1 News for the tz database
3 Release 2018g - 2018-10-26 22:22:45 -0700
6 Morocco switches to permanent +01 on 2018-10-27.
8 Changes to future timestamps
10 Morocco switches from +00/+01 to permanent +01 effective 2018-10-27,
11 so its clocks will not fall back on 2018-10-28 as previously scheduled.
12 (Thanks to Mohamed Essedik Najd and Brian Inglis.)
16 When generating TZif files with leap seconds, zic no longer uses a
17 format that trips up older 32-bit clients, fixing a bug introduced
18 in 2018f. (Reported by Daniel Fischer.) Also, the zic workaround
19 for QTBUG-53071 now also works for TZif files with leap seconds.
21 The translator to rearguard format now rewrites the line
22 "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
23 "Rule Japan 1948 1951 - Sep Sun>=9 1:00 0 S".
24 This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
25 and earlier. (Reported by Christos Zoulas.)
27 Changes to past time zone abbreviations
29 Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
30 This reverts to 2011h, as the abbreviation change in 2011i was
33 Changes to documentation
35 tzfile.5 has new sections on interoperability issues.
38 Release 2018f - 2018-10-18 00:14:18 -0700
41 Volgograd moves from +03 to +04 on 2018-10-28.
42 Fiji ends DST 2019-01-13, not 2019-01-20.
43 Most of Chile changes DST dates, effective 2019-04-06.
45 Changes to future timestamps
47 Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
48 (Thanks to Alexander Fetisov and Stepan Golosunov.)
50 Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
51 predicted. (Thanks to Raymond Kumar.) Adjust future predictions
54 Most of Chile will end DST on the first Saturday in April at 24:00 mainland
55 time, and resume DST on the first Saturday in September at 24:00 mainland
56 time. The changes are effective from 2019-04-06, and do not affect the
57 Magallanes region modeled by America/Punta_Arenas. (Thanks to Juan Correa
58 and Tim Parenti.) Adjust future predictions accordingly.
60 Changes to past timestamps
62 The 2018-05-05 North Korea 30-minute time zone change took place
63 at 23:30 the previous day, not at 00:00 that day.
65 China's 1988 spring-forward transition was on April 17, not
66 April 10. Its DST transitions in 1986/91 were at 02:00, not 00:00.
69 Fix several issues for Macau before 1992. Macau's pre-1904 LMT
70 was off by 10 s. Macau switched to +08 in 1904 not 1912, and
71 temporarily switched to +09/+10 during World War II. Macau
72 observed DST in 1942/79, not 1961/80, and there were several
73 errors for transition times and dates. (Thanks to P Chan.)
75 The 1948-1951 fallback transitions in Japan were at 25:00 on
76 September's second Saturday, not at 24:00. (Thanks to Phake Nick.)
77 zic turns this into 01:00 on the day after September's second
78 Saturday, which is the best that POSIX or C platforms can do.
80 Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
81 paper by Li Yu, replacing more-questionable data from Shanks.
83 Changes to time zone abbreviations
85 Use "PST" and "PDT" for Philippine time. (Thanks to Paul Goyette.)
89 zic now always generates TZif files where time type 0 is used for
90 timestamps before the first transition. This simplifies the
91 reading of TZif files and should not affect behavior of existing
92 TZif readers because the same set of time types is used; only
93 their internal indexes may have changed. This affects only the
94 legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
95 EET, which previously used nonzero types for these timestamps.
97 Because of the type 0 change, zic no longer outputs a dummy
98 transition at time -2**59 (before the Big Bang), as clients should
99 no longer need this to handle historical timestamps correctly.
100 This reverts a change introduced in 2013d and shrinks most TZif
101 files by a few bytes.
103 zic now supports negative time-of-day in Rule and Leap lines, e.g.,
104 "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
105 occurs at 18:00 on the Saturday before the last Sunday in April.
106 This behavior was documented in 2018a but the code did not
107 entirely match the documentation.
109 localtime.c no longer requires at least one time type in TZif
110 files that lack transitions or have a POSIX-style TZ string. This
111 future-proofs the code against possible future extensions to the
112 format that would allow TZif files with POSIX-style TZ strings and
113 without transitions or time types.
115 A read-access subscript error in localtime.c has been fixed.
116 It could occur only in TZif files with timecnt == 0, something that
117 does not happen in practice now but could happen in future versions.
119 localtime.c no longer ignores TZif POSIX-style TZ strings that
120 specify only standard time. Instead, these TZ strings now
121 override the default time type for timestamps after the last
122 transition (or for all time stamps if there are no transitions),
123 just as DST strings specifying DST have always done.
125 leapseconds.awk now outputs "#updated" and "#expires" comments,
126 and supports leap seconds at the ends of months other than June
127 and December. (Inspired by suggestions from Chris Woodbury.)
129 Changes to documentation
131 New restrictions: A Rule name must start with a character that
132 is neither an ASCII digit nor "-" nor "+", and an unquoted name
133 should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
134 The latter restriction makes room for future extensions (a
135 possibility noted by Tom Lane).
137 tzfile.5 now documents what time types apply before the first and
138 after the last transition, if any.
140 Documentation now uses the spelling "timezone" for a TZ setting
141 that determines timestamp history, and "time zone" for a
142 geographic region currently sharing the same standard time.
144 The name "TZif" is now used for the tz binary data format.
146 tz-link.htm now mentions the A0 TimeZone Migration utilities.
147 (Thanks to Aldrin Martoq for the link.)
149 Changes to build procedure
151 New 'make' target 'rearguard_tarballs' to build the rearguard
152 tarball only. This is a convenience on platforms that lack lzip
153 if you want to build the rearguard tarball. (Problem reported by
156 tzdata.zi is now more stable from release to release. (Problem
157 noted by Tom Lane.) It is also a bit shorter.
159 tzdata.zi now can contain comment lines documenting configuration
160 information, such as which data format was selected, which input
161 files were used, and how leap seconds are treated. (Problems
162 noted by Lester Caine and Brian Inglis.) If the Makefile defaults
163 are used these comment lines are absent, for backward
164 compatibility. A redistributor intending to alter its copy of the
165 files should also append "-LABEL" to the 'version' file's first
166 line, where "LABEL" identifies the redistributor's change.
169 Release 2018e - 2018-05-01 23:42:51 -0700
173 North Korea switches back to +09 on 2018-05-05.
174 The main format uses negative DST again, for Ireland etc.
175 'make tarballs' now also builds a rearguard tarball.
176 New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
178 Changes to past and future timestamps
180 North Korea switches back from +0830 to +09 on 2018-05-05.
181 (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
184 Bring back the negative-DST changes of 2018a, except be more
185 compatible with data parsers that do not support negative DST.
186 Also, this now affects historical timestamps in Namibia and the
187 former Czechoslovakia, not just Ireland. The main format now uses
188 negative DST to model timestamps in Europe/Dublin (from 1971 on),
189 Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This
190 does not affect UT offsets, only time zone abbreviations and the
191 tm_isdst flag. Also, this does not affect rearguard or vanguard
192 formats; effectively the main format now uses vanguard instead of
193 rearguard format. Data parsers that do not support negative DST
194 can still use data from the rearguard tarball described below.
196 Changes to build procedure
198 The command 'make tarballs' now also builds the tarball
199 tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
200 except that it uses rearguard format intended for trailing-edge
203 Changes to data format and to code
205 The SAVE column of Rule and Zone lines can now have an 's' or 'd'
206 suffix, which specifies whether the adjusted time is standard time
207 or daylight saving time. If no suffix is given, daylight saving
208 time is used if and only if the SAVE column is nonzero; this is
209 the longstanding behavior. Although this new feature is not used
210 in tzdata, it could be used to specify the legal time in Namibia
211 1994-2017, as opposed to the popular time (see below).
213 Changes to past timestamps
215 From 1994 through 2017 Namibia observed DST in winter, not summer.
216 That is, it used negative DST, as Ireland still does. This change
217 does not affect UTC offsets; it affects only the tm_isdst flag and
218 the abbreviation used during summer, which is now CAT, not WAST.
219 Although (as noted by Michael Deckers) summer and winter time were
220 both simply called "standard time" in Namibian law, in common
221 practice winter time was considered to be DST (as noted by Stephen
222 Colebourne). The full effect of this change is only in vanguard
223 and main format; in rearguard format, the tm_isdst flag is still
224 zero in winter and nonzero in summer.
226 In 1946/7 Czechoslovakia also observed negative DST in winter.
227 The full effect of this change is only in vanguard and main
228 formats; in rearguard format, it is modeled as plain GMT without
229 daylight saving. Also, the dates of some 1944/5 DST transitions
230 in Czechoslovakia have been changed.
233 Release 2018d - 2018-03-22 07:05:46 -0700
237 Palestine starts DST a week earlier in 2018.
238 Add support for vanguard and rearguard data consumers.
239 Add subsecond precision to source data format, though not to data.
241 Changes to future timestamps
243 In 2018, Palestine starts DST on March 24, not March 31.
244 Adjust future predictions accordingly. (Thanks to Sharef Mustafa.)
246 Changes to past and future timestamps
248 Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
249 at 04:00. (Thanks to Steffen Thorsen.)
251 Changes to past timestamps
253 Historical transitions for Uruguay, represented by
254 America/Montevideo, have been updated per official legal documents,
255 replacing previous data mainly originating from the inventions of
256 Shanks & Pottenger. This has resulted in adjustments ranging from
257 30 to 90 minutes in either direction over at least two dozen
258 distinct periods ranging from one day to several years in length.
259 A mere handful of pre-1991 transitions are unaffected; data since
260 then has come from more reliable contemporaneous reporting. These
261 changes affect various timestamps in 1920-1923, 1936, 1939,
262 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
263 Additionally, Uruguay's pre-standard-time UT offset has been
264 adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
265 match the location of the Observatory of the National Meteorological
266 Institute in Montevideo.
267 (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
269 Enderbury and Kiritimati skipped New Year's Eve 1994, not
270 New Year's Day 1995. (Thanks to Kerry Shetline.)
272 Fix the 1912-01-01 transition for Portugal and its colonies.
273 This transition was at 00:00 according to the new UT offset, not
274 according to the old one. Also assume that Cape Verde switched on
275 the same date as the rest, not in 1907. This affects
276 Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
277 Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
278 (Thanks to Michael Deckers.)
280 Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
283 Changes to past time zone abbreviations
285 MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There
286 is no clock change associated with the transition.
288 Changes to build procedure
290 The new DATAFORM macro in the Makefile lets the installer choose
291 among three source data formats. The idea is to lessen downstream
292 disruption when data formats are improved.
294 * DATAFORM=vanguard installs from the latest, bleeding-edge
295 format. DATAFORM=main (the default) installs from the format
296 used in the 'africa' etc. files. DATAFORM=rearguard installs
297 from a trailing-edge format. Eventually, elements of today's
298 vanguard format should move to the main format, and similarly
299 the main format's features should eventually move to the
302 * In the current version, the main and rearguard formats are
303 identical and match that of 2018c, so this change does not
304 affect default behavior. The vanguard format currently contains
305 one feature not in the main format: negative SAVE values. This
306 improves support for Ireland, which uses Irish Standard Time
307 (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has
308 supported negative SAVE values for decades, and this feature
309 should move to the main format soon. However, it will not move
310 to the rearguard format for quite some time because some
311 downstream parsers do not support it.
313 * The build procedure constructs three files vanguard.zi, main.zi,
314 and rearguard.zi, one for each format. The files represent the
315 same data as closely as the formats allow. These three files
316 are intended for downstream data consumers and are not
317 installed. Zoneinfo parsers that do not support negative SAVE values
318 should start using rearguard.zi, so that they will be unaffected
319 when the negative-DST feature moves from vanguard to main.
320 Bleeding-edge Zoneinfo parsers that support the new features
321 already can use vanguard.zi; in this respect, current tzcode is
324 The Makefile should now be safe for parallelized builds, and 'make
325 -j to2050new.tzs' is now much faster on a multiprocessor host
328 When built with -DSUPPRESS_TZDIR, the tzcode library no longer
329 prepends TZDIR/ to file names that do not begin with '/'. This is
330 not recommended for general use, due to its security implications.
331 (From a suggestion by Manuela Friedrich.)
335 zic now accepts subsecond precision in expressions like
336 00:19:32.13, which is approximately the legal time of the
337 Netherlands from 1835 to 1937. However, because it is
338 questionable whether the few recorded uses of non-integer offsets
339 had subsecond precision in practice, there are no plans for tzdata
340 to use this feature. (Thanks to Steve Allen for pointing out
341 the limitations of historical data in this area.)
343 The code is a bit more portable to MS-Windows. Installers can
344 compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
345 reserve identifiers like 'localtime'. (Thanks to Manuela
348 Changes to documentation and commentary
350 theory.html now outlines tzdb's extensions to POSIX's model for
351 civil time, and has a section "POSIX features no longer needed"
352 that lists POSIX API components that are now vestigial.
353 (From suggestions by Steve Summit.) It also better distinguishes
354 time zones from tz regions. (From a suggestion by Guy Harris.)
356 Commentary is now more consistent about using the phrase "daylight
357 saving time", to match the C name tm_isdst. Daylight saving time
358 need not occur in summer, and need not have a positive offset from
361 Commentary about historical transitions in Uruguay has been expanded
362 with links to many relevant legal documents.
363 (Thanks to Tim Parenti.)
365 Commentary now uses some non-ASCII characters with Unicode value
366 less than U+0100, as they can be useful and should work even with
367 older editors such as XEmacs.
370 Release 2018c - 2018-01-22 23:00:44 -0800
373 Revert Irish changes that relied on negative SAVE values.
377 Revert the 2018a change to Europe/Dublin. As before, this change
378 does not affect UT offsets or abbreviations; it affects only
379 whether timestamps are considered to be standard time or
380 daylight-saving time, as expressed in the tm_isdst flag of C's
381 struct tm type. This reversion is intended to be a temporary
382 workaround for problems discovered with downstream uses of
383 releases 2018a and 2018b, which implemented Irish time by using
384 negative SAVE values in the Eire rules of the 'europe' file.
385 Although negative SAVE values have been part of tzcode for many
386 years and are supported by many platforms, they were not
387 documented before 2018a and ICU and OpenJDK do not currently
388 support them. A mechanism to export data to platforms lacking
389 support for negative DST is planned to be developed before the
390 change is reapplied. (Problems reported by Deborah Goldsmith and
393 Changes to past timestamps
395 Japanese DST transitions (1948-1951) were Sundays at 00:00, not
396 Saturdays or Sundays at 02:00. (Thanks to Takayuki Nikai.)
398 Changes to build procedure
400 The build procedure now works around mawk 1.3.3's lack of support
401 for character class expressions. (Problem reported by Ohyama.)
404 Release 2018b - 2018-01-17 23:24:48 -0800
407 Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
409 Changes to build procedure
411 The distribution now contains the file 'pacificnew' again.
412 This file was inadvertantly omitted in the 2018a distribution.
413 (Problem reported by Matias Fonzo.)
416 Release 2018a - 2018-01-12 22:29:21 -0800
419 São Tomé and Príncipe switched from +00 to +01.
420 Brazil's DST will now start on November's first Sunday.
421 Ireland's standard time is now in the summer, not the winter.
422 Use Debian-style installation locations, instead of 4.3BSD-style.
425 Changes to past and future timestamps
427 São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
428 01:00. (Thanks to Steffen Thorsen and Michael Deckers.)
430 Changes to future timestamps
432 Starting in 2018 southern Brazil will begin DST on November's
433 first Sunday instead of October's third Sunday. (Thanks to
436 Changes to past timestamps
438 A discrepancy of 4 s in timestamps before 1931 in South Sudan has
439 been corrected. The 'backzone' and 'zone.tab' files did not agree
440 with the 'africa' and 'zone1970.tab' files. (Problem reported by
443 The abbreviation invented for Bolivia Summer Time (1931-2) is now
444 BST instead of BOST, to be more consistent with the convention
445 used for Latvian Summer Time (1918-9) and for British Summer Time.
449 Change Europe/Dublin so that it observes Irish Standard Time (UT
450 +01) in summer and GMT (as negative daylight-saving) in winter,
451 instead of observing standard time (GMT) in winter and Irish
452 Summer Time (UT +01) in summer. This change does not affect UT
453 offsets or abbreviations; it affects only whether timestamps are
454 considered to be standard time or daylight-saving time, as
455 expressed in the tm_isdst flag of C's struct tm type.
456 (Discrepancy noted by Derick Rethans.)
458 Changes to build procedure
460 The default installation locations have been changed to mostly
461 match Debian circa 2017, instead of being designed as an add-on to
462 4.3BSD circa 1986. This affects the Makefile macros TOPDIR,
463 TZDIR, MANDIR, and LIBDIR. New Makefile macros TZDEFAULT, USRDIR,
464 USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
465 locations more precisely. (This responds to suggestions from
466 Brian Inglis and from Steve Summit.)
468 The default installation procedure no longer creates the
469 backward-compatibility link US/Pacific-New, which causes
470 confusion during user setup (e.g., see Debian bug 815200).
