the source of one link is the target of another.
2932 Its examples are updated to match the latest data.
2934 The definition of white space has been clarified slightly.
2935 (Thanks to Michael Deckers.)
2937 Changes to the 'Theory' file
2939 There is a new section about the accuracy of the tz database,
2940 describing the many ways that errors can creep in, and
2941 explaining why so many of the pre-1970 timestamps are wrong or
2942 misleading (thanks to Steve Allen, Lester Caine, and Garrett
2943 Wollman for discussions that contributed to this).
2945 The 'Theory' file describes LMT better (this follows a
2946 suggestion by Guy Harris).
2948 It refers to the 2013 edition of POSIX rather than the 2004 edition.
2950 It's mentioned that excluding 'backward' should not affect the
2951 other data, and it suggests at least one zone.tab name per
2952 inhabited country (thanks to Stephen Colebourne).
2954 Some longstanding restrictions on names are documented, e.g.,
2955 'America/New_York' precludes 'America/New_York/Bronx'.
2957 It gives more reasons for the 1970 cutoff.
2959 It now mentions which time_t variants are supported, such as
2960 signed integer time_t. (Thanks to Paul Goyette for reporting
2961 typos in an experimental version of this change.)
2963 (Thanks to Philip Newton for correcting typos in these changes.)
2965 Documentation and commentary is more careful to distinguish UT in
2966 general from UTC in particular. (Thanks to Steve Allen.)
2968 Add a better source for the Zurich 1894 transition.
2969 (Thanks to Pierre-Yves Berger.)
2971 Update shapefile citations in tz-link.htm. (Thanks to Guy Harris.)
2974 Release 2013d - 2013-07-05 07:38:01 -0700
2976 Changes affecting future timestamps:
2978 Morocco's midsummer transitions this year are July 7 and August 10,
2979 not July 9 and August 8. (Thanks to Andrew Paprocki.)
2981 Israel now falls back on the last Sunday of October.
2982 (Thanks to Ephraim Silverberg.)
2984 Changes affecting past timestamps:
2986 Specify Jerusalem's location more precisely; this changes the pre-1880
2989 Changing affecting metadata only:
2991 Fix typos in the entries for country codes BQ and SX.
2993 Changes affecting code:
2995 Rework the code to fix a bug with handling Australia/Macquarie on
2996 32-bit hosts (thanks to Arthur David Olson).
2998 Port to platforms like NetBSD, where time_t can be wider than long.
3000 Add support for testing time_t types other than the system's.
3001 Run 'make check_time_t_alternatives' to try this out.
3002 Currently, the tests fail for unsigned time_t;
3003 this should get fixed at some point.
3005 Changes affecting documentation and commentary:
3007 Deemphasize the significance of national borders.
3009 Update the zdump man page.
3011 Remove obsolete NOID comment (thanks to Denis Excoffier).
3013 Update several URLs and comments in the web pages.
3015 Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
3017 Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
3020 Release 2013c - 2013-04-19 16:17:40 -0700
3022 Changes affecting current and future timestamps:
3024 Palestine observed DST starting March 29, 2013. (Thanks to
3025 Steffen Thorsen.) From 2013 on, Gaza and Hebron both observe DST,
3026 with the predicted rules being the last Thursday in March at 24:00
3027 to the first Friday on or after September 21 at 01:00.
3029 Assume that the recent change to Paraguay's DST rules is permanent,
3030 by moving the end of DST to the 4th Sunday in March every year.
3031 (Thanks to Carlos Raúl Perasso.)
3033 Changes affecting past timestamps:
3035 Fix some historical data for Palestine to agree with that of
3036 timeanddate.com, as follows:
3038 The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
3041 The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
3044 The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
3046 The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
3048 The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
3050 The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
3052 Fix times of habitation for Macquarie to agree with the Tasmania
3053 Parks & Wildlife Service history, which indicates that permanent
3054 habitation was 1899-1919 and 1948 on.
3056 Changing affecting metadata only:
3058 Macquarie Island is politically part of Australia, not Antarctica.
3059 (Thanks to Tobias Conradi.)
3061 Sort Macquarie more-consistently with other parts of Australia.
3062 (Thanks to Tim Parenti.)
3065 Release 2013b - 2013-03-10 22:33:40 -0700
3067 Changes affecting current and future timestamps:
3069 Haiti uses US daylight-saving rules this year, and presumably future years.
3070 This changes timestamps starting today. (Thanks to Steffen Thorsen.)
3072 Paraguay will end DST on March 24 this year.
3073 (Thanks to Steffen Thorsen.) For now, assume it's just this year.
3075 Morocco does not observe DST during Ramadan;
3076 try to predict Ramadan in Morocco as best we can.
3077 (Thanks to Erik Homoet for the heads-up.)
3079 Changes affecting commentary:
3081 Update URLs in tz-link page. Add URLs for webOS, BB10, iOS.
3082 Update URL for Solaris. Mention Internet RFC 6557.
3083 Update Internet RFCs 2445->5545, 2822->5322.
3084 Switch from FTP to HTTP for Internet RFCs.
3087 Release 2013a - 2013-02-27 09:20:35 -0800
3089 Change affecting binary data format:
3091 The zone offset at the end of version-2-format zone files is now
3092 allowed to be 24:00, as per POSIX.1-2008. (Thanks to Arthur David Olson.)
3094 Changes affecting current and future timestamps:
3096 Chile's 2013 rules, and we guess rules for 2014 and later, will be
3097 the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
3098 (Thanks to Steffen Thorsen and Robert Elz.)
3100 New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
3101 (Thanks to Tobias Conradi and Arthur David Olson.)
3103 Many changes affect historical timestamps before 1940.
3104 These were deduced from: Milne J. Civil time. Geogr J. 1899
3105 Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
3107 Changes affecting the code:
3109 Fix zic bug that mishandled Egypt's 2010 changes (this also affected
3110 the data). (Thanks to Arthur David Olson.)
3112 Fix localtime bug when time_t is unsigned and data files were generated
3113 by a signed time_t system. (Thanks to Doug Bailey for reporting and
3114 to Arthur David Olson for fixing.)
3116 Allow the email address for bug reports to be set by the packager.
3117 The default is tz@iana.org, as before. (Thanks to Joseph S. Myers.)
3119 Update HTML checking to be compatible with Ubuntu 12.10.
3121 Check that files are a safe subset of ASCII. At some point we may
3122 relax this requirement to a safe subset of UTF-8. Without the
3123 check, some non-UTF-8 encodings were leaking into the distribution.
3127 Restore a comment about copyright notices that was inadvertently deleted.
3128 (Thanks to Arthur David Olson.)