471 Use 'make BACKWARD="backward pacificnew"' to create the link
472 anyway, for now. Eventually we plan to remove the link entirely.
474 tzdata.zi now contains a version-number comment.
475 (Suggested by Tom Lane.)
477 The Makefile now quotes values like BACKWARD more carefully when
478 passing them to the shell. (Problem reported by Zefram.)
480 Builders no longer need to specify -DHAVE_SNPRINTF on platforms
481 that have snprintf and use pre-C99 compilers. (Problem reported
486 zic has a new option -t FILE that specifies the location of the
487 file that determines local time when TZ is unset. The default for
488 this location can be configured via the new TZDEFAULT makefile
489 macro, which defaults to /etc/localtime.
491 Diagnostics and commentary now distinguish UT from UTC more
492 carefully; see theory.html for more information about UT vs UTC.
494 zic has been ported to GCC 8's -Wstringop-truncation option.
495 (Problem reported by Martin Sebor.)
497 Changes to documentation and commentary
499 The zic man page now documents the longstanding behavior that
500 times and years can be out of the usual range, with negative times
501 counting backwards from midnight and with year 0 preceding year 1.
502 (Problem reported by Michael Deckers.)
504 The theory.html file now mentions the POSIX limit of six chars
505 per abbreviation, and lists alphabetic abbreviations used.
507 The files tz-art.htm and tz-link.htm have been renamed to
508 tz-art.html and tz-link.html, respectively, for consistency with
509 other file names and to simplify web server configuration.
512 Release 2017c - 2017-10-20 14:49:34 -0700
515 Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
516 Fiji ends DST 2018-01-14, not 2018-01-21.
517 Namibia switches from +01/+02 to +02 on 2018-04-01.
518 Sudan switches from +03 to +02 on 2017-11-01.
519 Tonga likely switches from +13/+14 to +13 on 2017-11-05.
520 Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
521 A new file tzdata.zi now holds a small text copy of all data.
522 The zic input format has been regularized slightly.
524 Changes to future timestamps
526 Northern Cyprus has decided to resume EU rules starting
527 2017-10-29, thus reinstituting winter time.
529 Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
530 predicted. (Thanks to Dominic Fok.) Adjust future predictions
533 Namibia will switch from +01 with DST to +02 all year on
534 2017-09-03 at 02:00. This affects UT offsets starting 2018-04-01
535 at 02:00. (Thanks to Steffen Thorsen.)
537 Sudan will switch from +03 to +02 on 2017-11-01. (Thanks to Ahmed
538 Atyya and Yahia Abdalla.) South Sudan is not switching, so
539 Africa/Juba is no longer a link to Africa/Khartoum.
541 Tonga has likely ended its experiment with DST, and will not
542 adjust its clocks on 2017-11-05. Although Tonga has not announced
543 whether it will continue to observe DST, the IATA is assuming that
544 it will not. (Thanks to David Wade.)
546 Turks & Caicos will switch from -04 all year to -05 with US DST on
547 2018-03-11 at 03:00. This affects UT offsets starting 2018-11-04
548 at 02:00. (Thanks to Steffen Thorsen.)
550 Changes to past timestamps
552 Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
553 (Thanks to Arthur David Olson.)
555 Detroit did not observe DST in 1967.
557 Use railway time for Asia/Kolkata before 1941, by switching to
558 Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
559 1906. Also, treat 1941-2's +0630 as DST, like 1942-5.
561 Europe/Dublin's 1946 and 1947 fallback transitions occurred at
562 02:00 standard time, not 02:00 DST. (Thanks to Michael Deckers.)
564 Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
565 American time in 1892, not 1879. (Thanks to Michael Deckers.)
567 Adjust the 1867 transition in Alaska to better reflect the
568 historical record, by changing it to occur on 1867-10-18 at 15:30
569 Sitka time rather than at the start of 1867-10-17 local time.
570 Although strictly speaking this is accurate only for Sitka,
571 the rest of Alaska's blanks need to be filled in somehow.
573 Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
574 (Thanks to Michael Deckers.)
576 Add 7 s to the UT offset in Asia/Yangon before 1920.
578 Changes to zone names
580 Remove Canada/East-Saskatchewan from the 'backward' file, as it
581 exceeded the 14-character limit and was an unused misnomer anyway.
583 Changes to build procedure
585 To support applications that prefer to read time zone data in text
586 form, two zic input files tzdata.zi and leapseconds are now
587 installed by default. The commands 'zic tzdata.zi' and 'zic -L
588 leapseconds tzdata.zi' can reproduce the tzdata binary files
589 without and with leap seconds, respectively. To prevent these two
590 new files from being installed, use 'make TZDATA_TEXT=', and to
591 suppress leap seconds from the tzdata text installation, use 'make
592 TZDATA_TEXT=tzdata.zi'.
594 'make BACKWARD=' now suppresses backward-compatibility names
595 like 'US/Pacific' that are defined in the 'backward' and
598 'make check' now works on systems that lack a UTF-8 locale,
599 or that lack the nsgmls program. Set UTF8_LOCALE to configure
600 the name of a UTF-8 locale, if you have one.
602 Y2K runtime checks are no longer enabled by default. Add
603 -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
604 adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
605 to disable them. (New name suggested by Brian Inglis.)
607 The build procedure for zdump now works on AIX 7.1.
608 (Problem reported by Kees Dekker.)
612 zic and the reference runtime now reject multiple leap seconds
613 within 28 days of each other, or leap seconds before the Epoch.
614 As a result, support for double leap seconds, which was
615 obsolescent and undocumented, has been removed. Double leap
616 seconds were an error in the C89 standard; they have never existed
617 in civil timekeeping. (Thanks to Robert Elz and Bradley White for
618 noticing glitches in the code that uncovered this problem.)
620 zic now warns about use of the obsolescent and undocumented -y
621 option, and about use of the obsolescent TYPE field of Rule lines.
623 zic now allows unambiguous abbreviations like "Sa" and "Su" for
624 weekdays; formerly it rejected them due to a bug. Conversely, zic
625 no longer considers non-prefixes to be abbreviations; for example,
626 it no longer accepts "lF" as an abbreviation for "lastFriday".
627 Also, zic warns about the undocumented usage with a "last-"
628 prefix, e.g., "last-Fri".
630 Similarly, zic now accepts the unambiguous abbreviation "L" for
631 "Link" in ordinary context and for "Leap" in leap-second context.
632 Conversely, zic no longer accepts non-prefixes such as "La" as
633 abbreviations for words like "Leap".
635 zic no longer accepts leap second lines in ordinary input, or
636 ordinary lines in leap second input. Formerly, zic sometimes
637 warned about this undocumented usage and handled it incorrectly.
639 The new macro HAVE_TZNAME governs whether the tzname external
640 variable is exported, instead of USG_COMPAT. USG_COMPAT now
641 governs only the external variables "timezone" and "daylight".
642 This change is needed because the three variables are not in the
643 same category: although POSIX requires tzname, it specifies the
644 other two variables as optional. Also, USG_COMPAT is now 1 or 0:
645 if not defined, the code attempts to guess it from other macros.
647 localtime.c and difftime.c no longer require stdio.h, and .c files
648 other than zic.c no longer require sys/wait.h.
650 zdump.c no longer assumes snprintf. (Reported by Jonathan Leffler.)
652 Calculation of time_t extrema works around a bug in GCC 4.8.4
653 (Reported by Stan Shebs and Joseph Myers.)
655 zic.c no longer mistranslates formats of line numbers in non-English
656 locales. (Problem reported by Benno Schulenberg.)
658 Several minor changes have been made to the code to make it a
659 bit easier to port to MS-Windows and Solaris. (Thanks to Kees
660 Dekker for reporting the problems.)
662 Changes to documentation and commentary
664 The two new files 'theory.html' and 'calendars' contain the
665 contents of the removed file 'Theory'. The goal is to document
666 tzdb theory more accessibly.
668 The zic man page now documents abbreviation rules.
670 tz-link.htm now covers how to apply tzdata changes to clients.
671 (Thanks to Jorge Fábregas for the AIX link.) It also mentions MySQL.
673 The leap-seconds.list URL has been updated to something that is
674 more reliable for tzdb. (Thanks to Tim Parenti and Brian Inglis.)
676 Release 2017b - 2017-03-17 07:30:38 -0700
678 Briefly: Haiti has resumed DST.
680 Changes to past and future timestamps
682 Haiti resumed observance of DST in 2017. (Thanks to Steffen Thorsen.)
684 Changes to past timestamps
686 Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
688 Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
689 is one byte over the POSIX limit. (Problem reported by Derick Rethans.)
693 The reference localtime implementation now falls back on the
694 current US daylight-saving transition rules rather than the
695 1987-2006 rules. This fallback occurs only when (1) the TZ
696 environment variable has a value like "AST4ADT" that asks
697 for daylight saving time but does not specify the rules, (2) there
698 is no file by that name, and (3) the TZDEFRULES file cannot be
699 loaded. (Thanks to Tom Lane.)
702 Release 2017a - 2017-02-28 00:05:36 -0800
704 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
707 Changes to future timestamps
709 Mongolia no longer observes DST. (Thanks to Ganbold Tsagaankhuu.)
711 Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
712 Its clocks diverge from America/Santiago starting 2017-05-13 at
713 23:00, hiving off a new zone America/Punta_Arenas. Although the
714 Chilean government says this change expires in May 2019, for now
715 assume it's permanent. (Thanks to Juan Correa and Deborah
716 Goldsmith.) This also affects Antarctica/Palmer.
718 Changes to past timestamps
720 Fix many entries for historical timestamps for Europe/Madrid
721 before 1979, to agree with tables compiled by Pere Planesas of the
722 National Astronomical Observatory of Spain. As a side effect,
723 this changes some timestamps for Africa/Ceuta before 1929, which
724 are probably guesswork anyway. (Thanks to Steve Allen and
725 Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
726 correcting the 1901 transition.)
728 Ecuador observed DST from 1992-11-28 to 1993-02-05.
729 (Thanks to Alois Treindl.)
731 Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
732 (Thanks to Stepan Golosunov.)
734 Changes to past and future time zone abbreviations
736 Switch to numeric time zone abbreviations for South America, as
737 part of the ongoing project of removing invented abbreviations.
738 This avoids the need to invent an abbreviation for the new Chilean
739 new zone. Similarly, switch from invented to numeric time zone
740 abbreviations for Afghanistan, American Samoa, the Azores,
741 Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
742 Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
743 Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
744 Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
745 the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
746 Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
747 Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
748 Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
749 Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
750 Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
751 for half-hour daylight saving time in Belize before 1944 and in
752 the Dominican Republic before 1975; and for Canary Islands before
753 1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
754 Indian Summer Time before 1942, for Indonesia before around 1964,
755 for Kenya before 1960, for Liberia before 1973, for Madeira before
756 1967, for Namibia before 1943, for the Netherlands in 1937-9, for
757 Pakistan before 1971, for Western Sahara before 1977, and for
758 Zaporozhye in 1880-1924.
760 For Alaska time from 1900 through 1967, instead of "CAT" use the
761 abbreviation "AST", the abbreviation commonly used at the time
762 (Atlantic Standard Time had not been standardized yet). Use "AWT"
763 and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
765 Use "CST" and "CDT" instead of invented abbreviations for Macau
766 before 1999 and Taiwan before 1938, and use "JST" instead of the
767 invented abbreviation "JCST" for Japan and Korea before 1938.
769 Change to database entry category
771 Move the Pacific/Johnston link from 'australasia' to 'backward',
772 since Johnston is now uninhabited.
776 zic no longer mishandles some transitions in January 2038 when it
777 attempts to work around Qt bug 53071. This fixes a bug affecting
778 Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
779 now contains a workaround, useful when loading a file generated by
780 a buggy zic. (Problem and localtime.c fix reported by Bradley
783 zdump -i now outputs non-hour numeric time zone abbreviations
784 without a colon, e.g., "+0530" rather than "+05:30". This agrees
785 with zic %z and with common practice, and simplifies auditing of
788 zdump is now buildable again with -DUSE_LTZ=0.
789 (Problem reported by Joseph Myers.)
791 zdump.c now always includes private.h, to avoid code duplication
792 with private.h. (Problem reported by Kees Dekker.)
794 localtime.c no longer mishandles early or late timestamps
795 when TZ is set to a POSIX-style string that specifies DST.
796 (Problem reported by Kees Dekker.)
798 date and strftime now cause %z to generate "-0000" instead of
799 "+0000" when the UT offset is zero and the time zone abbreviation
802 Changes to documentation and commentary
804 The 'Theory' file now better documents choice of historical time
805 zone abbreviations. (Problems reported by Michael Deckers.)
807 tz-link.htm now covers leap smearing, which is popular in clouds.
810 Release 2016j - 2016-11-22 23:17:13 -0800
812 Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
814 Changes to future timestamps
816 Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
817 This hives off a new zone Europe/Saratov from Europe/Volgograd.
818 (Thanks to Yuri Konotopov and Stepan Golosunov.)
820 Changes to past timestamps
822 The new zone Asia/Atyrau for Atyraū Region, Kazakhstan, is like
823 Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
824 1999, not fall 1994. (Thanks to Stepan Golosunov.)
826 Changes to past time zone abbreviations
828 Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
829 summer time before 1948. The old use of "EET" was a typo.
833 zic no longer mishandles file systems that lack hard links, fixing
834 bugs introduced in 2016g. (Problems reported by Tom Lane.)
835 Also, when the destination already contains symbolic links, zic
836 should now work better on systems where the 'link' system call
837 does not follow symbolic links.
839 Changes to documentation and commentary
841 tz-link.htm now documents the relationship between release version
842 numbers and development-repository commit tags. (Suggested by
845 The 'Theory' file now documents UT.
847 iso3166.tab now accents "Curaçao", and commentary now mentions
848 the names "Cabo Verde" and "Czechia". (Thanks to Jiří Boháč.)
851 Release 2016i - 2016-11-01 23:19:52 -0700
853 Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
854 reintroduces DST on 2016-11-06.
856 Changes to future timestamps
858 Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
859 2017-01-15 at 03:00. Assume future observances in Tonga will be
860 from the first Sunday in November through the third Sunday in
861 January, like Fiji. (Thanks to Pulu ʻAnau.) Switch to numeric
862 time zone abbreviations for this zone.
864 Changes to past and future timestamps
866 Northern Cyprus is now +03 year round, causing a split in Cyprus
867 time zones starting 2016-10-30 at 04:00. This creates a zone
868 Asia/Famagusta. (Thanks to Even Scharning and Matt Johnson.)
870 Antarctica/Casey switched from +08 to +11 on 2016-10-22.
871 (Thanks to Steffen Thorsen.)
873 Changes to past timestamps
875 Several corrections were made for pre-1975 timestamps in Italy.
876 These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
879 First, the 1893-11-01 00:00 transition in Italy used the new UT
880 offset (+01), not the old (+00:49:56). (Thanks to Michael
883 Second, rules for daylight saving in Italy were changed to agree
884 with Italy's National Institute of Metrological Research (INRiM)
885 except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
886 Inglis, and Michael Deckers):
888 The 1916-06-03 transition was at 24:00, not 00:00.
890 The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
893 The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
896 The 1944-09-17 transition was at 03:00, not 01:00. This
897 particular change is taken from Italian law as INRiM's table,
898 (which says 02:00) appears to have a typo here. Also, keep the
899 1944-04-03 transition for Europe/Rome, as Rome was controlled by
902 The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
907 The code should now be buildable on AmigaOS merely by setting the
908 appropriate Makefile variables. (From a patch by Carsten Larsen.)
911 Release 2016h - 2016-10-19 23:17:57 -0700
913 Changes to future timestamps
915 Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
916 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that
917 future fall transitions will be on the last Saturday of October
918 at 01:00, which is consistent with predicted spring transitions
919 on the last Saturday of March. (Thanks to Tim Parenti.)
921 Changes to past timestamps
923 In Turkey, transitions in 1986-1990 were at 01:00 standard time
924 not at 02:00, and the spring 1994 transition was on March 20, not
925 March 27. (Thanks to Kıvanç Yazan.)
927 Changes to past and future time zone abbreviations
929 Asia/Colombo now uses numeric time zone abbreviations like "+0530"
930 instead of alphabetic ones like "IST" and "LKT". Various
931 English-language sources use "IST", "LKT" and "SLST", with no
932 working consensus. (Usage of "SLST" mentioned by Sadika
937 zic no longer mishandles relativizing file names when creating
938 symbolic links like /etc/localtime, when these symbolic links
939 are outside the usual directory hierarchy. This fixes a bug
940 introduced in 2016g. (Problem reported by Andreas Stieger.)
942 Changes to build procedure
944 New rules 'traditional_tarballs' and 'traditional_signatures' for
945 building just the traditional-format distribution. (Requested by
948 The file 'version' is now put into the tzdata tarball too.
949 (Requested by Howard Hinnant.)
951 Changes to documentation and commentary
953 The 'Theory' file now has a section on interface stability.
954 (Requested by Paul Koning.) It also mentions features like
955 tm_zone and localtime_rz that have long been supported by the
958 tz-link.htm has improved coverage of time zone boundaries suitable
959 for geolocation. (Thanks to heads-ups from Evan Siroky and Matt
962 The US commentary now mentions Allen and the "day of two noons".
964 The Fiji commentary mentions the government's 2016-10-03 press
965 release. (Thanks to Raymond Kumar.)
968 Release 2016g - 2016-09-13 08:56:38 -0700
970 Changes to future timestamps
972 Turkey switched from EET/EEST (+02/+03) to permanent +03,
973 effective 2016-09-07. (Thanks to Burak AYDIN.) Use "+03" rather
974 than an invented abbreviation for the new time.
976 New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
977 (Thanks to Tim Parenti.)
979 Changes to past timestamps
981 For America/Los_Angeles, spring-forward transition times have been
982 corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
985 For zones using Soviet time on 1919-07-01, transitions to UT-based
986 time were at 00:00 UT, not at 02:00 local time. The affected
987 zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
988 Europe/Ulyanovsk. (Thanks to Alexander Belopolsky.)
990 Changes to past and future time zone abbreviations
992 The Factory zone now uses the time zone abbreviation -00 instead
993 of a long English-language string, as -00 is now the normal way to
994 represent an undefined time zone.
996 Several zones in Antarctica and the former Soviet Union, along
997 with zones intended for ships at sea that cannot use POSIX TZ
998 strings, now use numeric time zone abbreviations instead of
999 invented or obsolete alphanumeric abbreviations. The affected
1000 zones are Antarctica/Casey, Antarctica/Davis,
1001 Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
1002 Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
1003 Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
1004 Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
1005 Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
1006 Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
1007 Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
1008 Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
1009 Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
1010 Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
1011 Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
1012 Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
1013 Europe/Minsk, Europe/Samara, Europe/Volgograd, and
1014 Indian/Kerguelen. For Europe/Moscow the invented abbreviation MSM
1015 was replaced by +05, whereas MSK and MSD were kept as they are not
1016 our invention and are widely used.
1018 Changes to zone names
1020 Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
1021 (Thanks to David Massoud.)
1025 zic no longer generates binary files containing POSIX TZ-like
1026 strings that disagree with the local time type after the last
1027 explicit transition in the data. This fixes a bug with
1028 Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
1029 on the reference platform. (Thanks to Alexander Belopolsky for
1030 reporting the bug and suggesting a way forward.)
1032 If the installed localtime and/or posixrules files are symbolic
1033 links, zic now keeps them symbolic links when updating them, for
1034 compatibility with platforms like OpenSUSE where other programs
1035 configure these files as symlinks.
1037 zic now avoids hard linking to symbolic links, avoids some
1038 unnecessary mkdir and stat system calls, and uses shorter file
1041 zdump has a new -i option to generate transitions in a
1042 more-compact but still human-readable format. This option is
1043 experimental, and the output format may change in future versions.
1044 (Thanks to Jon Skeet for suggesting that an option was needed,
1045 and thanks to Tim Parenti and Chris Rovick for further comments.)
1047 Changes to build procedure
1049 An experimental distribution format is available, in addition
1050 to the traditional format which will continue to be distributed.
1051 The new format is a tarball tzdb-VERSION.tar.lz with signature
1052 file tzdb-VERSION.tar.lz.asc. It unpacks to a top-level directory
1053 tzdb-VERSION containing the code and data of the traditional
1054 two-tarball format, along with extra data that may be useful.
1055 (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
1056 for comments about the experimental format.)
1058 The release version number is now more accurate in the usual case
1059 where releases are built from a Git repository. For example, if
1060 23 commits and some working-file changes have been made since
1061 release 2016g, the version number is now something like
1062 '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
1063 Tagged releases use the same version number format as before,
1064 e.g., '2016g'. To support the more-accurate version number, its
1065 specification has moved from a line in the Makefile to a new
1066 source file 'version'.
1068 The experimental distribution contains a file to2050.tzs that
1069 contains what should be the output of 'zdump -i -c 2050' on
1070 primary zones. If this file is available, 'make check' now checks
1071 that zdump generates this output.
1073 'make check_web' now works on Fedora-like distributions.
1075 Changes to documentation and commentary
1077 tzfile.5 now documents the new restriction on POSIX TZ-like
1078 strings that is now implemented by zic.
1080 Comments now cite URLs for some 1917-1921 Russian DST decrees.
1081 (Thanks to Alexander Belopolsky.)
1083 tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
1084 (thanks to Meno Hochschild) and ThreeTen-Extra, and its
1085 description of Java 8 has been brought up to date (thanks to
1086 Stephen Colebourne). Its description of local time on Mars has
1087 been updated to match current practice, and URLs have been updated
1088 and some obsolete ones removed.
1091 Release 2016f - 2016-07-05 16:26:51 +0200
1093 Changes affecting future timestamps
1095 The Egyptian government changed its mind on short notice, and
1096 Africa/Cairo will not introduce DST starting 2016-07-07 after all.
1097 (Thanks to Mina Samuel.)
1099 Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
1100 (Thanks to Stepan Golosunov.)
1102 Changes to past and future timestamps
1104 Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
1105 abbreviations instead of invented ones.
1107 Changes affecting past timestamps
1109 Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
1110 (Thanks to Stepan Golosunov.)
1113 Release 2016e - 2016-06-14 08:46:16 -0700
1115 Changes affecting future timestamps
1117 Africa/Cairo observes DST in 2016 from July 7 to the end of October.
1118 Guess October 27 and 24:00 transitions. (Thanks to Steffen Thorsen.)
1119 For future years, guess April's last Thursday to October's last
1120 Thursday except for Ramadan.
1122 Changes affecting past timestamps
1124 Locations while uninhabited now use '-00', not 'zzz', as a
1125 placeholder time zone abbreviation. This is inspired by Internet
1126 RFC 3339 and is more consistent with numeric time zone
1127 abbreviations already used elsewhere. The change affects several
1128 arctic and antarctic locations, e.g., America/Cambridge_Bay before
1129 1920 and Antarctica/Troll before 2005.
1131 Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
1132 at 03:00, not 23:00 the previous day. (Thanks to Michael Deckers.)
1136 zic now outputs a dummy transition at time 2**31 - 1 in zones
1137 whose POSIX-style TZ strings contain a '<'. This mostly works
1138 around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
1139 (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
1141 Changes affecting documentation and commentary
1143 tz-link.htm says why governments should give plenty of notice for
1144 time zone or DST changes, and refers to Matt Johnson's blog post.
1146 tz-link.htm mentions Tzdata for Elixir. (Thanks to Matt Johnson.)
1149 Release 2016d - 2016-04-17 22:50:29 -0700
1151 Changes affecting future timestamps
1153 America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
1154 (Thanks to Alexander Krivenyshev for the heads-up.)
1156 Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
1157 (Thanks to Alexander Krivenyshev and Matt Johnson.)
1159 New zone Asia/Tomsk, split off from Asia/Novosibirsk. It covers
1160 Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
1161 at 02:00. (Thanks to Stepan Golosunov.)
1163 Changes affecting past timestamps
1165 New zone Europe/Kirov, split off from Europe/Volgograd. It covers
1166 Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
1167 1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
1168 the same change. (Thanks to Stepan Golosunov.)
1170 Russia and nearby locations had daylight-saving transitions on
1171 1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
1172 1992-03-28 at 23:00 and 1992-09-26 at 23:00. (Thanks to Stepan
1175 Many corrections to historical time in Kazakhstan from 1991
1176 through 2005. (Thanks to Stepan Golosunov.) Replace Kazakhstan's
1177 invented time zone abbreviations with numeric abbreviations.
1179 Changes to commentary
1181 Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
1184 Release 2016c - 2016-03-23 00:51:27 -0700
1186 Changes affecting future timestamps
1188 Azerbaijan no longer observes DST. (Thanks to Steffen Thorsen.)
1190 Chile reverts from permanent to seasonal DST. (Thanks to Juan
1191 Correa for the heads-up, and to Tim Parenti for corrections.)
1192 Guess that future transitions are August's and May's second
1193 Saturdays at 24:00 mainland time. Also, call the period from
1194 2014-09-07 through 2016-05-14 daylight saving time instead of
1195 standard time, as that seems more appropriate now.
1197 Changes affecting past timestamps
1199 Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
1200 +02/+03 on 1989-03-26, not 1991-03-31. Europe/Volgograd changed
1201 from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
1202 (Thanks to Stepan Golosunov.)
1204 Changes to commentary
1206 Several updates and URLs for historical and proposed Russian changes.
1207 (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
1210 Release 2016b - 2016-03-12 17:30:14 -0800
1214 Starting with release 2016b, some data entries cause zic implementations
1215 derived from tz releases 2005j through 2015e to issue warnings like
1216 "time zone abbreviation differs from POSIX standard (+03)".
1217 These warnings should not otherwise affect zic's output and can safely be
1218 ignored on today's platforms, as the warnings refer to a restriction in
1219 POSIX.1-1988 that was removed in POSIX.1-2001. One way to suppress the
1220 warnings is to upgrade to zic derived from tz releases 2015f and later.
1222 Changes affecting future timestamps
1224 New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
1225 Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
1226 2016-03-27 at 02:00 local time. They need distinct zones since their
1227 post-1970 histories disagree. New zone Asia/Barnaul for Altai Krai and
1228 Altai Republic, Russia, which will switch from +06 to +07 on the same date
1229 and local time. The Astrakhan change is already official; the others have
1230 passed the first reading in the State Duma and are extremely likely.
1231 Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
1232 (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
1233 and Stepan Golosunov for followup.)
1235 As a trial of a new system that needs less information to be made up,
1236 the new zones use numeric time zone abbreviations like "+04"
1237 instead of invented abbreviations like "ASTT".
1239 Haiti will not observe DST in 2016. (Thanks to Jean Antoine via
1242 Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
1243 (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
1244 Saturday at 01:00, not March's last Friday at 24:00.
1246 Changes affecting past timestamps
1248 Europe/Chisinau observed DST during 1990, and switched from +04 to
1249 +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
1250 (Thanks to Stepan Golosunov.)
1252 1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
1253 KUYT/KUYST. (Thanks to Stepan Golosunov.)
1257 tzselect's diagnostics and checking, and checktab.awk's checking,
1258 have been improved. (Thanks to J William Piggott.)
1260 tzcode now builds under MinGW. (Thanks to Ian Abbott and Esben Haabendal.)
1262 tzselect now tests Julian-date TZ settings more accurately.
1263 (Thanks to J William Piggott.)
1265 Changes to commentary
1267 Comments in zone tables have been improved. (Thanks to J William Piggott.)
1269 tzselect again limits its menu comments so that menus fit on a
1270 24×80 alphanumeric display.
1272 A new web page tz-how-to.html. (Thanks to Bill Seymour.)
1274 In the Theory file, the description of possible time zone abbreviations in
1275 tzdata has been cleaned up, as the old description was unclear and
1276 inconsistent. (Thanks to Alain Mouette for reporting the problem.)
1279 Release 2016a - 2016-01-26 23:28:02 -0800
1281 Changes affecting future timestamps
1283 America/Cayman will not observe daylight saving this year after all.
1284 Revert our guess that it would. (Thanks to Matt Johnson.)
1286 Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
1287 (Thanks to Alexander Krivenyshev.)
1289 Asia/Tehran now has DST predictions for the year 2038 and later,
1290 to be March 21 00:00 to September 21 00:00. This is likely better
1291 than predicting no DST, albeit off by a day every now and then.
1293 Changes affecting past and future timestamps
1295 America/Metlakatla switched from PST all year to AKST/AKDT on
1296 2015-11-01 at 02:00. (Thanks to Steffen Thorsen.)
1298 America/Santa_Isabel has been removed, and replaced with a
1299 backward compatibility link to America/Tijuana. Its contents were
1300 apparently based on a misreading of Mexican legislation.
1302 Changes affecting past timestamps
1304 Asia/Karachi's two transition times in 2002 were off by a minute.
1305 (Thanks to Matt Johnson.)
1307 Changes affecting build procedure
1309 An installer can now combine leap seconds with use of the backzone file,
1310 e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
1311 The old 'make posix_packrat' rule is now marked as obsolescent.
1312 (Thanks to Ian Abbott for an initial implementation.)
1314 Changes affecting documentation and commentary
1316 A new file LICENSE makes it easier to see that the code and data
1317 are mostly public-domain. (Thanks to James Knight.) The three
1318 non-public-domain files now use the current (3-clause) BSD license
1319 instead of older versions of that license.
1321 tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
1322 CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
1323 on editing tz source files (with a mention of Sublime zoneinfo,
1324 thanks to Gilmore Davidson).
1326 The Theory and asia files now mention the 2015 book "The Global
1327 Transformation of Time, 1870-1950", and cite a couple of reviews.
1329 The America/Chicago entry now documents the informal use of US
1330 central time in Fort Pierre, South Dakota. (Thanks to Rick
1331 McDermid, Matt Johnson, and Steve Jones.)
1334 Release 2015g - 2015-10-01 00:39:51 -0700
1336 Changes affecting future timestamps
1338 Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
1341 Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
1342 (Thanks to Alexander Krivenyshev.)
1344 Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
1345 (Thanks to Ken Rylander.)
1347 Fort Nelson, British Columbia will not fall back on 2015-11-01. It has
1348 effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
1349 New zone America/Fort_Nelson. (Thanks to Matt Johnson.)
1351 Changes affecting past timestamps
1353 Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
1355 Changes affecting code
1357 localtime no longer mishandles America/Anchorage after 2037.
1358 (Thanks to Bradley White for reporting the bug.)
1360 On hosts with signed 32-bit time_t, localtime no longer mishandles
1361 Pacific/Fiji after 2038-01-16 14:00 UTC.
1363 The localtime module allows the variables 'timezone', 'daylight',
1364 and 'altzone' to be in common storage shared with other modules,
1365 and declares them in case the system <time.h> does not.
1366 (Problems reported by Kees Dekker.)
1368 On platforms with tm_zone, strftime.c now assumes it is not NULL.
1369 This simplifies the code and is consistent with zdump.c.
1370 (Problem reported by Christos Zoulas.)
1372 Changes affecting documentation
1374 The tzfile man page now documents that transition times denote the
1375 starts (not the ends) of the corresponding time periods.
1376 (Ambiguity reported by Bill Seymour.)
1379 Release 2015f - 2015-08-10 18:06:56 -0700
1381 Changes affecting future timestamps
1383 North Korea switches to +0830 on 2015-08-15. (Thanks to Steffen Thorsen.)
1384 The abbreviation remains "KST". (Thanks to Robert Elz.)
1386 Uruguay no longer observes DST. (Thanks to Steffen Thorsen
1389 Changes affecting past and future timestamps
1391 Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
1392 (Thanks to Roman Tudos.)
1394 Changes affecting data format and code
1396 zic's '-y YEARISTYPE' option is no longer documented. The TYPE
1397 field of a Rule line should now be '-'; the old values 'even',
1398 'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
1399 Although the implementation has not changed, these features do not
1400 work in the default installation, they are not used in the data,
1401 and they are now considered obsolescent.
1403 zic now checks that two rules don't take effect at the same time.
1404 (Thanks to Jon Skeet and Arthur David Olson.) Constraints on
1405 simultaneity are now documented.
1407 The two characters '%z' in a zone format now stand for the UT
1408 offset, e.g., '-07' for seven hours behind UT and '+0530' for
1409 five hours and thirty minutes ahead. This better supports time
1410 zone abbreviations conforming to POSIX.1-2001 and later.
1412 Changes affecting installed data files
1414 Comments for America/Halifax and America/Glace_Bay have been improved.
1415 (Thanks to Brian Inglis.)
1417 Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
1418 Europe/Sofia, and Europe/Tallinn. This yields slightly smaller
1419 installed data files for Europe/Simferopol and Europe/Tallinn.
1420 It does not affect timestamps. (Thanks to Howard Hinnant.)
1422 Changes affecting code
1424 zdump and zic no longer warn about valid time zone abbreviations
1427 Some Visual Studio 2013 warnings have been suppressed.
1428 (Thanks to Kees Dekker.)
1430 'date' no longer sets the time of day and its -a, -d, -n and -t
1431 options have been removed. Long obsolescent, the implementation
1432 of these features had porting problems. Builders no longer need
1433 to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
1434 (Thanks to Kees Dekker for pointing out the problem.)
1436 Changes affecting documentation
1438 The Theory file mentions naming issues earlier, as these seem to be
1439 poorly publicized (thanks to Gilmore Davidson for reporting the problem).