3130 Improve the commentary about which districts observe what times
3131 in Russia. (Thanks to Oscar van Vlijmen and Arthur David Olson.)
3133 Add web page links to tz.js.
3135 Add "Run by the Monkeys" to tz-art. (Thanks to Arthur David Olson.)
3138 Release 2012j - 2012-11-12 18:34:49 -0800
3140 Libya moved to CET this weekend, but with DST planned next year.
3141 (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
3143 Signatures now have the extension .asc, not .sign, as that's more
3144 standard. (Thanks to Phil Pennock.)
3146 The output of 'zdump --version', and of 'zic --version', now
3147 uses a format that is more typical for --version.
3148 (Thanks to Joseph S. Myers.)
3150 The output of 'tzselect --help', 'zdump --help', and 'zic --help'
3151 now uses tz@iana.org rather than the old elsie address.
3153 zic -v now complains about abbreviations that are less than 3
3154 or more than 6 characters, as per Posix. Formerly, it checked
3155 for abbreviations that were more than 3.
3157 'make public' no longer puts its temporary directory under /tmp,
3158 and uses the just-built zic rather than the system zic.
3160 Various fixes to documentation and commentary.
3163 Release 2012i - 2012-11-03 12:57:09 -0700
3165 Cuba switches from DST tomorrow at 01:00. (Thanks to Steffen Thorsen.)
3167 Linker flags can now be specified via LDFLAGS.
3168 AWK now defaults to 'awk', not 'nawk'.
3169 The shell in tzselect now defaults to /bin/bash, but this can
3170 be overridden by specifying KSHELL.
3171 The main web page now mentions the unofficial GitHub repository.
3172 (Thanks to Mike Frysinger.)
3174 Tarball signatures can now be built by running 'make signatures'.
3175 There are also new makefile rules 'tarballs', 'check_public', and
3176 separate makefile rules for each tarball and signature file.
3177 A few makefile rules are now more portable to strict POSIX.
3179 The main web page now lists the canonical IANA URL.
3182 Release 2012h - 2012-10-26 22:49:10 -0700
3184 Bahia no longer has DST. (Thanks to Kelley Cook.)
3186 Tocantins has DST. (Thanks to Rodrigo Severo.)
3188 Israel has new DST rules next year. (Thanks to Ephraim Silverberg.)
3190 Jordan stays on DST this winter. (Thanks to Steffen Thorsen.)
3194 More C modernization, except that at Arthur David Olson's suggestion
3195 the instances of 'register' were kept.
3198 Release 2012g - 2012-10-17 20:59:45 -0700
3200 Samoa fall 2012 and later. (Thanks to Nicholas Pereira and Robert Elz.)
3202 Palestine fall 2012. (Thanks to Steffen Thorsen.)
3206 To attack the version-number problem, this release ships the file
3207 'Makefile' (which contains the release number) in both the tzcode and
3208 the tzdata tarballs. The two Makefiles are identical, and should be
3209 identical in any matching pair of tarballs, so it shouldn't matter
3210 which order you extract the tarballs. Perhaps we can come up with a
3211 better version-number scheme at some point; this scheme does have the
3212 virtue of not adding more files.
3215 Release 2012f - 2012-09-12 23:17:03 -0700
3217 * australasia (Pacific/Fiji): Fiji DST is October 21 through January
3218 20 this year. (Thanks to Steffen Thorsen.)
3221 Release 2012e - 2012-08-02 20:44:55 -0700
3223 * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
3224 (Thanks to Steffen Thorsen.)
3226 * Use a single version number for both code and data.
3228 * .gitignore: New file.
3230 * Remove trailing white space.
3233 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
3235 Changes for Morocco's timestamps, which take effect in a couple of
3236 hours, along with infrastructure changes to accommodate how the tz
3237 code and data are released on IANA.
3240 Release data2012c - 2012-03-27 12:17:25 -0400
3243 Summer time changes for Morocco (to start late April 2012)
3246 Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
3249 Haiti following US/Canada rules for 2012 (and we're assuming,
3250 for now anyway, for the future).
3253 Release 2012b - 2012-03-02 12:29:15 +0700
3255 There is just one change to tzcode2012b (compared with 2012a):
3256 the Makefile that was accidentally included with 2012a has been
3257 replaced with the version that should have been there, which is
3258 identical with the previous version (from tzcode2011i).
3260 There are just two changes in tzdata2012b compared with 2012a.
3262 Most significantly, summer time in Cuba has been delayed 3 weeks
3263 (now starts April 1 rather than March 11). Since Mar 11 (the old start
3264 date, as listed in 2012a) is just a little over a week away, this
3267 Less importantly, an excess tab in one of the changes in zone.tab
3268 in 2012a has been removed.
3271 Release 2012a - 2012-03-01 18:28:10 +0700
3273 The changes in tzcode2012a (compared to the previous version, 2011i)
3274 are entirely to the README and tz-art.htm and tz-link.htm files, if
3275 none of those concern you, you can ignore the code update. The changes
3276 reflect the changed addresses for the mailing list and the code and
3277 data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
3278 has been added to tz-link.htm).
3280 In tzdata2012a (compared to the previous release, which was 2011n)
3281 the major changes are:
3282 Chile 2011/2012 and 2012/2013 summer time date adjustments.
3283 Falkland Islands onto permanent summer time (we're assuming for the
3284 foreseeable future, though 2012 is all we're fairly certain of.)
3285 Armenia has abolished Summer Time.
3286 Tokelau jumped the International Date Line back last December
3287 (just the same as their near neighbour, Samoa).
3288 America/Creston is a new zone for a small area of British Columbia
3289 There will be a leapsecond 2012-06-30 23:59:60 UTC.
3291 Other minor changes are:
3292 Corrections to 1918 Canadian summer time end dates.
3293 Updated URL for UK time zone history (in comments)
3294 A few typos in Le Corre's list of free French place names (comments)
3297 Release data2011n - 2011-10-30 14:57:54 +0700
3299 There are three changes of note - most urgently, Cuba (America/Havana)
3300 has extended summer time by two weeks, now to end on Nov 13, rather than
3301 the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic
3302 (Europe/Tiraspol) decided not to split from the rest of Moldova after
3303 all, and consequently that zone has been removed (again) and reinstated
3304 in the "backward" file as a link to Europe/Chisinau. And third, the
3305 end date for Fiji's summer time this summer was moved forward from the
3306 earlier planned Feb 26, to Jan 22.
3308 Apart from that, Moldova (MD) returns to a single entry in zone.tab
3309 (and the incorrect syntax that was in the 2011m version of that file
3310 is so fixed - it would have been fixed in a different way had this
3311 change not happened - that's the "missing" sccs version id).
3314 Release data2011m - 2011-10-24 21:42:16 +0700
3316 In particular, the typos in comments in the data (2011-11-17 should have
3317 been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
3318 Tim Parenti noted) have been fixed, and the change for Ukraine has been
3319 made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
3320 Tim Parenti, and also Denys Gavrysh)
3322 In addition, I added Europe/Tiraspol to zone.tab.
3324 This time, all the files have new version numbers... (including the files
3325 otherwise unchanged in 2011m that were changed in 2011l but didn't get new
3326 version numbers there...)
3329 Release data2011l - 2011-10-10 11:15:43 +0700
3331 There are just 2 changes that cause different generated tzdata files from
3332 zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
3333 is included, but commented out. Compared with the diff I sent out last week,
3334 this version also includes attributions for the sources for the changes
3335 (in much the same format as ado used, but the html tags have not been
3336 checked, verified, or used in any way at all, so if there are errors there,
3337 please let me know.)
3340 Release data2011k - 2011-09-20 17:54:03 -0400
3345 Release data2011j - 2011-09-12 09:22:49 -0400
3347 (contemporary changes for Samoa; past changes for Kenya, Uganda, and
3348 Tanzania); there are also two spelling corrections to comments in
3349 the australasia file (with thanks to Christos Zoulas).
3352 Release 2011i - 2011-08-29 05:56:32 -0400
3357 Release data2011h - 2011-06-15 18:41:48 -0400
3359 Russia and Curaçao changes
3362 Release 2011g - 2011-04-25 09:07:22 -0400
3364 update the rules for Egypt to reflect its abandonment of DST this year
3367 Release 2011f - 2011-04-06 17:14:53 -0400
3372 Release 2011e - 2011-03-31 16:04:38 -0400
3374 Morocco, Chile, and tz-link changes
3377 Release 2011d - 2011-03-14 09:18:01 -0400
3379 changes that impact present-day timestamps in Cuba, Samoa, and Turkey
3382 Release 2011c - 2011-03-07 09:30:09 -0500
3384 These do affect current timestamps in Chile and Annette Island, Canada.
3387 Release 2011b - 2011-02-07 08:44:50 -0500
3392 Release 2011a - 2011-01-24 10:30:16 -0500
3397 Release data2010o - 2010-11-01 09:18:23 -0400
3399 change to the end of DST in Fiji in 2011
3402 Release 2010n - 2010-10-25 08:19:17 -0400
3407 Release 2010m - 2010-09-27 09:24:48 -0400
3409 Hong Kong, Vostok, and zic.c changes
3412 Release 2010l - 2010-08-16 06:57:25 -0400
3417 Release 2010k - 2010-07-26 10:42:27 -0400
3422 Release 2010j - 2010-05-10 09:07:48 -0400
3424 changes for Bahía de Banderas and for version naming
3427 Release data2010i - 2010-04-16 18:50:45 -0400
3429 the end of DST in Morocco on 2010-08-08
3432 Release data2010h - 2010-04-05 09:58:56 -0400
3437 Release data2010g - 2010-03-24 11:14:53 -0400
3442 Release 2010f - 2010-03-22 09:45:46 -0400
3447 Release data2010e - 2010-03-08 14:24:27 -0500
3449 corrects the Dhaka bug found by Danvin Ruangchan
3452 Release data2010d - 2010-03-06 07:26:01 -0500
3457 Release 2010c - 2010-03-01 09:20:58 -0500
3459 changes including KRE's suggestion for earlier initialization of
3460 "goahead" and "goback" structure elements
3463 Release code2010a - 2010-02-16 10:40:04 -0500
3468 Release data2010b - 2010-01-20 12:37:01 -0500
3473 Release data2010a - 2010-01-18 08:30:04 -0500
3478 Release data2009u - 2009-12-26 08:32:28 -0500
3480 changes to DST in Bangladesh
3483 Release 2009t - 2009-12-21 13:24:27 -0500
3488 Release data2009s - 2009-11-14 10:26:32 -0500
3490 (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
3493 Release 2009r - 2009-11-09 10:10:31 -0500
3495 "antarctica" and "tz-link.htm" changes
3498 Release 2009q - 2009-11-02 09:12:40 -0500
3500 with two corrections as reported by Eric Muller and Philip Newton
3503 Release data2009p - 2009-10-23 15:05:27 -0400
3505 Argentina (including San Luis) changes (with the correction from
3509 Release data2009o - 2009-10-14 16:49:38 -0400
3511 Samoa (commentary only), Pakistan, and Bangladesh changes
3514 Release data2009n - 2009-09-22 15:13:38 -0400
3516 added commentary for Argentina and a change to the end of DST in
3520 Release data2009m - 2009-09-03 10:23:43 -0400
3522 Samoa and Palestine changes
3525 Release data2009l - 2009-08-14 09:13:07 -0400
3527 Samoa (comments only) and Egypt
3530 Release 2009k - 2009-07-20 09:46:08 -0400
3535 Release data2009j - 2009-06-15 06:43:59 -0400
3537 Bangladesh change (with a short turnaround since the DST change is
3541 Release 2009i - 2009-06-08 09:21:22 -0400
3543 updating for DST in Bangladesh this year
3546 Release 2009h - 2009-05-26 09:19:14 -0400
3551 Release data2009g - 2009-04-20 16:34:07 -0400
3556 Release data2009f - 2009-04-10 11:00:52 -0400
3558 correct DST in Pakistan
3561 Release 2009e - 2009-04-06 09:08:11 -0400
3566 Release 2009d - 2009-03-23 09:38:12 -0400
3568 Morocco, Tunisia, Argentina, and American Astronomical Society changes
3571 Release data2009c - 2009-03-16 09:47:51 -0400
3573 change to the start of Cuban DST
3576 Release 2009b - 2009-02-09 11:15:22 -0500
3581 Release 2009a - 2009-01-21 10:09:39 -0500
3586 Release data2008i - 2008-10-21 12:10:25 -0400
3588 southamerica and zone.tab files, with Argentina DST rule changes and
3589 United States zone reordering and recommenting
3592 Release 2008h - 2008-10-13 07:33:56 -0400
3597 Release 2008g - 2008-10-06 09:03:18 -0400
3599 Fix a broken HTML anchor and update Brazil's DST transitions;
3600 there's also a slight reordering of information in tz-art.htm.