1441 tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
1443 Mention that Herbert Samuel introduced the term "Summer Time".
1446 Release 2015e - 2015-06-13 10:56:02 -0700
1448 Changes affecting future timestamps
1450 Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
1451 not 06-13 and 07-18 as we had guessed. (Thanks to Milamber.)
1453 Assume Cayman Islands will observe DST starting next year, using US rules.
1454 Although it isn't guaranteed, it is the most likely.
1456 Changes affecting data format
1458 The file 'iso3166.tab' now uses UTF-8, so that its entries can better
1459 spell the names of Åland Islands, Côte d'Ivoire, and Réunion.
1461 Changes affecting code
1463 When displaying data, tzselect converts it to the current locale's
1464 encoding if the iconv command works. (Problem reported by random832.)
1466 tzselect no longer mishandles Dominica, fixing a bug introduced
1467 in Release 2014f. (Problem reported by Owen Leibman.)
1469 zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
1470 This fixes a bug introduced in Release 2014f.
1471 (Problem reported by Leonardo Chiquitto.)
1474 Release 2015d - 2015-04-24 08:09:46 -0700
1476 Changes affecting future timestamps
1478 Egypt will not observe DST in 2015 and will consider canceling it
1479 permanently. For now, assume no DST indefinitely.
1480 (Thanks to Ahmed Nazmy and Tim Parenti.)
1482 Changes affecting past timestamps
1484 America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
1485 1966-07-01. Also, Yukon's time zone history is documented better.
1486 (Thanks to Brian Inglis and Dennis Ferguson.)
1488 Change affecting past and future time zone abbreviations
1490 The abbreviations for Hawaii-Aleutian standard and daylight times
1491 have been changed from HAST/HADT to HST/HDT, as per US Government
1492 Printing Office style. This affects only America/Adak since 1983,
1493 as America/Honolulu was already using the new style.
1495 Changes affecting code
1497 zic has some minor performance improvements.
1500 Release 2015c - 2015-04-11 08:55:55 -0700
1502 Changes affecting future timestamps
1504 Egypt's spring-forward transition is at 24:00 on April's last Thursday,
1505 not 00:00 on April's last Friday. 2015's transition will therefore be on
1506 Thursday, April 30 at 24:00, not Friday, April 24 at 00:00. Similar fixes
1507 apply to 2026, 2037, 2043, etc. (Thanks to Steffen Thorsen.)
1509 Changes affecting past timestamps
1511 The following changes affect some pre-1991 Chile-related timestamps
1512 in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
1514 The 1910 transition was January 10, not January 1.
1516 The 1918 transition was September 10, not September 1.
1518 The UT -04 time observed from 1932 to 1942 is now considered to
1519 be standard time, not year-round DST.
1521 Santiago observed DST (UT -03) from 1946-07-15 through
1522 1946-08-31, then reverted to standard time, then switched to -05
1525 Assume transitions before 1968 were at 00:00, since we have no data
1528 The spring 1988 transition was 1988-10-09, not 1988-10-02.
1529 The fall 1990 transition was 1990-03-11, not 1990-03-18.
1531 Assume no UT offset change for Pacific/Easter on 1890-01-01,
1532 and omit all transitions on Pacific/Easter from 1942 through 1946
1533 since we have no data suggesting that they existed.
1535 One more zone has been turned into a link, as it differed
1536 from an existing zone only for older timestamps. As usual,
1537 this change affects UT offsets in pre-1970 timestamps only.
1538 The zone's old contents have been moved to the 'backzone' file.
1539 The affected zone is America/Montreal.
1541 Changes affecting commentary
1543 Mention the TZUpdater tool.
1545 Mention "The Time Now". (Thanks to Brandon Ramsey.)
1548 Release 2015b - 2015-03-19 23:28:11 -0700
1550 Changes affecting future timestamps
1552 Mongolia will start observing DST again this year, from the last
1553 Saturday in March at 02:00 to the last Saturday in September at 00:00.
1554 (Thanks to Ganbold Tsagaankhuu.)
1556 Palestine will start DST on March 28, not March 27. Also,
1557 correct the fall 2014 transition from September 26 to October 24.
1558 Adjust future predictions accordingly. (Thanks to Steffen Thorsen.)
1560 Changes affecting past timestamps
1562 The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
1563 regression. (Thanks to Stuart Bishop for reporting the problem.)
1565 Some more zones have been turned into links, when they differed
1566 from existing zones only for older timestamps. As usual,
1567 these changes affect UT offsets in pre-1970 timestamps only.
1568 Their old contents have been moved to the 'backzone' file.
1569 The affected zones are: America/Antigua, America/Cayman,
1570 Pacific/Midway, and Pacific/Saipan.
1572 Changes affecting time zone abbreviations
1574 Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
1577 Changes affecting code
1579 Fix integer overflow bug in reference 'mktime' implementation.
1580 (Problem reported by Jörg Richter.)
1582 Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
1583 to be used in the same executable as standard-library time_t functions.
1584 (Problems reported by Bradley White.)
1586 Changes affecting commentary
1588 Cite the recent Mexican decree changing Quintana Roo's time zone.
1589 (Thanks to Carlos Raúl Perasso.)
1591 Likewise for the recent Chilean decree. (Thanks to Eduardo Romero Urra.)
1593 Update info about Mars time.
1596 Release 2015a - 2015-01-29 22:35:20 -0800
1598 Changes affecting future timestamps
1600 The Mexican state of Quintana Roo, represented by America/Cancun,
1601 will shift from Central Time with DST to Eastern Time without DST
1602 on 2015-02-01 at 02:00. (Thanks to Steffen Thorsen and Gwillim Law.)
1604 Chile will not change clocks in April or thereafter; its new standard time
1605 will be its old daylight saving time. This affects America/Santiago,
1606 Pacific/Easter, and Antarctica/Palmer. (Thanks to Juan Correa.)
1608 New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
1609 (Thanks to Tim Parenti.)
1611 Changes affecting past timestamps
1613 Iceland observed DST in 1919 and 1921, and its 1939 fallback
1614 transition was Oct. 29, not Nov. 29. Remove incorrect data from
1615 Shanks about time in Iceland between 1837 and 1908.
1617 Some more zones have been turned into links, when they differed
1618 from existing zones only for older timestamps. As usual,
1619 these changes affect UT offsets in pre-1970 timestamps only.
1620 Their old contents have been moved to the 'backzone' file.
1621 The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
1624 Changes affecting code
1626 tzalloc now scrubs time zone abbreviations compatibly with the way
1627 that tzset always has, by replacing invalid bytes with '_' and by
1628 shortening too-long abbreviations.
1630 tzselect ports to POSIX awk implementations, no longer mishandles
1631 POSIX TZ settings when GNU awk is used, and reports POSIX TZ
1632 settings to the user. (Thanks to Stefan Kuhn.)
1634 Changes affecting build procedure
1636 'make check' now checks for links to links in the data.
1637 One such link (for Africa/Asmera) has been fixed.
1638 (Thanks to Stephen Colebourne for pointing out the problem.)
1640 Changes affecting commentary
1642 The leapseconds file commentary now mentions the expiration date.
1643 (Problem reported by Martin Burnicki.)
1645 Update Mexican Library of Congress URL.
1648 Release 2014j - 2014-11-10 17:37:11 -0800
1650 Changes affecting current and future timestamps
1652 Turks & Caicos' switch from US eastern time to UT -04 year-round
1653 did not occur on 2014-11-02 at 02:00. It's currently scheduled
1654 for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
1656 Changes affecting past timestamps
1658 Many pre-1989 timestamps have been corrected for Asia/Seoul and
1659 Asia/Pyongyang, based on sources for the Korean-language Wikipedia
1660 entry for time in Korea. (Thanks to Sanghyuk Jung.) Also, no
1661 longer guess that Pyongyang mimicked Seoul time after World War II,
1662 as this is politically implausible.
1664 Some more zones have been turned into links, when they differed
1665 from existing zones only for older timestamps. As usual,
1666 these changes affect UT offsets in pre-1970 timestamps only.
1667 Their old contents have been moved to the 'backzone' file.
1668 The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
1669 Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
1670 Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
1673 Changes affecting commentary
1675 The commentary is less enthusiastic about Shanks as a source,
1676 and is more careful to distinguish UT from UTC.
1679 Release 2014i - 2014-10-21 22:04:57 -0700
1681 Changes affecting future timestamps
1683 Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
1684 (Thanks to Ken Rylander for the heads-up.) Guess that future
1685 years will use a similar pattern.
1687 A new Zone Pacific/Bougainville, for the part of Papua New Guinea
1688 that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
1689 (Thanks to Kiley Walbom for the heads-up.)
1691 Changes affecting time zone abbreviations
1693 Since Belarus is not changing its clocks even though Moscow is,
1694 the time zone abbreviation in Europe/Minsk is changing from FET
1695 to its more-traditional value MSK on 2014-10-26 at 01:00.
1696 (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
1698 The new abbreviation IDT stands for the pre-1976 use of UT +08 in
1699 Indochina, to distinguish it better from ICT (+07).
1701 Changes affecting past timestamps
1703 Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
1704 (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
1705 authoritative book). Asia/Ho_Chi_Minh has been added to
1706 zone1970.tab, to give tzselect users in Vietnam two choices,
1707 since north and south Vietnam disagreed after our 1970 cutoff.
1709 Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
1710 they differed from existing zones only for older timestamps. As
1711 usual, these changes affect pre-1970 timestamps only. Their old
1712 contents have been moved to the 'backzone' file.
1714 Changes affecting code
1716 The time-related library functions now set errno on failure, and
1717 some crashes in the new tzalloc-related library functions have
1718 been fixed. (Thanks to Christos Zoulas for reporting most of
1719 these problems and for suggesting fixes.)
1721 If USG_COMPAT is defined and the requested timestamp is standard time,
1722 the tz library's localtime and mktime functions now set the extern
1723 variable timezone to a value appropriate for that timestamp; and
1724 similarly for ALTZONE, daylight saving time, and the altzone variable.
1725 This change is a companion to the tzname change in 2014h, and is
1726 designed to make timezone and altzone more compatible with tzname.
1728 The tz library's functions now set errno to EOVERFLOW if they fail
1729 because the result cannot be represented. ctime and ctime_r now
1730 return NULL and set errno when a timestamp is out of range, rather
1731 than having undefined behavior.
1733 Some bugs associated with the new 2014g functions have been fixed.
1734 This includes a bug that largely incapacitated the new functions
1735 time2posix_z and posix2time_z. (Thanks to Christos Zoulas.)
1736 It also includes some uses of uninitialized variables after tzalloc.
1737 The new code uses the standard type 'ssize_t', which the Makefile
1738 now gives porting advice about.
1740 Changes affecting commentary
1742 Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
1745 Release 2014h - 2014-09-25 18:59:03 -0700
1747 Changes affecting past timestamps
1749 America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
1751 Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
1752 not 1920-01-06. The old entry was based on a misinterpretation of Shanks.
1754 Some more zones have been turned into links, when they differed
1755 from existing zones only for older timestamps. As usual,
1756 these changes affect UT offsets in pre-1970 timestamps only.
1757 Their old contents have been moved to the 'backzone' file.
1758 The affected zones are: Africa/Blantyre, Africa/Bujumbura,
1759 Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
1760 Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
1762 Changes affecting code
1764 zdump -V and -v now output gmtoff= values on all platforms,
1765 not merely on platforms defining TM_GMTOFF.
1767 The tz library's localtime and mktime functions now set tzname to a value
1768 appropriate for the requested timestamp, and zdump now uses this
1769 on platforms not defining TM_ZONE, fixing a 2014g regression.
1770 (Thanks to Tim Parenti for reporting the problem.)
1772 The tz library no longer sets tzname if localtime or mktime fails.
1774 zdump -c no longer mishandles transitions near year boundaries.
1775 (Thanks to Tim Parenti for reporting the problem.)
1777 An access to uninitialized data has been fixed.
1778 (Thanks to Jörg Richter for reporting the problem.)
1780 When THREAD_SAFE is defined, the code ports to the C11 memory model.
1781 A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
1782 and two threads race to initialize data used by gmtime-like functions.
1783 (Thanks to Andy Heninger for reporting the problems.)
1785 Changes affecting build procedure
1787 'make check' now checks better for properly-sorted data.
1789 Changes affecting documentation and commentary
1791 zdump's gmtoff=N output is now documented, and its isdst=D output
1792 is now documented to possibly output D values other than 0 or 1.
1794 zdump -c's treatment of years is now documented to use the
1795 Gregorian calendar and Universal Time without leap seconds,
1796 and its behavior at cutoff boundaries is now documented better.
1797 (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
1799 Programs are now documented to use the proleptic Gregorian calendar.
1800 (Thanks to Alan Barrett for the suggestion.)
1802 Fractional-second GMT offsets have been documented for civil time
1803 in 19th-century Chennai, Jakarta, and New York.
1806 Release 2014g - 2014-08-28 12:31:23 -0700
1808 Changes affecting future timestamps
1810 Turks & Caicos is switching from US eastern time to UT -04
1811 year-round, modeled as a switch on 2014-11-02 at 02:00.
1812 [As noted in 2014j, this switch was later delayed.]
1814 Changes affecting past timestamps
1816 Time in Russia or the USSR before 1926 or so has been corrected by
1817 a few seconds in the following zones: Asia/Irkutsk,
1818 Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
1819 Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara. For
1820 Asia/Yekaterinburg the correction is a few minutes. (Thanks to
1821 Vladimir Karpinsky.)
1823 The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
1824 This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
1825 Atlantic/Azores, and Atlantic/Madeira. Also, Lisbon's pre-1912
1826 GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
1827 (Thanks to Stephen Colebourne for pointing to the decree.)
1829 Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
1831 A new file 'backzone' contains data which may appeal to
1832 connoisseurs of old timestamps, although it is out of scope for
1833 the tz database, is often poorly sourced, and contains some data
1834 that is known to be incorrect. The new file is not recommended
1835 for ordinary use and its entries are not installed by default.
1836 (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
1837 Isle of Man entries.)
1839 Some more zones have been turned into links, when they differed
1840 from existing zones only for older timestamps. As usual,
1841 these changes affect UT offsets in pre-1970 timestamps only.
1842 Their old contents have been moved to the 'backzone' file.
1843 The affected zones are: Africa/Bangui, Africa/Brazzaville,
1844 Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
1845 Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
1847 Changes affecting code
1849 Unless NETBSD_INSPIRED is defined to 0, the tz library now
1850 supplies functions for creating and using objects that represent
1851 timezones. The new functions are tzalloc, tzfree, localtime_rz,
1852 mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
1853 time2posix_z. They are intended for performance: for example,
1854 localtime_rz (unlike localtime_r) is trivially thread-safe without
1855 locking. (Thanks to Christos Zoulas for proposing NetBSD-inspired
1856 functions, and to Alan Barrett and Jonathan Lennox for helping to
1859 zdump now builds with the tz library unless USE_LTZ is defined to 0,
1860 This lets zdump use tz features even if the system library lacks them.
1861 To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
1862 TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
1864 zdump now uses localtime_rz if available, as it's significantly faster,
1865 and it can help zdump better diagnose invalid timezone names.
1866 Define HAVE_LOCALTIME_RZ to 0 to suppress this. HAVE_LOCALTIME_RZ
1867 defaults to 1 if NETBSD_INSPIRED && USE_LTZ. When localtime_rz is
1868 not available, zdump now uses localtime_r and tzset if available,
1869 as this is a bit cleaner and faster than plain localtime. Compile
1870 with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
1871 lacks these two functions.
1873 If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
1874 Although not needed for tz's own applications, which are single-threaded,
1875 this supports POSIX better if the tz library is used in multithreaded apps.
1877 Some crashes have been fixed when zdump or the tz library is given
1878 invalid or outlandish input.
1880 The tz library no longer mishandles leap seconds on platforms with
1881 unsigned time_t in timezones that lack ordinary transitions after 1970.
1883 The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
1884 already defined, to make it easier to configure on common platforms.
1885 Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
1887 Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
1888 assumes that reading uninitialized memory yields garbage values
1889 but does not cause other problems such as traps.
1891 If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
1892 more likely to guess right for ambiguous timestamps near
1893 transitions where tm_isdst does not change.
1895 If HAVE_STRFTIME_L is defined to 1, the tz library now defines
1896 strftime_l for compatibility with recent versions of POSIX.
1897 Only the C locale is supported, though. HAVE_STRFTIME_L defaults
1898 to 1 on recent POSIX versions, and to 0 otherwise.
1900 tzselect -c now uses a hybrid distance measure that works better
1901 in Africa. (Thanks to Alan Barrett for noting the problem.)
1903 The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
1904 or when time_tz is defined.
1906 When HAVE_UTMPX_H is set the 'date' command now builds on systems
1907 whose <utmpx.h> file does not define WTMPX_FILE, and when setting
1908 the date it updates the wtmpx file if _PATH_WTMPX is defined.