3603 Release data2008f - 2008-09-09 22:33:26 -0400
3608 Release 2008e - 2008-07-28 14:11:17 -0400
3610 changes by Arthur David Olson and Jesper Nørgaard Welen
3613 Release data2008d - 2008-07-07 09:51:38 -0400
3615 changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
3618 Release data2008c - 2008-05-19 17:48:03 -0400
3620 Pakistan, Morocco, and Mongolia
3623 Release data2008b - 2008-03-24 08:30:59 -0400
3625 including renaming Asia/Calcutta to Asia/Kolkata, with a backward
3629 Release 2008a - 2008-03-08 05:42:16 -0500
3634 Release 2007k - 2007-12-31 10:25:22 -0500
3636 most importantly, changes to the "southamerica" file based on
3637 Argentina's readoption of daylight saving time
3640 Release 2007j - 2007-12-03 09:51:01 -0500
3642 1. eliminate the "P" (parameter) macro;
3644 2. the "noncontroversial" changes circulated on the time zone
3645 mailing list (less the changes to "logwtmp.c");
3647 3. eliminate "too many transition" errors when "min" is used in time
3650 4. changes by Paul Eggert (including updated information for Venezuela).
3653 Release data2007i - 2007-10-30 10:28:11 -0400
3655 changes for Cuba and Syria
3658 Release 2007h - 2007-10-01 10:05:51 -0400
3660 changes by Paul Eggert, as well as an updated link to the ICU
3661 project in tz-link.htm
3664 Release 2007g - 2007-08-20 10:47:59 -0400
3666 changes by Paul Eggert
3668 The "leapseconds" file has been updated to incorporate the most
3669 recent International Earth Rotation and Reference Systems Service
3672 There's an addition to tz-art.htm regarding the television show "Medium".
3675 Release 2007f - 2007-05-07 10:46:46 -0400
3677 changes by Paul Eggert (including Haiti, Turks and Caicos, and New
3680 changes to zic.c to allow hour values greater than 24 (along with
3681 Paul's improved time value overflow checking)
3684 Release 2007e - 2007-04-02 10:11:52 -0400
3686 Syria and Honduras changes by Paul Eggert
3688 zic.c variable renaming changes by Arthur David Olson
3691 Release 2007d - 2007-03-20 08:48:30 -0400
3693 changes by Paul Eggert
3695 the elimination of white space at the ends of lines
3698 Release 2007c - 2007-02-26 09:09:37 -0500
3700 changes by Paul Eggert
3703 Release 2007b - 2007-02-12 09:34:20 -0500
3705 Paul Eggert's proposed change to the quotation handling logic in zic.c.
3707 changes to the commentary in "leapseconds" reflecting the IERS
3708 announcement that there is to be no positive leap second at the end
3712 Release 2007a - 2007-01-08 12:28:29 -0500
3714 changes by Paul Eggert
3716 Derick Rethan's Asmara change
3718 Oscar van Vlijmen's Easter Island local mean time change
3720 symbolic link changes
3723 Release 2006p - 2006-11-27 08:54:27 -0500
3725 changes by Paul Eggert
3728 Release 2006o - 2006-11-06 09:18:07 -0500
3730 changes by Paul Eggert
3733 Release 2006n - 2006-10-10 11:32:06 -0400
3735 changes by Paul Eggert
3738 Release 2006m - 2006-10-02 15:32:35 -0400
3740 changes for Uruguay, Palestine, and Egypt by Paul Eggert
3742 (minimalist) changes to zic.8 to clarify "until" information
3745 Release data2006l - 2006-09-18 12:58:11 -0400
3747 Paul's best-effort work on this coming weekend's Egypt time change
3750 Release 2006k - 2006-08-28 12:19:09 -0400
3752 changes by Paul Eggert
3755 Release 2006j - 2006-08-21 09:56:32 -0400
3757 changes by Paul Eggert
3760 Release code2006i - 2006-08-07 12:30:55 -0400
3764 Ken Pizzini's conversion script
3767 Release code2006h - 2006-07-24 09:19:37 -0400
3769 adds public domain notices to four files
3771 includes a fix for transition times being off by a second
3773 adds a new recording to the "arts" file (information courtesy Colin Bowern)
3776 Release 2006g - 2006-05-08 17:18:09 -0400
3778 northamerica changes by Paul Eggert
3781 Release 2006f - 2006-05-01 11:46:00 -0400
3783 a missing version number problem is fixed (with thanks to Bradley
3784 White for catching the problem)
3787 Release 2006d - 2006-04-17 14:33:43 -0400
3789 changes by Paul Eggert
3791 added new items to tz-arts.htm that were found by Paul
3794 Release 2006c - 2006-04-03 10:09:32 -0400
3796 two sets of data changes by Paul Eggert
3798 a fencepost error fix in zic.c
3800 changes to zic.c and the "europe" file to minimize differences
3801 between output produced by the old 32-bit zic and the new 64-bit
3805 Release 2006b - 2006-02-20 10:08:18 -0500
3806 [tz32code2006b + tz64code2006b + tzdata2006b]
3810 All SCCS IDs were bumped to "8.1" for this release.
3813 Release 2006a - 2006-01-30 08:59:31 -0500
3815 changes by Paul Eggert (in particular, Indiana time zone moves)
3817 an addition to the zic manual page to describe how special-case
3818 transitions are handled
3821 Release 2005r - 2005-12-27 09:27:13 -0500
3823 Canadian changes by Paul Eggert
3825 They also add "<pre>" directives to time zone data files and reflect
3826 changes to warning message logic in "zdump.c" (but with calls to
3827 "gettext" kept unbundled at the suggestion of Ken Pizzini).
3830 Release 2005q - 2005-12-13 09:17:09 -0500
3832 Nothing earth-shaking here:
3833 1. Electronic mail addresses have been removed.
3834 2. Casts of the return value of exit have been removed.
3835 3. Casts of the argument of is.* macros have been added.
3836 4. Indentation in one section of zic.c has been fixed.
3837 5. References to dead URLs in the data files have been dealt with.
3840 Release 2005p - 2005-12-05 10:30:53 -0500
3842 "systemv", "tz-link.htm", and "zdump.c" changes
3843 (less the casts of arguments to the is* macros)
3846 Release 2005o - 2005-11-28 10:55:26 -0500
3848 Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
3850 zdump.c lint fixes by Arthur David Olson
3853 Release 2005n - 2005-10-03 09:44:09 -0400
3855 changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
3859 Release 2005m - 2005-08-29 12:15:40 -0400
3861 changes by Paul Eggert (with a small tweak to the tz-art change)
3863 a declaration of an unused variable has been removed from zdump.c
3866 Release 2005l - 2005-08-22 12:06:39 -0400
3868 changes by Paul Eggert
3870 overflow/underflow checks by Arthur David Olson, minus changes to
3871 the "Theory" file about the pending addition of 64-bit data (I grow
3872 less confident of the changes being accepted with each passing day,
3873 and the changes no longer increase the data files nine-fold--there's
3874 less than a doubling in size by my local Sun's reckoning)
3877 Release 2005k - 2005-07-14 14:14:24 -0400
3879 The "leapseconds" file has been edited to reflect the recently
3880 announced leap second at the end of 2005.