1909 This affects GNU/Linux and similar systems.
1911 For easier maintenance later, some C code has been simplified,
1912 some lint has been removed, and the code has been tweaked so that
1913 plain 'make' is more likely to work.
1915 The C type 'bool' is now used for boolean values, instead of 'int'.
1917 The long-obsolete LOCALE_HOME code has been removed.
1919 The long-obsolete 'gtime' function has been removed.
1921 Changes affecting build procedure
1923 'zdump' no longer links in ialloc.o, as it's not needed.
1925 'make check_time_t_alternatives' no longer assumes GNU diff.
1927 Changes affecting distribution tarballs
1929 The files checktab.awk and zoneinfo2tdf.pl are now distributed in
1930 the tzdata tarball instead of the tzcode tarball, since they help
1931 maintain the data. The NEWS and Theory files are now also
1932 distributed in the tzdata tarball, as they're relevant for data.
1933 (Thanks to Alan Barrett for pointing this out.) Also, the
1934 leapseconds.awk file is no longer distributed in the tzcode
1935 tarball, since it belongs in the tzdata tarball (where 2014f
1936 inadvertently also distributed it).
1938 Changes affecting documentation and commentary
1940 A new file CONTRIBUTING is distributed. (Thanks to Tim Parenti for
1941 suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
1944 The man pages have been updated to use function prototypes,
1945 to document thread-safe variants like localtime_r, and to document
1946 the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
1949 The fields in Link lines have been renamed to be more descriptive
1950 and more like the parameters of 'ln'. LINK-FROM has become TARGET,
1951 and LINK-TO has become LINK-NAME.
1953 tz-link.htm mentions the IETF's tzdist working group; Windows
1954 Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
1956 Some broken URLs have been fixed in the commentary. (Thanks to
1959 Commentary about Philippines DST has been updated, and commentary
1960 on pre-1970 time in India has been added.
1963 Release 2014f - 2014-08-05 17:42:36 -0700
1965 Changes affecting future timestamps
1967 Russia will subtract an hour from most of its time zones on 2014-10-26
1968 at 02:00 local time. (Thanks to Alexander Krivenyshev.)
1969 There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
1970 Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
1971 (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
1972 (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
1973 (Europe/Samara) are not changing their clocks. The changed zones are
1974 Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
1975 Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
1976 Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
1977 Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
1978 subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
1979 but not its UTC offset. Two zones are added: Asia/Chita (split
1980 from Asia/Yakutsk, and also with two hours subtracted) and
1981 Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
1982 subtracted). (Thanks to Tim Parenti for much of the above.)
1984 Changes affecting time zone abbreviations
1986 Australian eastern time zone abbreviations are now AEST/AEDT not EST,
1987 and similarly for the other Australian zones. That is, for eastern
1988 standard and daylight saving time the abbreviations are AEST and AEDT
1989 instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
1990 and AWST/AWDT are now used instead of the former CST, CWST, and WST.
1991 This change does not affect UT offsets, only time zone abbreviations.
1992 (Thanks to Rich Tibbett and many others.)
1994 Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
1995 effective 2014-10-26 at 02:00 local time.
1997 The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
1998 has been changed from URUT to XJT. (Thanks to Luther Ma.)
2000 Prefer MSK/MSD for Moscow time in Russia, even in other cities.
2001 Similarly, prefer EET/EEST for eastern European time in Russia.
2003 Change time zone abbreviations in (western) Samoa to use "ST" and
2004 "DT" suffixes, as this is more likely to match common practice.
2005 Prefix "W" to (western) Samoa time when its standard-time offset
2006 disagrees with that of American Samoa.
2008 America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
2010 Time zone abbreviations have been updated for Japan's two time
2011 zones used 1896-1937. JWST now stands for Western Standard
2012 Time, and JCST for Central Standard Time (formerly this was CJT).
2013 These abbreviations are now used for time in Korea, Taiwan,
2014 and Sakhalin while controlled by Japan.
2016 Changes affecting past timestamps
2018 China's five zones have been simplified to two, since the post-1970
2019 differences in the other three seem to have been imaginary. The
2020 zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
2021 removed; backwards-compatibility links still work, albeit with
2022 different behaviors for timestamps before May 1980. Asia/Urumqi's
2023 1980 transition to UT +08 has been removed, so that it is now at
2024 +06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
2025 Treindl sent helpful translations of two papers by Guo Qingsheng.)
2027 Some zones have been turned into links, when they differed from existing
2028 zones only for older UT offsets where data entries were likely invented.
2029 These changes affect UT offsets in pre-1970 timestamps only. This is
2030 similar to the change in release 2013e, except this time for western
2031 Africa. The affected zones are: Africa/Bamako, Africa/Banjul,
2032 Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
2033 Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
2034 Atlantic/St_Helena. This also affects the backwards-compatibility
2035 link Africa/Timbuktu. (Thanks to Alan Barrett, Stephen Colebourne,
2036 Tim Parenti, and David Patte for reporting problems in earlier
2037 versions of this change.)
2039 Asia/Shanghai's pre-standard-time UT offset has been changed from
2040 8:05:57 to 8:05:43, the location of Xujiahui Observatory. Its
2041 transition to standard time has been changed from 1928 to 1901.
2043 Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
2044 then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
2045 In 1946 it observed DST from 05-15 through 09-30; in 1947
2046 from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
2047 (Thanks to Yu-Cheng Chuang.)
2049 Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
2051 Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
2052 10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
2054 Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
2055 period from 1911 to 1950.
2057 Pacific/Chatham has been changed to New Zealand standard time plus
2058 45 minutes for the period before 1957, reflecting a 1956 remark in
2059 the New Zealand parliament.
2061 Europe/Budapest has several pre-1946 corrections: in 1918 the transition
2062 out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
2063 1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
2064 not 04-06 at 02:00; and there was no DST in 1920.
2066 Africa/Accra is now assumed to have observed DST from 1920 through 1935.
2068 Time in Russia before 1927 or so has been corrected by a few seconds in
2069 the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
2070 Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
2071 Europe/Riga. Also, Moscow's location has been changed to its Kilometer 0
2072 point. (Thanks to Vladimir Karpinsky for the Moscow changes.)
2074 Changes affecting data format
2076 A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
2077 The new file's extended format allows multiple country codes per zone.
2078 The older file is still installed but is deprecated; its format is
2079 not changing and it will still be distributed for a while, but new
2080 applications should use the new file.
2082 The new file format simplifies maintenance of obscure locations.
2083 To test this, it adds coverage for the Crozet Islands and the
2084 Scattered Islands. (Thanks to Tobias Conradi and Antoine Leca.)
2086 The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
2087 It is still ASCII now, but commentary about the switch has been added.
2088 The new file 'zone1970.tab' already uses UTF-8.
2090 Changes affecting code
2092 'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
2093 is defined. (Thanks to Elliott Hughes for reporting the problem.)
2095 'zic' no longer mishandles input when ignoring case in locales that
2096 are not compatible with English, e.g., unibyte Turkish locales when
2097 compiled with HAVE_GETTEXT.
2099 Error diagnostics of 'zic' and 'yearistype' have been reworded so that
2100 they no longer use ASCII '-' as if it were a dash.
2102 'zic' now rejects output file names that contain '.' or '..' components.
2103 (Thanks to Tim Parenti for reporting the problem.)
2105 'zic -v' now warns about output file names that do not follow
2106 POSIX rules, or that contain a digit or '.'. (Thanks to Arthur
2107 David Olson for starting the ball rolling on this.)
2109 Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
2111 Changes affecting build procedure
2113 'zic' no longer links in localtime.o and asctime.o, as they're not needed.
2114 (Thanks to John Cochran.)
2116 Changes affecting documentation and commentary
2118 The 'Theory' file documents legacy names, the longstanding
2119 exceptions to the POSIX-inspired file name rules.
2121 The 'zic' documentation clarifies the role of time types when
2122 interpreting dates. (Thanks to Arthur David Olson.)
2124 Documentation and commentary now prefer UTF-8 to US-ASCII,
2125 allowing the use of proper accents in foreign words and names.
2126 Code and data have not changed because of this. (Thanks to
2127 Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
2130 Non-HTML documentation and commentary now use plain-text URLs instead of
2131 HTML insertions, and are more consistent about bracketing URLs when they
2132 are not already surrounded by white space. (Thanks to suggestions by
2135 There is new commentary about Xujiahui Observatory, the five time-zone
2136 project in China from 1918 to 1949, timekeeping in Japanese-occupied
2137 Shanghai, and Tibet Time in the 1950s. The sharp-eyed can spot the
2138 warlord Jin Shuren in the data.
2140 Commentary about the coverage of each Russian zone has been standardized.
2141 (Thanks to Tim Parenti).
2143 There is new commentary about contemporary timekeeping in Ethiopia.
2145 Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
2147 There is new commentary about time in Poland in 1919.
2149 Proper credit has been given to DST inventor George Vernon Hudson.
2151 Commentary about time in Metlakatla, AK and Resolute, NU has been
2152 improved, with a new source for the former.
2154 In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
2157 Commentary about permanent Antarctic bases has been updated.
2159 Several typos have been corrected. (Thanks to Tim Parenti for
2160 contributing some of these fixes.)
2162 tz-link.htm now mentions the JavaScript libraries Moment Timezone,
2163 TimezoneJS.Date, Walltime-js, and Timezone. (Thanks to a heads-up
2164 from Matt Johnson.) Also, it mentions the Go 'latlong' package.
2165 (Thanks to a heads-up from Dirkjan Ochtman.)
2167 The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
2168 have been removed. These obsolescent US Naval Observatory entries were no
2169 longer helpful for maintenance. (Thanks to Tim Parenti for the suggestion.)
2172 Release 2014e - 2014-06-12 21:53:52 -0700
2174 Changes affecting near-future timestamps
2176 Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
2177 (Thanks to Imed Chihi.) Guess that from 2015 on Egypt will temporarily
2178 switch to standard time at 24:00 the last Thursday before Ramadan, and
2179 back to DST at 00:00 the first Friday after Ramadan.
2181 Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00. (Thanks
2182 to Milamber Space Network.) Guess that from 2015 on Morocco will
2183 temporarily switch to standard time at 03:00 the last Saturday before
2184 Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
2186 Changes affecting past timestamps
2188 The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
2189 "MSD" for Moscow's double daylight time in summer 1921. Also, a typo
2190 "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
2191 in 1991. (Thanks to Hank W. for reporting the problems.)
2193 Changes affecting commentary
2195 tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
2196 draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
2197 removes stale pointers to World Time Explorer and WORLDTIME.
2200 Release 2014d - 2014-05-27 21:34:40 -0700
2202 Changes affecting code
2204 zic no longer generates files containing timestamps before the Big Bang.
2205 This works around GNOME glib bug 878
2206 <https://gitlab.gnome.org/GNOME/glib/issues/878>
2207 (Thanks to Leonardo Chiquitto for reporting the bug, and to
2208 Arthur David Olson and James Cloos for suggesting improvements to the fix.)
2210 Changes affecting documentation
2212 tz-link.htm now mentions GNOME.
2215 Release 2014c - 2014-05-13 07:44:13 -0700
2217 Changes affecting near-future timestamps
2219 Egypt observes DST starting 2014-05-15 at 24:00.
2220 (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
2221 Details have not been announced, except that DST will not be observed
2222 during Ramadan. Guess that DST will stop during the same Ramadan dates as
2223 Morocco, and that Egypt's future spring and fall transitions will be the
2224 same as 2010 when it last observed DST, namely April's last Friday at
2225 00:00 to September's last Thursday at 23:00 standard time. Also, guess
2226 that Ramadan transitions will be at 00:00 standard time.
2228 Changes affecting code
2230 zic now generates transitions for minimum time values, eliminating guesswork
2231 when handling low-valued timestamps. (Thanks to Arthur David Olson.)
2233 Port to Cygwin sans glibc. (Thanks to Arthur David Olson.)
2235 Changes affecting commentary and documentation
2237 Remove now-confusing comment about Jordan. (Thanks to Oleksii Nochovnyi.)
2240 Release 2014b - 2014-03-24 21:28:50 -0700
2242 Changes affecting near-future timestamps
2244 Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
2245 (Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
2247 New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and
2248 Bengt-Inge Larsson.) This is currently an approximation; a better version
2249 will require the zic and localtime fixes mentioned below, and the plan is
2250 to wait for a while until at least the zic fixes propagate.
2252 Changes affecting code
2254 'zic' and 'localtime' no longer reject locations needing four transitions
2255 per year for the foreseeable future. (Thanks to Andrew Main (Zefram).)
2256 Also, 'zic' avoids some unlikely failures due to integer overflow.
2258 Changes affecting build procedure
2260 'make check' now detects Rule lines defined but never used.
2261 The NZAQ rules, an instance of this problem, have been removed.
2263 Changes affecting commentary and documentation
2265 Fix Tuesday/Thursday typo in description of time in Israel.
2266 (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
2268 Microsoft Windows 8.1 doesn't support tz database names. (Thanks
2269 to Donald MacQueen.) Instead, the Microsoft Windows Store app
2270 library supports them.
2272 Add comments about Johnston Island time in the 1960s.
2273 (Thanks to Lyle McElhaney.)
2275 Morocco's 2014 DST start will be as predicted.
2276 (Thanks to Sebastien Willemijns.)
2279 Release 2014a - 2014-03-07 23:30:29 -0800
2281 Changes affecting near-future timestamps
2283 Turkey begins DST on 2014-03-31, not 03-30. (Thanks to Faruk Pasin for
2284 the heads-up, and to Tim Parenti for simplifying the update.)
2286 Changes affecting past timestamps
2288 Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
2289 (Thanks to Steffen Thorsen.)
2291 Ukraine switched from Moscow to Eastern European time on 1990-07-01
2292 (not 1992-01-01), and observed DST during the entire next winter.
2293 (Thanks to Vladimir in Moscow via Alois Treindl.)
2295 In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
2296 (Thanks to Avigdor Finkelstein.)
2298 Changes affecting code
2300 A uninitialized-storage bug in 'localtime' has been fixed.
2301 (Thanks to Logan Chien.)
2303 Changes affecting the build procedure
2305 The settings for 'make check_web' now default to Ubuntu 13.10.
2307 Changes affecting commentary and documentation
2309 The boundary of the US Pacific time zone is given more accurately.
2310 (Thanks to Alan Mintz.)
2312 Chile's 2014 DST will be as predicted. (Thanks to José Miguel Garrido.)
2314 Paraguay's 2014 DST will be as predicted. (Thanks to Carlos Raúl Perasso.)
2316 Better descriptions of countries with same time zone history as
2317 Trinidad and Tobago since 1970. (Thanks to Alan Barrett for suggestion.)
2319 Several changes affect tz-link.htm, the main web page.
2321 Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
2324 Mention xCal (Internet RFC 6321) and jCal.
2326 Microsoft has some support for tz database names.
2328 CLDR data formats include both XML and JSON.
2330 Mention Maggiolo's map of solar vs standard time.
2331 (Thanks to Arthur David Olson.)
2333 Mention TZ4Net. (Thanks to Matt Johnson.)
2335 Mention the timezone-olson Haskell package.
2337 Mention zeitverschiebung.net. (Thanks to Martin Jäger.)
2339 Remove moribund links to daylight-savings-time.info and to
2340 Simple Timer + Clocks.
2342 Update two links. (Thanks to Oscar van Vlijmen.)
2344 Fix some formatting glitches, e.g., remove random newlines from
2345 abbr elements' title attributes.
2348 Release 2013i - 2013-12-17 07:25:23 -0800
2350 Changes affecting near-future timestamps:
2352 Jordan switches back to standard time at 00:00 on December 20, 2013.
2353 The 2006-2011 transition schedule is planned to resume in 2014.
2354 (Thanks to Steffen Thorsen.)
2356 Changes affecting past timestamps:
2358 In 2004, Cuba began DST on March 28, not April 4.
2359 (Thanks to Steffen Thorsen.)
2361 Changes affecting code
2363 The compile-time flag NOSOLAR has been removed, as nowadays the
2364 benefit of slightly shrinking runtime table size is outweighed by the
2365 cost of disallowing potential future updates that exceed old limits.
2367 Changes affecting documentation and commentary
2369 The files solar87, solar88, and solar89 are no longer distributed.
2370 They were a negative experiment - that is, a demonstration that
2371 tz data can represent solar time only with some difficulty and error.
2372 Their presence in the distribution caused confusion, as Riyadh
2373 civil time was generally not solar time in those years.
2375 tz-link.htm now mentions Noda Time. (Thanks to Matt Johnson.)
2378 Release 2013h - 2013-10-25 15:32:32 -0700
2380 Changes affecting current and future timestamps:
2382 Libya has switched its UT offset back to +02 without DST, instead
2383 of +01 with DST. (Thanks to Even Scharning.)