3882 I've also deleted electronic mail addresses from the files as an
3886 Release 2005j - 2005-06-13 14:34:13 -0400
3888 These reflect changes to limit the length of time zone abbreviations
3889 and the characters used in those abbreviations.
3891 There are also changes to handle POSIX-style "quoted" timezone
3892 environment variables.
3894 The changes were circulated on the time zone mailing list; the only
3895 change since then was the removal of a couple of minimum-length of
3896 abbreviation checks.
3899 Release data2005i - 2005-04-21 15:04:16 -0400
3901 changes (most importantly to Nicaragua and Haiti) by Paul Eggert
3904 Release 2005h - 2005-04-04 11:24:47 -0400
3906 changes by Paul Eggert
3908 minor changes to Makefile and zdump.c to produce more useful output
3909 when doing a "make typecheck"
3912 Release 2005g - 2005-03-14 10:11:21 -0500
3914 changes by Paul Eggert (a change to current DST rules in Uruguay and
3915 an update to a link to time zone software)
3918 Release 2005f - 2005-03-01 08:45:32 -0500
3920 data and documentation changes by Paul Eggert
3923 Release 2005e - 2005-02-10 15:59:44 -0500
3928 Release code2005d - 2005-01-31 09:21:47 -0500
3930 make zic complain about links to links if the -v flag is used
3932 have "make public" do more code checking
3934 add an include to "localtime.c" for the benefit of gcc systems
3937 Release 2005c - 2005-01-17 18:36:29 -0500
3939 get better results when mktime runs on a system where time_t is double
3941 changes to the data files (most importantly to Paraguay)
3944 Release 2005b - 2005-01-10 09:19:54 -0500
3946 Get localtime and gmtime working on systems with exotic time_t types.
3948 Update the leap second commentary in the "leapseconds" file.
3951 Release 2005a - 2005-01-01 13:13:44 -0500
3956 Release code2004i - 2004-12-14 13:42:58 -0500
3958 Deal with systems where time_t is unsigned.
3961 Release code2004h - 2004-12-07 11:40:18 -0500
3963 64-bit-time_t changes
3966 Release 2004g - 2004-11-02 09:06:01 -0500
3968 update to Cuba (taking effect this weekend)
3970 other changes by Paul Eggert
3972 correction of the spelling of Oslo
3974 changed versions of difftime.c and private.h
3977 Release code2004f - 2004-10-21 10:25:22 -0400
3979 Cope with wide-ranging tm_year values.
3982 Release 2004e - 2004-10-11 14:47:21 -0400
3984 Brazil/Argentina/Israel changes by Paul Eggert
3986 changes to tz-link.htm by Paul
3988 one small fix to Makefile
3991 Release 2004d - 2004-09-22 08:27:29 -0400
3993 Avoid overflow problems when TM_YEAR_BASE is added to an integer.
3996 Release 2004c - 2004-08-11 12:06:26 -0400
3998 asctime-related changes
4000 (variants of) some of the documentation changes suggested by Paul Eggert
4003 Release 2004b - 2004-07-19 14:33:35 -0400
4005 data changes by Paul Eggert - most importantly, updates for Argentina
4008 Release 2004a - 2004-05-27 12:00:47 -0400
4010 changes by Paul Eggert
4012 Handle DST transitions that occur at the end of a month in some
4013 years but at the start of the following month in other years.
4015 Add a copy of the correspondence that's the basis for claims about
4016 DST in the Navajo Nation.
4019 Release 2003e - 2003-12-15 09:36:47 -0500
4021 changes by Arthur David Olson (primarily code changes)
4023 changes by Paul Eggert (primarily data changes)
4025 minor changes to "Makefile" and "northamerica" (in the latter case,
4026 optimization of the "Toronto" rules)
4029 Release 2003d - 2003-10-06 09:34:44 -0400
4031 changes by Paul Eggert
4034 Release 2003c - 2003-09-16 10:47:05 -0400
4036 Fix bad returns in zic.c's inleap function.
4037 Thanks to Bradley White for catching the problem!
4040 Release 2003b - 2003-09-16 07:13:44 -0400
4042 Add a "--version" option (and documentation) to the zic and zdump commands.
4044 changes to overflow/underflow checking in zic
4046 a localtime typo fix.
4048 Update the leapseconds and tz-art.htm files.
4051 Release 2003a - 2003-03-24 09:30:54 -0500
4053 changes by Paul Eggert
4055 a few additions and modifications to the tz-art.htm file
4058 Release 2002d - 2002-10-15 13:12:42 -0400
4060 changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
4062 There's also a new time zone quote in "tz-art.htm".
4065 Release 2002c - 2002-04-04 11:55:20 -0500
4067 changes by Paul Eggert
4069 Change zic.c to avoid creating symlinks to files that don't exist.
4072 Release 2002b - 2002-01-28 12:56:03 -0500
4074 [These change notes are for Release 2002a, which was corrupted.
4075 2002b was a corrected version of 2002a.]
4077 changes by Paul Eggert
4079 Update the "leapseconds" file to note that there'll be no leap
4080 second at the end of June, 2002.
4082 Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
4084 Change to "difftime.c" to avoid sizeof problems.
4087 Release 2001d - 2001-10-09 13:31:32 -0400
4089 changes by Paul Eggert
4092 Release 2001c - 2001-06-05 13:59:55 -0400
4094 changes by Paul Eggert and Andrew Brown
4097 Release 2001b - 2001-04-05 16:44:38 -0400
4099 changes by Paul Eggert (modulo jnorgard's typo fix)
4101 tz-art.htm has been HTMLified.
4104 Release 2001a - 2001-03-13 12:57:44 -0500
4106 changes by Paul Eggert
4108 An addition to the "leapseconds" file: comments with the text of the
4109 latest IERS leap second notice.