2385 Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
2386 (Thanks to Gwillim Law.)
2388 Changes affecting future timestamps:
2390 Acre and (we guess) western Amazonas will switch from UT -04 to -05
2391 on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
2392 (Thanks to Steffen Thorsen.)
2394 Add entries for DST transitions in Morocco in the year 2038.
2395 This avoids some year-2038 glitches introduced in 2013g.
2396 (Thanks to Yoshito Umaoka for reporting the problem.)
2398 Changes affecting API
2400 The 'tzselect' command no longer requires the 'select' command,
2401 and should now work with /bin/sh on more platforms. It also works
2402 around a bug in BusyBox awk before version 1.21.0. (Thanks to
2403 Patrick 'P. J.' McDermott and Alan Barrett.)
2405 Changes affecting code
2407 Fix localtime overflow bugs with 32-bit unsigned time_t.
2409 zdump no longer assumes sscanf returns maximal values on overflow.
2411 Changes affecting the build procedure
2413 The builder can specify which programs to use, if any, instead of
2414 'ar' and 'ranlib', and libtz.a is now built locally before being
2415 installed. (Thanks to Michael Forney.)
2417 A dependency typo in the 'zdump' rule has been fixed.
2418 (Thanks to Andrew Paprocki.)
2420 The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
2421 work as specified by POSIX.2-1992 or later; this is portable nowadays.
2423 'make clean' no longer removes 'leapseconds', since it's
2424 host-independent and is part of the distribution.
2426 The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
2428 Changes affecting documentation and commentary
2430 tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
2431 (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
2433 Update URLs in tz-link page. Add URLs for Microsoft Windows, since
2434 8.1 introduces tz support. Remove URLs for Tru64 and UnixWare (no
2435 longer maintained) and for old advisories. SOFA now does C.
2437 Release 2013g - 2013-09-30 21:08:26 -0700
2439 Changes affecting current and near-future timestamps
2441 Morocco now observes DST from the last Sunday in March to the last
2442 Sunday in October, not April to September respectively. (Thanks
2443 to Steffen Thorsen.)
2445 Changes affecting 'zic'
2447 'zic' now runs on platforms that lack both hard links and symlinks.
2448 (Thanks to Theo Veenker for reporting the problem, for MinGW.)
2449 Also, fix some bugs on platforms that lack hard links but have symlinks.
2451 'zic -v' again warns that Asia/Tehran has no POSIX environment variable
2452 to predict the far future, fixing a bug introduced in 2013e.
2454 Changes affecting the build procedure
2456 The 'leapseconds' file is again put into the tzdata tarball.
2457 Also, 'leapseconds.awk', so tzdata is self-contained. (Thanks to
2458 Matt Burgess and Ian Abbott.) The timestamps of these and other
2459 dependent files in tarballs are adjusted more consistently.
2461 Changes affecting documentation and commentary
2463 The README file is now part of the data tarball as well as the code.
2464 It now states that files are public domain unless otherwise specified.
2465 (Thanks to Andrew Main (Zefram) for asking for clarifications.)
2466 Its details about the 1989 release moved to a place of honor near
2470 Release 2013f - 2013-09-24 23:37:36 -0700
2472 Changes affecting near-future timestamps
2474 Tocantins will very likely not observe DST starting this spring.
2475 (Thanks to Steffen Thorsen.)
2477 Jordan will likely stay at UT +03 indefinitely, and will not fall
2480 Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
2482 Changes affecting API
2484 The types of the global variables 'timezone' and 'altzone' (if present)
2485 have been changed back to 'long'. This is required for 'timezone'
2486 by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
2487 These variables were originally 'long' in the tz code, but were
2488 mistakenly changed to 'time_t' in 1987; nobody reported the
2489 incompatibility until now. The difference matters on x32, where
2490 'long' is 32 bits and 'time_t' is 64. (Thanks to Elliott Hughes.)
2492 Changes affecting the build procedure
2494 Avoid long strings in leapseconds.awk to work around a mawk bug.
2495 (Thanks to Cyril Baurand.)
2497 Changes affecting documentation and commentary
2499 New file 'NEWS' that contains release notes like this one.
2501 Paraguay's law does not specify DST transition time; 00:00 is customary.
2502 (Thanks to Waldemar Villamayor-Venialbo.)
2504 Minor capitalization fixes.
2506 Changes affecting version-control only
2508 The experimental GitHub repository now contains annotated and
2509 signed tags for recent releases, e.g., '2013e' for Release 2013e.
2510 Releases are tagged starting with 2012e; earlier releases were
2511 done differently, and tags would either not have a simple name or
2512 not exactly match what was released.
2514 'make set-timestamps' is now simpler and a bit more portable.
2517 Release 2013e - 2013-09-19 23:50:04 -0700
2519 Changes affecting near-future timestamps
2521 This year Fiji will start DST on October 27, not October 20.
2522 (Thanks to David Wheeler for the heads-up.) For now, guess that
2523 Fiji will continue to spring forward the Sunday before the fourth
2526 Changes affecting current and future time zone abbreviations
2528 Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
2529 time zone abbreviations since 1932. (Thanks to George Ziegler,
2530 Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
2531 Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
2532 Asia/Makassar, and Asia/Pontianak.
2534 Use ART (UT -03, standard time), rather than WARST (also -03, but
2535 daylight saving time) for San Luis, Argentina since 2009.
2537 Changes affecting Godthåb timestamps after 2037 if version mismatch
2539 Allow POSIX-like TZ strings where the transition time's hour can
2540 range from -167 through 167, instead of the POSIX-required 0
2541 through 24. E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
2542 new Fiji rules. This is a more-compact way to represent
2543 far-future timestamps for America/Godthab, America/Santiago,
2544 Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
2545 Pacific/Easter, and Pacific/Fiji. Other zones are unaffected by
2546 this change. (Derived from a suggestion by Arthur David Olson.)
2548 Allow POSIX-like TZ strings where daylight saving time is in
2549 effect all year. E.g., TZ='WART4WARST,J1/0,J365/25' for Western
2550 Argentina Summer Time all year. This supports a more-compact way
2551 to represent the 2013d data for America/Argentina/San_Luis.
2552 Because of the change for San Luis noted above this change does not
2553 affect the current data. (Thanks to Andrew Main (Zefram) for
2554 suggestions that improved this change.)
2556 Where these two TZ changes take effect, there is a minor extension
2557 to the tz file format in that it allows new values for the
2558 embedded TZ-format string, and the tz file format version number
2559 has therefore been increased from 2 to 3 as a precaution.
2560 Version-2-based client code should continue to work as before for
2561 all timestamps before 2038. Existing version-2-based client code
2562 (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
2563 files, and typically works in practice even for timestamps after
2564 2037; the only known exception is America/Godthab.
2566 Changes affecting timestamps before 1970
2568 Pacific/Johnston is now a link to Pacific/Honolulu. This corrects
2569 some errors before 1947.
2571 Some zones have been turned into links, when they differ from existing
2572 zones only in older data entries that were likely invented or that
2573 differ only in LMT or transitions from LMT. These changes affect
2574 only timestamps before 1943. The affected zones are:
2575 Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
2576 America/Grenada, America/Guadeloupe, America/Marigot,
2577 America/Montserrat, America/St_Barthelemy, America/St_Kitts,
2578 America/St_Lucia, America/St_Thomas, America/St_Vincent,
2579 America/Tortola, and Europe/Vaduz. (Thanks to Alois Treindl for
2580 confirming that the old Europe/Vaduz zone was wrong and the new
2581 link is better for WWII-era times.)
2583 Change Kingston Mean Time from -5:07:12 to -5:07:11. This affects
2584 America/Cayman, America/Jamaica and America/Grand_Turk timestamps
2587 Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
2588 This affects Europe/Zurich timestamps from 1853 to 1894. (Thanks
2591 Change the date of the circa-1850 Zurich transition from 1849-09-12
2592 to 1853-07-16, overriding Shanks with data from Messerli about
2593 postal and telegraph time in Switzerland.
2595 Changes affecting time zone abbreviations before 1970
2597 For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
2598 as Jakarta was called Batavia back then.
2600 Changes affecting API
2602 The 'zic' command now outputs a dummy transition when far-future
2603 data can't be summarized using a TZ string, and uses a 402-year
2604 window rather than a 400-year window. For the current data, this
2605 affects only the Asia/Tehran file. It does not affect any of the
2606 timestamps that this file represents, so zdump outputs the same
2607 information as before. (Thanks to Andrew Main (Zefram).)
2609 The 'date' command has a new '-r' option, which lets you specify
2610 the integer time to display, a la FreeBSD.
2612 The 'tzselect' command has two new options '-c' and '-n', which lets you
2613 select a zone based on latitude and longitude.
2615 The 'zic' command's '-v' option now warns about constructs that
2616 require the new version-3 binary file format. (Thanks to Arthur
2617 David Olson for the suggestion.)
2619 Support for floating-point time_t has been removed.
2620 It was always dicey, and POSIX no longer requires it.
2621 (Thanks to Eric Blake for suggesting to the POSIX committee to
2622 remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
2623 Heninger, Arthur David Olson, and Alois Treindl, for reporting
2624 bugs and elucidating some of the corners of the old floating-point
2627 The signatures of 'offtime', 'timeoff', and 'gtime' have been
2628 changed back to the old practice of using 'long' to represent UT
2629 offsets. This had been inadvertently and mistakenly changed to
2630 'int_fast32_t'. (Thanks to Christos Zoulas.)
2632 The code avoids undefined behavior on integer overflow in some
2633 more places, including gmtime, localtime, mktime and zdump.
2635 Changes affecting the zdump utility
2637 zdump now outputs "UT" when referring to Universal Time, not "UTC".
2638 "UTC" does not make sense for timestamps that predate the introduction
2639 of UTC, whereas "UT", a more-generic term, does. (Thanks to Steve Allen
2640 for clarifying UT vs UTC.)
2642 Data changes affecting behavior of tzselect and similar programs
2644 Country code BQ is now called the more-common name "Caribbean Netherlands"
2645 rather than the more-official "Bonaire, St Eustatius & Saba".
2647 Remove from zone.tab the names America/Montreal, America/Shiprock,
2648 and Antarctica/South_Pole, as they are equivalent to existing
2649 same-country-code zones for post-1970 timestamps. The data entries for
2650 these names are unchanged, so the names continue to work as before.
2652 Changes affecting code internals
2654 zic -c now runs way faster on 64-bit hosts when given large numbers.
2656 zic now uses vfprintf to avoid allocating and freeing some memory.
2658 tzselect now computes the list of continents from the data,
2659 rather than have it hard-coded.
2661 Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
2663 Changes affecting the build procedure
2665 The 'leapseconds' file is now generated automatically from a
2666 new file 'leap-seconds.list', which is a copy of
2667 <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
2668 A new source file 'leapseconds.awk' implements this.
2669 The goal is simplification of the future maintenance of 'leapseconds'.
2671 When building the 'posix' or 'right' subdirectories, if the
2672 subdirectory would be a copy of the default subdirectory, it is
2673 now made a symbolic link if that is supported. This saves about
2674 2 MB of file system space.
2676 The links America/Shiprock and Antarctica/South_Pole have been
2677 moved to the 'backward' file. This affects only nondefault builds
2678 that omit 'backward'.
2680 Changes affecting version-control only
2682 .gitignore now ignores 'date'.
2684 Changes affecting documentation and commentary
2686 Changes to the 'tzfile' man page
2688 It now mentions that the binary file format may be extended in
2689 future versions by appending data.
2691 It now refers to the 'zdump' and 'zic' man pages.
2693 Changes to the 'zic' man page
2695 It lists conditions that elicit a warning with '-v'.
2697 It says that the behavior is unspecified when duplicate names
2698 are given, or if the source of one link is the target of another.
2700 Its examples are updated to match the latest data.
2702 The definition of white space has been clarified slightly.
2703 (Thanks to Michael Deckers.)
2705 Changes to the 'Theory' file
2707 There is a new section about the accuracy of the tz database,
2708 describing the many ways that errors can creep in, and
2709 explaining why so many of the pre-1970 timestamps are wrong or
2710 misleading (thanks to Steve Allen, Lester Caine, and Garrett
2711 Wollman for discussions that contributed to this).
2713 The 'Theory' file describes LMT better (this follows a
2714 suggestion by Guy Harris).
2716 It refers to the 2013 edition of POSIX rather than the 2004 edition.
2718 It's mentioned that excluding 'backward' should not affect the
2719 other data, and it suggests at least one zone.tab name per
2720 inhabited country (thanks to Stephen Colebourne).
2722 Some longstanding restrictions on names are documented, e.g.,
2723 'America/New_York' precludes 'America/New_York/Bronx'.
2725 It gives more reasons for the 1970 cutoff.
2727 It now mentions which time_t variants are supported, such as
2728 signed integer time_t. (Thanks to Paul Goyette for reporting
2729 typos in an experimental version of this change.)
2731 (Thanks to Philip Newton for correcting typos in these changes.)
2733 Documentation and commentary is more careful to distinguish UT in
2734 general from UTC in particular. (Thanks to Steve Allen.)
2736 Add a better source for the Zurich 1894 transition.
2737 (Thanks to Pierre-Yves Berger.)
2739 Update shapefile citations in tz-link.htm. (Thanks to Guy Harris.)
2742 Release 2013d - 2013-07-05 07:38:01 -0700
2744 Changes affecting future timestamps:
2746 Morocco's midsummer transitions this year are July 7 and August 10,
2747 not July 9 and August 8. (Thanks to Andrew Paprocki.)
2749 Israel now falls back on the last Sunday of October.
2750 (Thanks to Ephraim Silverberg.)
2752 Changes affecting past timestamps:
2754 Specify Jerusalem's location more precisely; this changes the pre-1880
2757 Changing affecting metadata only:
2759 Fix typos in the entries for country codes BQ and SX.
2761 Changes affecting code:
2763 Rework the code to fix a bug with handling Australia/Macquarie on
2764 32-bit hosts (thanks to Arthur David Olson).
2766 Port to platforms like NetBSD, where time_t can be wider than long.
2768 Add support for testing time_t types other than the system's.
2769 Run 'make check_time_t_alternatives' to try this out.
2770 Currently, the tests fail for unsigned time_t;
2771 this should get fixed at some point.
2773 Changes affecting documentation and commentary:
2775 Deemphasize the significance of national borders.
2777 Update the zdump man page.
2779 Remove obsolete NOID comment (thanks to Denis Excoffier).
2781 Update several URLs and comments in the web pages.
2783 Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
2785 Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
2788 Release 2013c - 2013-04-19 16:17:40 -0700
2790 Changes affecting current and future timestamps:
2792 Palestine observed DST starting March 29, 2013. (Thanks to
2793 Steffen Thorsen.) From 2013 on, Gaza and Hebron both observe DST,
2794 with the predicted rules being the last Thursday in March at 24:00
2795 to the first Friday on or after September 21 at 01:00.
2797 Assume that the recent change to Paraguay's DST rules is permanent,
2798 by moving the end of DST to the 4th Sunday in March every year.
2799 (Thanks to Carlos Raúl Perasso.)
2801 Changes affecting past timestamps:
2803 Fix some historical data for Palestine to agree with that of
2804 timeanddate.com, as follows:
2806 The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
2809 The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
2812 The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
2814 The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
2816 The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
2818 The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
2820 Fix times of habitation for Macquarie to agree with the Tasmania
2821 Parks & Wildlife Service history, which indicates that permanent
2822 habitation was 1899-1919 and 1948 on.
2824 Changing affecting metadata only:
2826 Macquarie Island is politically part of Australia, not Antarctica.
2827 (Thanks to Tobias Conradi.)
2829 Sort Macquarie more-consistently with other parts of Australia.
2830 (Thanks to Tim Parenti.)
2833 Release 2013b - 2013-03-10 22:33:40 -0700
2835 Changes affecting current and future timestamps:
2837 Haiti uses US daylight-saving rules this year, and presumably future years.
2838 This changes timestamps starting today. (Thanks to Steffen Thorsen.)
2840 Paraguay will end DST on March 24 this year.
2841 (Thanks to Steffen Thorsen.) For now, assume it's just this year.
2843 Morocco does not observe DST during Ramadan;
2844 try to predict Ramadan in Morocco as best we can.
2845 (Thanks to Erik Homoet for the heads-up.)
2847 Changes affecting commentary:
2849 Update URLs in tz-link page. Add URLs for webOS, BB10, iOS.
2850 Update URL for Solaris. Mention Internet RFC 6557.
2851 Update Internet RFCs 2445->5545, 2822->5322.
2852 Switch from FTP to HTTP for Internet RFCs.
2855 Release 2013a - 2013-02-27 09:20:35 -0800
2857 Change affecting binary data format:
2859 The zone offset at the end of version-2-format zone files is now
2860 allowed to be 24:00, as per POSIX.1-2008. (Thanks to Arthur David Olson.)
2862 Changes affecting current and future timestamps:
2864 Chile's 2013 rules, and we guess rules for 2014 and later, will be
2865 the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
2866 (Thanks to Steffen Thorsen and Robert Elz.)
2868 New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
2869 (Thanks to Tobias Conradi and Arthur David Olson.)
2871 Many changes affect historical timestamps before 1940.
2872 These were deduced from: Milne J. Civil time. Geogr J. 1899
2873 Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
2875 Changes affecting the code:
2877 Fix zic bug that mishandled Egypt's 2010 changes (this also affected
2878 the data). (Thanks to Arthur David Olson.)
2880 Fix localtime bug when time_t is unsigned and data files were generated
2881 by a signed time_t system. (Thanks to Doug Bailey for reporting and
2882 to Arthur David Olson for fixing.)
2884 Allow the email address for bug reports to be set by the packager.
2885 The default is tz@iana.org, as before. (Thanks to Joseph S. Myers.)
2887 Update HTML checking to be compatible with Ubuntu 12.10.
2889 Check that files are a safe subset of ASCII. At some point we may
2890 relax this requirement to a safe subset of UTF-8. Without the
2891 check, some non-UTF-8 encodings were leaking into the distribution.
2895 Restore a comment about copyright notices that was inadvertently deleted.
2896 (Thanks to Arthur David Olson.)
2898 Improve the commentary about which districts observe what times
2899 in Russia. (Thanks to Oscar van Vlijmen and Arthur David Olson).
2901 Add web page links to tz.js.
2903 Add "Run by the Monkeys" to tz-art. (Thanks to Arthur David Olson.)
2906 Release 2012j - 2012-11-12 18:34:49 -0800
2908 Libya moved to CET this weekend, but with DST planned next year.
2909 (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
2911 Signatures now have the extension .asc, not .sign, as that's more
2912 standard. (Thanks to Phil Pennock.)
2914 The output of 'zdump --version', and of 'zic --version', now
2915 uses a format that is more typical for --version.
2916 (Thanks to Joseph S. Myers.)
2918 The output of 'tzselect --help', 'zdump --help', and 'zic --help'
2919 now uses tz@iana.org rather than the old elsie address.
2921 zic -v now complains about abbreviations that are less than 3
2922 or more than 6 characters, as per Posix. Formerly, it checked
2923 for abbreviations that were more than 3.
2925 'make public' no longer puts its temporary directory under /tmp,
2926 and uses the just-built zic rather than the system zic.
2928 Various fixes to documentation and commentary.
2931 Release 2012i - 2012-11-03 12:57:09 -0700
2933 Cuba switches from DST tomorrow at 01:00. (Thanks to Steffen Thorsen.)
2935 Linker flags can now be specified via LDFLAGS.
2936 AWK now defaults to 'awk', not 'nawk'.
2937 The shell in tzselect now defaults to /bin/bash, but this can
2938 be overridden by specifying KSHELL.
2939 The main web page now mentions the unofficial GitHub repository.
2940 (Thanks to Mike Frysinger.)
2942 Tarball signatures can now be built by running 'make signatures'.
2943 There are also new makefile rules 'tarballs', 'check_public', and
2944 separate makefile rules for each tarball and signature file.
2945 A few makefile rules are now more portable to strict POSIX.
2947 The main web page now lists the canonical IANA URL.
2950 Release 2012h - 2012-10-26 22:49:10 -0700
2952 Bahia no longer has DST. (Thanks to Kelley Cook.)
2954 Tocantins has DST. (Thanks to Rodrigo Severo.)
2956 Israel has new DST rules next year. (Thanks to Ephraim Silverberg.)
2958 Jordan stays on DST this winter. (Thanks to Steffen Thorsen.)
2962 More C modernization, except that at Arthur David Olson's suggestion
2963 the instances of 'register' were kept.
2966 Release 2012g - 2012-10-17 20:59:45 -0700
2968 Samoa fall 2012 and later. (Thanks to Nicholas Pereira and Robert Elz.)
2970 Palestine fall 2012. (Thanks to Steffen Thorsen.)
2974 To attack the version-number problem, this release ships the file
2975 'Makefile' (which contains the release number) in both the tzcode and
2976 the tzdata tarballs. The two Makefiles are identical, and should be
2977 identical in any matching pair of tarballs, so it shouldn't matter
2978 which order you extract the tarballs. Perhaps we can come up with a
2979 better version-number scheme at some point; this scheme does have the
2980 virtue of not adding more files.
2983 Release 2012f - 2012-09-12 23:17:03 -0700
2985 * australasia (Pacific/Fiji): Fiji DST is October 21 through January
2986 20 this year. (Thanks to Steffen Thorsen.)
2989 Release 2012e - 2012-08-02 20:44:55 -0700
2991 * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
2992 (Thanks to Steffen Thorsen.)
2994 * Use a single version number for both code and data.
2996 * .gitignore: New file.
2998 * Remove trailing white space.
3001 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
3003 Changes for Morocco's timestamps, which take effect in a couple of
3004 hours, along with infrastructure changes to accommodate how the tz
3005 code and data are released on IANA.
3008 Release data2012c - 2012-03-27 12:17:25 -0400
3011 Summer time changes for Morocco (to start late April 2012)
3014 Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
3017 Haiti following US/Canada rules for 2012 (and we're assuming,
3018 for now anyway, for the future).
3021 Release 2012b - 2012-03-02 12:29:15 +0700
3023 There is just one change to tzcode2012b (compared with 2012a):
3024 the Makefile that was accidentally included with 2012a has been
3025 replaced with the version that should have been there, which is
3026 identical with the previous version (from tzcode2011i).
3028 There are just two changes in tzdata2012b compared with 2012a.
3030 Most significantly, summer time in Cuba has been delayed 3 weeks
3031 (now starts April 1 rather than March 11). Since Mar 11 (the old start
3032 date, as listed in 2012a) is just a little over a week away, this
3035 Less importantly, an excess tab in one of the changes in zone.tab
3036 in 2012a has been removed.
3039 Release 2012a - 2012-03-01 18:28:10 +0700
3041 The changes in tzcode2012a (compared to the previous version, 2011i)
3042 are entirely to the README and tz-art.htm and tz-link.htm files, if
3043 none of those concern you, you can ignore the code update. The changes
3044 reflect the changed addresses for the mailing list and the code and
3045 data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
3046 has been added to tz-link.htm).
3048 In tzdata2012a (compared to the previous release, which was 2011n)
3049 the major changes are:
3050 Chile 2011/2012 and 2012/2013 summer time date adjustments.
3051 Falkland Islands onto permanent summer time (we're assuming for the
3052 foreseeable future, though 2012 is all we're fairly certain of.)
3053 Armenia has abolished Summer Time.
3054 Tokelau jumped the International Date Line back last December
3055 (just the same as their near neighbour, Samoa).
3056 America/Creston is a new zone for a small area of British Columbia
3057 There will be a leapsecond 2012-06-30 23:59:60 UTC.
3059 Other minor changes are:
3060 Corrections to 1918 Canadian summer time end dates.
3061 Updated URL for UK time zone history (in comments)
3062 A few typos in Le Corre's list of free French place names (comments)
3065 Release data2011n - 2011-10-30 14:57:54 +0700
3067 There are three changes of note - most urgently, Cuba (America/Havana)
3068 has extended summer time by two weeks, now to end on Nov 13, rather than
3069 the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic
3070 (Europe/Tiraspol) decided not to split from the rest of Moldova after
3071 all, and consequently that zone has been removed (again) and reinstated
3072 in the "backward" file as a link to Europe/Chisinau. And third, the
3073 end date for Fiji's summer time this summer was moved forward from the
3074 earlier planned Feb 26, to Jan 22.
3076 Apart from that, Moldova (MD) returns to a single entry in zone.tab
3077 (and the incorrect syntax that was in the 2011m version of that file
3078 is so fixed - it would have been fixed in a different way had this
3079 change not happened - that's the "missing" sccs version id).
3082 Release data2011m - 2011-10-24 21:42:16 +0700
3084 In particular, the typos in comments in the data (2011-11-17 should have
3085 been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
3086 Tim Parenti noted) have been fixed, and the change for Ukraine has been
3087 made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
3088 Tim Parenti, and also Denys Gavrysh)
3090 In addition, I added Europe/Tiraspol to zone.tab.
3092 This time, all the files have new version numbers... (including the files
3093 otherwise unchanged in 2011m that were changed in 2011l but didn't get new
3094 version numbers there...)
3097 Release data2011l - 2011-10-10 11:15:43 +0700
3099 There are just 2 changes that cause different generated tzdata files from
3100 zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
3101 is included, but commented out. Compared with the diff I sent out last week,
3102 this version also includes attributions for the sources for the changes
3103 (in much the same format as ado used, but the html tags have not been
3104 checked, verified, or used in any way at all, so if there are errors there,
3105 please let me know.)
3108 Release data2011k - 2011-09-20 17:54:03 -0400
3113 Release data2011j - 2011-09-12 09:22:49 -0400
3115 (contemporary changes for Samoa; past changes for Kenya, Uganda, and
3116 Tanzania); there are also two spelling corrections to comments in
3117 the australasia file (with thanks to Christos Zoulas).
3120 Release 2011i - 2011-08-29 05:56:32 -0400
3125 Release data2011h - 2011-06-15 18:41:48 -0400
3127 Russia and Curaçao changes
3130 Release 2011g - 2011-04-25 09:07:22 -0400
3132 update the rules for Egypt to reflect its abandonment of DST this year
3135 Release 2011f - 2011-04-06 17:14:53 -0400
3140 Release 2011e - 2011-03-31 16:04:38 -0400
3142 Morocco, Chile, and tz-link changes
3145 Release 2011d - 2011-03-14 09:18:01 -0400
3147 changes that impact present-day timestamps in Cuba, Samoa, and Turkey
3150 Release 2011c - 2011-03-07 09:30:09 -0500
3152 These do affect current timestamps in Chile and Annette Island, Canada.
3155 Release 2011b - 2011-02-07 08:44:50 -0500
3160 Release 2011a - 2011-01-24 10:30:16 -0500
3165 Release data2010o - 2010-11-01 09:18:23 -0400
3167 change to the end of DST in Fiji in 2011
3170 Release 2010n - 2010-10-25 08:19:17 -0400
3175 Release 2010m - 2010-09-27 09:24:48 -0400
3177 Hong Kong, Vostok, and zic.c changes
3180 Release 2010l - 2010-08-16 06:57:25 -0400
3185 Release 2010k - 2010-07-26 10:42:27 -0400
3190 Release 2010j - 2010-05-10 09:07:48 -0400
3192 changes for Bahía de Banderas and for version naming
3195 Release data2010i - 2010-04-16 18:50:45 -0400
3197 the end of DST in Morocco on 2010-08-08
3200 Release data2010h - 2010-04-05 09:58:56 -0400
3205 Release data2010g - 2010-03-24 11:14:53 -0400
3210 Release 2010f - 2010-03-22 09:45:46 -0400
3215 Release data2010e - 2010-03-08 14:24:27 -0500
3217 corrects the Dhaka bug found by Danvin Ruangchan
3220 Release data2010d - 2010-03-06 07:26:01 -0500
3225 Release 2010c - 2010-03-01 09:20:58 -0500
3227 changes including KRE's suggestion for earlier initialization of
3228 "goahead" and "goback" structure elements
3231 Release code2010a - 2010-02-16 10:40:04 -0500
3236 Release data2010b - 2010-01-20 12:37:01 -0500
3241 Release data2010a - 2010-01-18 08:30:04 -0500
3246 Release data2009u - 2009-12-26 08:32:28 -0500
3248 changes to DST in Bangladesh
3251 Release 2009t - 2009-12-21 13:24:27 -0500
3256 Release data2009s - 2009-11-14 10:26:32 -0500
3258 (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
3261 Release 2009r - 2009-11-09 10:10:31 -0500
3263 "antarctica" and "tz-link.htm" changes
3266 Release 2009q - 2009-11-02 09:12:40 -0500
3268 with two corrections as reported by Eric Muller and Philip Newton
3271 Release data2009p - 2009-10-23 15:05:27 -0400
3273 Argentina (including San Luis) changes (with the correction from
3277 Release data2009o - 2009-10-14 16:49:38 -0400
3279 Samoa (commentary only), Pakistan, and Bangladesh changes
3282 Release data2009n - 2009-09-22 15:13:38 -0400
3284 added commentary for Argentina and a change to the end of DST in
3288 Release data2009m - 2009-09-03 10:23:43 -0400
3290 Samoa and Palestine changes
3293 Release data2009l - 2009-08-14 09:13:07 -0400
3295 Samoa (comments only) and Egypt
3298 Release 2009k - 2009-07-20 09:46:08 -0400
3303 Release data2009j - 2009-06-15 06:43:59 -0400
3305 Bangladesh change (with a short turnaround since the DST change is
3309 Release 2009i - 2009-06-08 09:21:22 -0400
3311 updating for DST in Bangladesh this year
3314 Release 2009h - 2009-05-26 09:19:14 -0400
3319 Release data2009g - 2009-04-20 16:34:07 -0400
3324 Release data2009f - 2009-04-10 11:00:52 -0400
3326 correct DST in Pakistan
3329 Release 2009e - 2009-04-06 09:08:11 -0400
3334 Release 2009d - 2009-03-23 09:38:12 -0400
3336 Morocco, Tunisia, Argentina, and American Astronomical Society changes
3339 Release data2009c - 2009-03-16 09:47:51 -0400
3341 change to the start of Cuban DST
3344 Release 2009b - 2009-02-09 11:15:22 -0500
3349 Release 2009a - 2009-01-21 10:09:39 -0500
3354 Release data2008i - 2008-10-21 12:10:25 -0400
3356 southamerica and zone.tab files, with Argentina DST rule changes and
3357 United States zone reordering and recommenting
3360 Release 2008h - 2008-10-13 07:33:56 -0400
3365 Release 2008g - 2008-10-06 09:03:18 -0400
3367 Fix a broken HTML anchor and update Brazil's DST transitions;
3368 there's also a slight reordering of information in tz-art.htm.
3371 Release data2008f - 2008-09-09 22:33:26 -0400
3376 Release 2008e - 2008-07-28 14:11:17 -0400
3378 changes by Arthur David Olson and Jesper Nørgaard Welen
3381 Release data2008d - 2008-07-07 09:51:38 -0400
3383 changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
3386 Release data2008c - 2008-05-19 17:48:03 -0400
3388 Pakistan, Morocco, and Mongolia
3391 Release data2008b - 2008-03-24 08:30:59 -0400
3393 including renaming Asia/Calcutta to Asia/Kolkata, with a backward
3397 Release 2008a - 2008-03-08 05:42:16 -0500
3402 Release 2007k - 2007-12-31 10:25:22 -0500
3404 most importantly, changes to the "southamerica" file based on
3405 Argentina's readoption of daylight saving time
3408 Release 2007j - 2007-12-03 09:51:01 -0500
3410 1. eliminate the "P" (parameter) macro;
3412 2. the "noncontroversial" changes circulated on the time zone
3413 mailing list (less the changes to "logwtmp.c");
3415 3. eliminate "too many transition" errors when "min" is used in time
3418 4. changes by Paul Eggert (including updated information for Venezuela).