4111 Trailing white space has been removed from data file lines, and
4112 repeated spaces in "Rule Jordan" lines in the "asia" file have been
4116 Release 2000h - 2000-12-14 15:33:38 -0500
4118 changes by Paul Eggert
4120 one typo fix in the "art" file
4122 With providence, this is the last update of the millennium.
4125 Release 2000g - 2000-10-10 11:35:22 -0400
4127 changes by Paul Eggert
4129 correction of John Mackin's name submitted by Robert Elz
4131 Garry Shandling's Daylight Saving Time joke (!?!) from the recent
4132 Emmy Awards broadcast.
4135 Release 2000f - 2000-08-10 09:31:58 -0400
4137 changes by Paul Eggert
4139 Added information in "tz-art.htm" on a Seinfeld reference to DST.
4141 Error checking and messages in the "yearistype" script have been
4145 Release 2000e - 2000-07-31 09:27:54 -0400
4147 data changes by Paul Eggert
4149 a change to the default value of the defined constant HAVE_STRERROR
4151 the addition of a Dave Barry quote on DST to the tz-arts file
4154 Release 2000d - 2000-04-20 15:43:04 -0400
4156 changes to the documentation and code of strftime for C99 conformance
4158 a bug fix for date.c
4160 These are based on (though modified from) changes by Paul Eggert.
4163 Release 2000c - 2000-03-04 10:31:43 -0500
4165 changes by Paul Eggert
4168 Release 2000b - 2000-02-21 12:16:29 -0500
4170 changes by Paul Eggert and Joseph Myers
4172 modest tweaks to the tz-art.htm and tz-link.htm files
4175 Release 2000a - 2000-01-18 09:21:26 -0500
4177 changes by Paul Eggert
4179 The two hypertext documents have also been renamed.
4182 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
4184 Paul Eggert's changes
4186 additions to the "zic" manual page and the "Arts.htm" file
4189 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
4194 Release data1999h - 1999-10-07 03:50:29 -0400
4196 changes by Paul Eggert to "europe" (most importantly, fixing
4197 Lithuania and Estonia)
4200 Release 1999g - 1999-09-28 11:06:18 -0400
4202 data changes by Paul Eggert (most importantly, the change for
4203 Lebanon that buys correctness for this coming Sunday)
4205 The "code" file contains changes to "Makefile" and "checktab.awk" to
4206 allow better checking of time zone files before they are published.
4209 Release 1999f - 1999-09-23 09:48:14 -0400
4211 changes by Arthur David Olson and Paul Eggert
4214 Release 1999e - 1999-08-17 15:20:54 -0400
4216 changes circulated by Paul Eggert, although the change to handling
4217 of DST-specifying timezone names has been commented out for now
4218 (search for "XXX" in "localtime.c" for details). These files also
4219 do not make any changes to the start of DST in Brazil.
4221 In addition to Paul's changes, there are updates to "Arts.htm" and
4225 Release 1999d - 1999-03-30 11:31:07 -0500
4227 changes by Paul Eggert
4229 The Makefile's "make public" rule has also been changed to do a test
4230 compile of each individual time zone data file (which should help
4231 avoid problems such as the one we had with Nicosia).
4234 Release 1999c - 1999-03-25 09:47:47 -0500
4236 changes by Paul Eggert, most importantly the change for Chile.
4239 Release 1999b - 1999-02-01 17:51:44 -0500
4241 changes by Paul Eggert
4243 code changes (suggested by Mani Varadarajan, mani at be.com) for
4244 correct handling of symbolic links when building using a relative directory
4246 code changes to generate correct messages for failed links
4248 updates to the URLs in Arts.htm
4251 Release 1999a - 1999-01-19 16:20:29 -0500
4253 error message internationalizations and corrections in zic.c and
4254 zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
4258 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
4260 changes for Brazil, Chile, and Germany
4262 support for use of "24:00" in the input files for the time zone compiler
4265 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
4267 changes by Paul Eggert
4269 correction to a define in the "private.h" file
4272 Release data1998g - 1998-08-11 03:28:35 -0000
4273 [tzdata1998g.tar.gz is missing!]
4275 Lithuanian change provided by mgedmin at pub.osf.it
4277 Move creation of the GMT link with Etc/GMT to "etcetera" (from
4278 "backward") to ensure that the GMT file is created even where folks
4279 don't want the "backward" links (as suggested by Paul Eggert).
4282 Release data1998f - 1998-07-20 13:50:00 -0000
4283 [tzdata1998f.tar.gz is missing!]
4285 Update the "leapseconds" file to include the newly-announced
4286 insertion at the end of 1998.
4289 Release code1998f - 1998-06-01 10:18:31 -0400
4291 addition to localtime.c by Guy Harris
4294 Release 1998e - 1998-05-28 09:56:26 -0400
4296 The Makefile is changed to produce zoneinfo-posix rather than
4297 zoneinfo/posix, and to produce zoneinfo-leaps rather than
4300 data changes by Paul Eggert
4302 changes from Guy Harris to provide asctime_r and ctime_r
4304 A usno1998 file (substantially identical to usno1997) has been added.
4307 Release 1998d - 1998-05-14 11:58:34 -0400
4309 changes to comments (in particular, elimination of references to CIA maps).
4310 "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
4311 where changes occur.
4314 Release 1998c - 1998-02-28 12:32:26 -0500
4316 changes by Paul Eggert (save the "French correction," on which I'll
4317 wait for the dust to settle)
4321 changes and additions to Arts.htm
4324 Release 1998b - 1998-01-17 14:31:51 -0500
4326 URL cleanups and additions
4329 Release 1998a - 1998-01-13 12:37:35 -0500
4331 changes by Paul Eggert
4334 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
4336 changes by Paul Eggert, with minor modifications from Arthur David
4337 Olson to make the files more browser friendly
4340 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
4342 minor changes to put "TZif" at the start of each timezone information file
4344 a rule has also been added to the Makefile so you can
4346 to just recompile the zone information files (rather than doing a
4347 full "make install" with its other effects).
4350 Release data1997i - 1997-10-07 08:45:38 -0400
4352 changes to Africa by Paul Eggert
4355 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
4357 corrections for Uruguay (and other locations)
4359 Arthur David Olson's simple-minded fix allowing mktime to both
4360 correctly handle leap seconds and correctly handle tm_sec values
4361 upon which arithmetic has been performed.
4364 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
4366 Paul Eggert's updates
4368 a small change to a function prototype;
4370 "Music" has been renamed "Arts.htm", HTMLified, and augmented to
4371 include information on Around the World in Eighty Days.
4374 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
4376 fixes to zic's error handling
4378 changes inspired by the item circulated on Slovenia
4380 The description of Web resources has been HTMLified for browsing
4383 A new piece of tz-related music has been added to the "Music" file.
4386 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
4388 Paul Eggert's latest suggestions
4391 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
4393 changes to "zic.c" to correct performance of the "-s" option
4395 a new file "usno1997"
4398 Release data1997c - 1997-03-04 09:58:18 -0500
4403 Release 1997b - 1997-02-27 18:34:19 -0500
4405 The data file incorporates the 1997 leap second.
4407 The code file incorporates Arthur David Olson's take on the
4408 zic/multiprocessor/directory-creation situation.
4411 Release 1997a - 1997-01-21 09:11:10 -0500
4413 Paul Eggert's Antarctica (and other changes)
4415 Arthur David Olson finessed the "getopt" issue by checking against
4416 both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
4417 is returned while SunOS 5.5's manual says EOF is returned).
4420 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
4422 Paul Eggert's latest changes
4425 Release code1996n - 1996-12-16 09:42:02 -0500
4427 link snapping fix from Bruce Evans (via Garrett Wollman)
4430 Release data1996m - 1996-11-24 02:37:34 -0000
4431 [tzdata1996m.tar.gz is missing!]
4433 Paul Eggert's batch of changes
4436 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
4438 No functional changes here; the files have simply been changed to
4439 make more use of ISO style dates in comments. The names of the above
4440 files now include the year in full.
4443 Release code96l - 1996-09-08 17:12:20 -0400
4445 tzcode96k was missing a couple of pieces.
4448 Release 96k - 1996-09-08 16:06:22 -0400
4450 the latest round of changes from Paul Eggert
4452 the recent Year 2000 material
4455 Release code96j - 1996-07-30 13:18:53 -0400
4457 Set sp->typecnt as suggested by Timothy Patrick Murphy.
4460 Release code96i - 1996-07-27 20:11:35 -0400
4462 Paul's suggested patch for strftime %V week numbers
4465 Release data96i - 1996-07-01 18:13:04 -0400
4467 "northamerica" and "europe" changes by Paul Eggert
4470 Release code96h - 1996-06-05 08:02:21 -0400
4472 fix for handling transitions specified in Universal Time
4474 Some "public domain" notices have also been added.
4477 Release code96g - 1996-05-16 14:00:26 -0400
4479 fix for the simultaneous-DST-and-zone-change challenge
4482 Release data96h - 1996-05-09 17:40:51 -0400
4484 changes by Paul Eggert
4487 Release code96f-data96g - 1996-05-03 03:09:59 -0000
4488 [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
4490 The changes get us some of the way to fixing the problems noted in Paul
4491 Eggert's letter yesterday (in addition to a few others). The approach
4492 has been to make zic a bit smarter about figuring out what time zone
4493 abbreviations apply just after the time specified in the "UNTIL" part
4494 of a zone line. Putting the smarts in zic means avoiding having
4495 transition times show up in both "Zone" lines and "Rule" lines, which
4496 in turn avoids multiple transition time entries in time zone files.
4497 (This also makes the zic input files such as "europe" a bit shorter and
4498 should ease maintenance.)
4501 Release data96f - 1996-04-19 19:20:03 -0000
4502 [tzdata96f.tar.gz is missing!]
4504 The only changes are to the "northamerica" file; the time zone
4505 abbreviation for Denver is corrected to MST (and MDT), and the
4506 comments for Mexico have been updated.
4509 Release data96e - 1996-03-19 17:37:26 -0500
4511 Proposals by Paul Eggert, in particular the Portugal change that
4512 comes into play at the end of this month.
4515 Release data96d - 1996-03-18 20:49:39 -0500
4520 Release code96e - 1996-02-29 15:43:27 -0000
4521 [tzcode96e.tar.gz is missing!]
4523 internationalization changes and the fix to the documentation for strftime
4526 Release code96d-data96c - 1996-02-12 11:05:27 -0500
4528 The "code" file simply updates Bob Kridle's electronic address.
4530 The "data" file updates rules for Mexico.
4533 Release data96b - 1996-01-27 15:44:42 -0500
4538 Release code96c - 1996-01-16 16:58:15 -0500
4540 leap-year streamlining and binary-search changes
4545 Release code96b - 1996-01-10 20:42:39 -0500
4547 fixes and enhancements from Paul Eggert, including code that
4548 emulates the behavior of recent versions of the SunOS "date"
4552 Release 96a - 1996-01-06 09:08:24 -0500
4556 fixes to strftime.c for correct ISO 8601 week number generation,
4557 plus support for two new formats ('G' and 'g') to give ISO 8601 year
4558 numbers (which are not necessarily the same as calendar year numbers)
4561 Release code95i-data95m - 1995-12-21 12:46:47 -0500
4563 The latest revisions from Paul Eggert are included, the usno1995
4564 file has been updated, and a new file ("WWW") covering useful URLs
4568 Release code95h-data95l - 1995-12-19 18:10:12 -0500
4570 A simplification of a macro definition, a change to data for Sudan,
4571 and (for last minute shoppers) notes in the "Music" file on the CD
4575 Release code95g-data95k - 1995-10-30 10:32:47 -0500
4577 (slightly reformatted) 8-bit-clean proposed patch
4579 minor patch: US/Eastern -> America/New_York
4581 snapshot of the USNO's latest data ("usno1995")
4583 some other minor cleanups
4586 Release code95f-data95j - 1995-10-28 21:01:34 -0000
4587 [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
4591 support for 64-bit time_t's
4593 optimization in localtime.c
4596 Release code95e - 1995-10-13 13:23:57 -0400
4598 the mktime change to scan from future to past when trying to find time zone
4602 Release data95i - 1995-09-26 10:43:26 -0400
4604 For Canada/Central, guess that the Sun customer's "one week too
4605 early" was just a approximation, and the true error is one month
4606 too early. This is consistent with the rest of Canada.
4609 Release data95h - 1995-09-21 11:26:48 -0400
4611 latest changes from Paul Eggert
4614 Release code95d - 1995-09-14 11:14:45 -0400
4616 the addition of a "Music" file, which documents four recorded
4617 versions of the tune "Save That Time".
4620 Release data95g - 1995-09-01 17:21:36 -0400
4622 "yearistype" correction
4625 Release data95f - 1995-08-28 20:46:56 -0400
4627 Paul Eggert's change to the australasia file
4630 Release data95e - 1995-07-08 18:02:34 -0400
4632 The only change is a leap second at the end of this year.
4633 Thanks to Bradley White for forwarding news on the leap second.
4636 Release data95d - 1995-07-03 13:26:22 -0400
4638 Paul Eggert's changes
4641 Release data95c - 1995-07-02 19:19:28 -0400
4643 changes to "asia", "backward", "europe", and "southamerica"
4644 (read: northamericacentrics need not apply)
4647 Release code95c - 1995-03-13 14:00:46 -0500
4649 one-line fix for sign extension problems in detzcode
4652 Release 95b - 1995-03-04 11:22:38 -0500
4654 Minor changes in both:
4656 The "code" file contains a workaround for the lack of "unistd.h" in
4657 Microsoft C++ version 7.
4659 The "data" file contains a fixed "Link" for America/Shiprock.
4662 Release 94h - 1994-12-10 12:51:14 -0500
4666 * incorporate the changes to "zdump" and "date" to make changes to
4667 the "TZ" environment variable permanent;
4669 * incorporate the table changes by Paul Eggert;
4671 * include (and document) support for universal time specifications in
4672 data files - but do not (yet) include use of this feature in the
4675 Think of this as "TZ Classic" - the software has been set up not to break if
4676 universal time shows up in its input, and data entries have been
4677 left as is so as not to break existing implementations.
4680 Release data94f - 1994-08-20 12:56:09 -0400
4682 (with thanks!) the latest data updates from Paul Eggert
4685 Release data94e - 1994-06-04 13:13:53 -0400
4690 Release code94g - 1994-05-05 12:14:07 -0400
4692 fix missing "optind.c" and a reference to it in the Makefile
4695 Release code94f - 1994-05-05 13:00:33 -0000
4696 [tzcode94f.tar.gz is missing!]
4698 changes to avoid overflow in difftime, as well as changes to cope
4699 with the 52/53 challenge in strftime
4702 Release code94e - 1994-03-30 23:32:59 -0500
4704 change for the benefit of PCTS
4707 Release 94d - 1994-02-24 15:42:25 -0500
4709 Avoid clashes with POSIX semantics for zones such as GMT+4.
4711 Some other very minor housekeeping is also present.
4714 Release code94c - 1994-02-10 08:52:40 -0500
4716 Fix bug where mkdirs was broken unless you compile with
4717 -fwritable-strings (which is generally losing to do).
4720 Release 94b - 1994-02-07 10:04:33 -0500
4722 work by Paul Eggert who notes:
4724 I found another book of time zone histories by E W Whitman; it's not
4725 as extensive as Shanks but has a few goodies of its own. I used it
4726 to update the tables. I also fixed some more as a result of
4727 correspondence with Adam David and Peter Ilieve, and move some stray
4728 links from 'europe' to 'backward'. I corrected some scanning errors
4731 As far as the code goes, I fixed zic to allow years in the range
4732 INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
4733 And I cleaned up the zic documentation a little bit.
4736 Release data94a - 1994-02-03 08:58:54 -0500
4738 It simply incorporates the recently announced leap second into the
4742 Release 93g - 1993-11-22 17:28:27 -0500
4744 Paul Eggert has provided a good deal of historic information (based
4745 on Shanks), and there are some code changes to deal with the buglets
4746 that crawled out in dealing with the new information.
4749 Release 93f - 1993-10-15 12:27:46 -0400
4751 Paul Eggert's changes
4754 Release 93e - 1993-09-05 21:21:44 -0400
4756 This has updated data for Israel, England, and Kwajalein. There's
4757 also an update to "zdump" to cope with Kwajalein's 24-hour jump.
4758 Thanks to Paul Eggert and Peter Ilieve for the changes.
4761 Release 93d - 1993-06-17 23:34:17 -0400
4763 new fix and new data on Israel
4766 Release 93c - 1993-06-06 19:31:55 -0400
4771 Release 93b - 1993-02-02 14:53:58 -0500
4773 updated "leapseconds" file
4776 Release 93 - 1993-01-08 07:01:06 -0500
4778 At kre's suggestion, the package has been split in two - a code piece
4779 (which also includes documentation) that's only of use to folks who
4780 want to recompile things and a data piece useful to anyone who can
4783 The new version has a few changes to the data files, a few
4784 portability changes, and an off-by-one fix (with thanks to
4785 Tom Karzes at deshaw.com for providing a description and a
4789 Release 92c - 1992-11-21 17:35:36 -0000
4790 [tz92c.tar.Z is missing!]
4792 The fallout from the latest round of DST transitions.
4794 There are changes for Portugal, Saskatchewan, and "Pacific-New";
4795 there's also a change to "zic.c" that makes it portable to more systems.
4798 Release 92 - 1992-04-25 18:17:03 -0000
4799 [tz92.tar.Z is missing!]
4801 By popular demand (well, at any rate, following a request by kre at munnari)
4804 The 1989 update of the time zone package featured:
4806 * POSIXization (including interpretation of POSIX-style TZ environment
4807 variables, provided by Guy Harris),
4808 * ANSIfication (including versions of "mktime" and "difftime"),
4809 * SVIDulation (an "altzone" variable)
4810 * MACHination (the "gtime" function)
4811 * corrections to some time zone data (including corrections to the rules
4812 for Great Britain and New Zealand)
4813 * reference data from the United States Naval Observatory for folks who
4814 want to do additional time zones
4815 * and the 1989 data for Saudi Arabia.
4817 (Since this code will be treated as "part of the implementation" in some
4818 places and as "part of the application" in others, there's no good way to
4819 name functions, such as timegm, that are not part of the proposed ANSI C
4820 standard; such functions have kept their old, underscore-free names in this
4823 And the "dysize" function has disappeared; it was present to allow
4824 compilation of the "date" command on old BSD systems, and a version of "date"
4825 is now provided in the package. The "date" command is not created when you
4826 "make all" since it may lack options provided by the version distributed with
4827 your operating system, or may not interact with the system in the same way
4828 the native version does.
4830 Since POSIX frowns on correct leap second handling, the default behavior of
4831 the "zic" command (in the absence of a "-L" option) has been changed to omit
4832 leap second information from its output files.
4838 This file contains copies of the part of each release announcement
4839 that talks about the changes in that release. The text has been
4840 adapted and reformatted for the purposes of this file.
4842 Traditionally a release R consists of a pair of tarball files,
4843 tzcodeR.tar.gz and tzdataR.tar.gz. However, some releases (e.g.,
4844 code2010a, data2012c) consist of just one or the other tarball, and a
4845 few (e.g., code2012c-data2012d) have tarballs with mixed version
4846 numbers. Recent releases also come in an experimental format
4847 consisting of a single tarball tzdb-R.tar.lz with extra data.
4849 Release timestamps are taken from the release's commit (for newer,
4850 Git-based releases), from the newest file in the tarball (for older
4851 releases, where this info is available) or from the email announcing
4852 the release (if all else fails; these are marked with a time zone
4853 abbreviation of -0000 and an "is missing!" comment).
4855 Earlier versions of the code and data were not announced on the tz
4856 list and are not summarized here.
4858 This file is in the public domain.