3421 Release data2007i - 2007-10-30 10:28:11 -0400
3423 changes for Cuba and Syria
3426 Release 2007h - 2007-10-01 10:05:51 -0400
3428 changes by Paul Eggert, as well as an updated link to the ICU
3429 project in tz-link.htm
3432 Release 2007g - 2007-08-20 10:47:59 -0400
3434 changes by Paul Eggert
3436 The "leapseconds" file has been updated to incorporate the most
3437 recent International Earth Rotation and Reference Systems Service
3440 There's an addition to tz-art.htm regarding the television show "Medium".
3443 Release 2007f - 2007-05-07 10:46:46 -0400
3445 changes by Paul Eggert (including Haiti, Turks and Caicos, and New
3448 changes to zic.c to allow hour values greater than 24 (along with
3449 Paul's improved time value overflow checking)
3452 Release 2007e - 2007-04-02 10:11:52 -0400
3454 Syria and Honduras changes by Paul Eggert
3456 zic.c variable renaming changes by Arthur David Olson
3459 Release 2007d - 2007-03-20 08:48:30 -0400
3461 changes by Paul Eggert
3463 the elimination of white space at the ends of lines
3466 Release 2007c - 2007-02-26 09:09:37 -0500
3468 changes by Paul Eggert
3471 Release 2007b - 2007-02-12 09:34:20 -0500
3473 Paul Eggert's proposed change to the quotation handling logic in zic.c.
3475 changes to the commentary in "leapseconds" reflecting the IERS
3476 announcement that there is to be no positive leap second at the end
3480 Release 2007a - 2007-01-08 12:28:29 -0500
3482 changes by Paul Eggert
3484 Derick Rethan's Asmara change
3486 Oscar van Vlijmen's Easter Island local mean time change
3488 symbolic link changes
3491 Release 2006p - 2006-11-27 08:54:27 -0500
3493 changes by Paul Eggert
3496 Release 2006o - 2006-11-06 09:18:07 -0500
3498 changes by Paul Eggert
3501 Release 2006n - 2006-10-10 11:32:06 -0400
3503 changes by Paul Eggert
3506 Release 2006m - 2006-10-02 15:32:35 -0400
3508 changes for Uruguay, Palestine, and Egypt by Paul Eggert
3510 (minimalist) changes to zic.8 to clarify "until" information
3513 Release data2006l - 2006-09-18 12:58:11 -0400
3515 Paul's best-effort work on this coming weekend's Egypt time change
3518 Release 2006k - 2006-08-28 12:19:09 -0400
3520 changes by Paul Eggert
3523 Release 2006j - 2006-08-21 09:56:32 -0400
3525 changes by Paul Eggert
3528 Release code2006i - 2006-08-07 12:30:55 -0400
3532 Ken Pizzini's conversion script
3535 Release code2006h - 2006-07-24 09:19:37 -0400
3537 adds public domain notices to four files
3539 includes a fix for transition times being off by a second
3541 adds a new recording to the "arts" file (information courtesy Colin Bowern)
3544 Release 2006g - 2006-05-08 17:18:09 -0400
3546 northamerica changes by Paul Eggert
3549 Release 2006f - 2006-05-01 11:46:00 -0400
3551 a missing version number problem is fixed (with thanks to Bradley
3552 White for catching the problem)
3555 Release 2006d - 2006-04-17 14:33:43 -0400
3557 changes by Paul Eggert
3559 added new items to tz-arts.htm that were found by Paul
3562 Release 2006c - 2006-04-03 10:09:32 -0400
3564 two sets of data changes by Paul Eggert
3566 a fencepost error fix in zic.c
3568 changes to zic.c and the "europe" file to minimize differences
3569 between output produced by the old 32-bit zic and the new 64-bit
3573 Release 2006b - 2006-02-20 10:08:18 -0500
3574 [tz32code2006b + tz64code2006b + tzdata2006b]
3578 All SCCS IDs were bumped to "8.1" for this release.
3581 Release 2006a - 2006-01-30 08:59:31 -0500
3583 changes by Paul Eggert (in particular, Indiana time zone moves)
3585 an addition to the zic manual page to describe how special-case
3586 transitions are handled
3589 Release 2005r - 2005-12-27 09:27:13 -0500
3591 Canadian changes by Paul Eggert
3593 They also add "<pre>" directives to time zone data files and reflect
3594 changes to warning message logic in "zdump.c" (but with calls to
3595 "gettext" kept unbundled at the suggestion of Ken Pizzini).
3598 Release 2005q - 2005-12-13 09:17:09 -0500
3600 Nothing earth-shaking here:
3601 1. Electronic mail addresses have been removed.
3602 2. Casts of the return value of exit have been removed.
3603 3. Casts of the argument of is.* macros have been added.
3604 4. Indentation in one section of zic.c has been fixed.
3605 5. References to dead URLs in the data files have been dealt with.
3608 Release 2005p - 2005-12-05 10:30:53 -0500
3610 "systemv", "tz-link.htm", and "zdump.c" changes
3611 (less the casts of arguments to the is* macros)
3614 Release 2005o - 2005-11-28 10:55:26 -0500
3616 Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
3618 zdump.c lint fixes by Arthur David Olson
3621 Release 2005n - 2005-10-03 09:44:09 -0400
3623 changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
3627 Release 2005m - 2005-08-29 12:15:40 -0400
3629 changes by Paul Eggert (with a small tweak to the tz-art change)
3631 a declaration of an unused variable has been removed from zdump.c
3634 Release 2005l - 2005-08-22 12:06:39 -0400
3636 changes by Paul Eggert
3638 overflow/underflow checks by Arthur David Olson, minus changes to
3639 the "Theory" file about the pending addition of 64-bit data (I grow
3640 less confident of the changes being accepted with each passing day,
3641 and the changes no longer increase the data files nine-fold--there's
3642 less than a doubling in size by my local Sun's reckoning)
3645 Release 2005k - 2005-07-14 14:14:24 -0400
3647 The "leapseconds" file has been edited to reflect the recently
3648 announced leap second at the end of 2005.
3650 I've also deleted electronic mail addresses from the files as an
3654 Release 2005j - 2005-06-13 14:34:13 -0400
3656 These reflect changes to limit the length of time zone abbreviations
3657 and the characters used in those abbreviations.
3659 There are also changes to handle POSIX-style "quoted" timezone
3660 environment variables.
3662 The changes were circulated on the time zone mailing list; the only
3663 change since then was the removal of a couple of minimum-length of
3664 abbreviation checks.
3667 Release data2005i - 2005-04-21 15:04:16 -0400
3669 changes (most importantly to Nicaragua and Haiti) by Paul Eggert
3672 Release 2005h - 2005-04-04 11:24:47 -0400
3674 changes by Paul Eggert
3676 minor changes to Makefile and zdump.c to produce more useful output
3677 when doing a "make typecheck"
3680 Release 2005g - 2005-03-14 10:11:21 -0500
3682 changes by Paul Eggert (a change to current DST rules in Uruguay and
3683 an update to a link to time zone software)
3686 Release 2005f - 2005-03-01 08:45:32 -0500
3688 data and documentation changes by Paul Eggert
3691 Release 2005e - 2005-02-10 15:59:44 -0500
3696 Release code2005d - 2005-01-31 09:21:47 -0500
3698 make zic complain about links to links if the -v flag is used
3700 have "make public" do more code checking
3702 add an include to "localtime.c" for the benefit of gcc systems
3705 Release 2005c - 2005-01-17 18:36:29 -0500
3707 get better results when mktime runs on a system where time_t is double
3709 changes to the data files (most importantly to Paraguay)
3712 Release 2005b - 2005-01-10 09:19:54 -0500
3714 Get localtime and gmtime working on systems with exotic time_t types.
3716 Update the leap second commentary in the "leapseconds" file.
3719 Release 2005a - 2005-01-01 13:13:44 -0500
3724 Release code2004i - 2004-12-14 13:42:58 -0500
3726 Deal with systems where time_t is unsigned.
3729 Release code2004h - 2004-12-07 11:40:18 -0500
3731 64-bit-time_t changes
3734 Release 2004g - 2004-11-02 09:06:01 -0500
3736 update to Cuba (taking effect this weekend)
3738 other changes by Paul Eggert
3740 correction of the spelling of Oslo
3742 changed versions of difftime.c and private.h
3745 Release code2004f - 2004-10-21 10:25:22 -0400
3747 Cope with wide-ranging tm_year values.
3750 Release 2004e - 2004-10-11 14:47:21 -0400
3752 Brazil/Argentina/Israel changes by Paul Eggert
3754 changes to tz-link.htm by Paul
3756 one small fix to Makefile
3759 Release 2004d - 2004-09-22 08:27:29 -0400
3761 Avoid overflow problems when TM_YEAR_BASE is added to an integer.
3764 Release 2004c - 2004-08-11 12:06:26 -0400
3766 asctime-related changes
3768 (variants of) some of the documentation changes suggested by Paul Eggert
3771 Release 2004b - 2004-07-19 14:33:35 -0400
3773 data changes by Paul Eggert - most importantly, updates for Argentina
3776 Release 2004a - 2004-05-27 12:00:47 -0400
3778 changes by Paul Eggert
3780 Handle DST transitions that occur at the end of a month in some
3781 years but at the start of the following month in other years.
3783 Add a copy of the correspondence that's the basis for claims about
3784 DST in the Navajo Nation.
3787 Release 2003e - 2003-12-15 09:36:47 -0500
3789 changes by Arthur David Olson (primarily code changes)
3791 changes by Paul Eggert (primarily data changes)
3793 minor changes to "Makefile" and "northamerica" (in the latter case,
3794 optimization of the "Toronto" rules)
3797 Release 2003d - 2003-10-06 09:34:44 -0400
3799 changes by Paul Eggert
3802 Release 2003c - 2003-09-16 10:47:05 -0400
3804 Fix bad returns in zic.c's inleap function.
3805 Thanks to Bradley White for catching the problem!
3808 Release 2003b - 2003-09-16 07:13:44 -0400
3810 Add a "--version" option (and documentation) to the zic and zdump commands.
3812 changes to overflow/underflow checking in zic
3814 a localtime typo fix.
3816 Update the leapseconds and tz-art.htm files.
3819 Release 2003a - 2003-03-24 09:30:54 -0500
3821 changes by Paul Eggert
3823 a few additions and modifications to the tz-art.htm file
3826 Release 2002d - 2002-10-15 13:12:42 -0400
3828 changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
3830 There's also a new time zone quote in "tz-art.htm".
3833 Release 2002c - 2002-04-04 11:55:20 -0500
3835 changes by Paul Eggert
3837 Change zic.c to avoid creating symlinks to files that don't exist.
3840 Release 2002b - 2002-01-28 12:56:03 -0500
3842 [These change notes are for Release 2002a, which was corrupted.
3843 2002b was a corrected version of 2002a.]
3845 changes by Paul Eggert
3847 Update the "leapseconds" file to note that there'll be no leap
3848 second at the end of June, 2002.
3850 Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
3852 Change to "difftime.c" to avoid sizeof problems.
3855 Release 2001d - 2001-10-09 13:31:32 -0400
3857 changes by Paul Eggert
3860 Release 2001c - 2001-06-05 13:59:55 -0400
3862 changes by Paul Eggert and Andrew Brown
3865 Release 2001b - 2001-04-05 16:44:38 -0400
3867 changes by Paul Eggert (modulo jnorgard's typo fix)
3869 tz-art.htm has been HTMLified.
3872 Release 2001a - 2001-03-13 12:57:44 -0500
3874 changes by Paul Eggert
3876 An addition to the "leapseconds" file: comments with the text of the
3877 latest IERS leap second notice.
3879 Trailing white space has been removed from data file lines, and
3880 repeated spaces in "Rule Jordan" lines in the "asia" file have been
3884 Release 2000h - 2000-12-14 15:33:38 -0500
3886 changes by Paul Eggert
3888 one typo fix in the "art" file
3890 With providence, this is the last update of the millennium.
3893 Release 2000g - 2000-10-10 11:35:22 -0400
3895 changes by Paul Eggert
3897 correction of John Mackin's name submitted by Robert Elz
3899 Garry Shandling's Daylight Saving Time joke (!?!) from the recent
3900 Emmy Awards broadcast.
3903 Release 2000f - 2000-08-10 09:31:58 -0400
3905 changes by Paul Eggert
3907 Added information in "tz-art.htm" on a Seinfeld reference to DST.
3909 Error checking and messages in the "yearistype" script have been
3913 Release 2000e - 2000-07-31 09:27:54 -0400
3915 data changes by Paul Eggert
3917 a change to the default value of the defined constant HAVE_STRERROR
3919 the addition of a Dave Barry quote on DST to the tz-arts file
3922 Release 2000d - 2000-04-20 15:43:04 -0400
3924 changes to the documentation and code of strftime for C99 conformance
3926 a bug fix for date.c
3928 These are based on (though modified from) changes by Paul Eggert.
3931 Release 2000c - 2000-03-04 10:31:43 -0500
3933 changes by Paul Eggert
3936 Release 2000b - 2000-02-21 12:16:29 -0500
3938 changes by Paul Eggert and Joseph Myers
3940 modest tweaks to the tz-art.htm and tz-link.htm files
3943 Release 2000a - 2000-01-18 09:21:26 -0500
3945 changes by Paul Eggert
3947 The two hypertext documents have also been renamed.
3950 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
3952 Paul Eggert's changes
3954 additions to the "zic" manual page and the "Arts.htm" file
3957 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
3962 Release data1999h - 1999-10-07 03:50:29 -0400
3964 changes by Paul Eggert to "europe" (most importantly, fixing
3965 Lithuania and Estonia)
3968 Release 1999g - 1999-09-28 11:06:18 -0400
3970 data changes by Paul Eggert (most importantly, the change for
3971 Lebanon that buys correctness for this coming Sunday)
3973 The "code" file contains changes to "Makefile" and "checktab.awk" to
3974 allow better checking of time zone files before they are published.
3977 Release 1999f - 1999-09-23 09:48:14 -0400
3979 changes by Arthur David Olson and Paul Eggert
3982 Release 1999e - 1999-08-17 15:20:54 -0400
3984 changes circulated by Paul Eggert, although the change to handling
3985 of DST-specifying timezone names has been commented out for now
3986 (search for "XXX" in "localtime.c" for details). These files also
3987 do not make any changes to the start of DST in Brazil.
3989 In addition to Paul's changes, there are updates to "Arts.htm" and
3993 Release 1999d - 1999-03-30 11:31:07 -0500
3995 changes by Paul Eggert
3997 The Makefile's "make public" rule has also been changed to do a test
3998 compile of each individual time zone data file (which should help
3999 avoid problems such as the one we had with Nicosia).
4002 Release 1999c - 1999-03-25 09:47:47 -0500
4004 changes by Paul Eggert, most importantly the change for Chile.
4007 Release 1999b - 1999-02-01 17:51:44 -0500
4009 changes by Paul Eggert
4011 code changes (suggested by Mani Varadarajan, mani at be.com) for
4012 correct handling of symbolic links when building using a relative directory
4014 code changes to generate correct messages for failed links
4016 updates to the URLs in Arts.htm
4019 Release 1999a - 1999-01-19 16:20:29 -0500
4021 error message internationalizations and corrections in zic.c and
4022 zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
4026 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
4028 changes for Brazil, Chile, and Germany
4030 support for use of "24:00" in the input files for the time zone compiler
4033 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
4035 changes by Paul Eggert
4037 correction to a define in the "private.h" file
4040 Release data1998g - 1998-08-11 03:28:35 -0000
4041 [tzdata1998g.tar.gz is missing!]
4043 Lithuanian change provided by mgedmin at pub.osf.it
4045 Move creation of the GMT link with Etc/GMT to "etcetera" (from
4046 "backward") to ensure that the GMT file is created even where folks
4047 don't want the "backward" links (as suggested by Paul Eggert).
4050 Release data1998f - 1998-07-20 13:50:00 -0000
4051 [tzdata1998f.tar.gz is missing!]
4053 Update the "leapseconds" file to include the newly-announced
4054 insertion at the end of 1998.
4057 Release code1998f - 1998-06-01 10:18:31 -0400
4059 addition to localtime.c by Guy Harris
4062 Release 1998e - 1998-05-28 09:56:26 -0400
4064 The Makefile is changed to produce zoneinfo-posix rather than
4065 zoneinfo/posix, and to produce zoneinfo-leaps rather than
4068 data changes by Paul Eggert
4070 changes from Guy Harris to provide asctime_r and ctime_r
4072 A usno1998 file (substantially identical to usno1997) has been added.
4075 Release 1998d - 1998-05-14 11:58:34 -0400
4077 changes to comments (in particular, elimination of references to CIA maps).
4078 "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
4079 where changes occur.
4082 Release 1998c - 1998-02-28 12:32:26 -0500
4084 changes by Paul Eggert (save the "French correction," on which I'll
4085 wait for the dust to settle)
4089 changes and additions to Arts.htm
4092 Release 1998b - 1998-01-17 14:31:51 -0500
4094 URL cleanups and additions
4097 Release 1998a - 1998-01-13 12:37:35 -0500
4099 changes by Paul Eggert
4102 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
4104 changes by Paul Eggert, with minor modifications from Arthur David
4105 Olson to make the files more browser friendly
4108 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
4110 minor changes to put "TZif" at the start of each timezone information file
4112 a rule has also been added to the Makefile so you can
4114 to just recompile the zone information files (rather than doing a
4115 full "make install" with its other effects).
4118 Release data1997i - 1997-10-07 08:45:38 -0400
4120 changes to Africa by Paul Eggert
4123 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
4125 corrections for Uruguay (and other locations)
4127 Arthur David Olson's simple-minded fix allowing mktime to both
4128 correctly handle leap seconds and correctly handle tm_sec values
4129 upon which arithmetic has been performed.
4132 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
4134 Paul Eggert's updates
4136 a small change to a function prototype;
4138 "Music" has been renamed "Arts.htm", HTMLified, and augmented to
4139 include information on Around the World in Eighty Days.
4142 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
4144 fixes to zic's error handling
4146 changes inspired by the item circulated on Slovenia
4148 The description of Web resources has been HTMLified for browsing
4151 A new piece of tz-related music has been added to the "Music" file.
4154 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
4156 Paul Eggert's latest suggestions
4159 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
4161 changes to "zic.c" to correct performance of the "-s" option
4163 a new file "usno1997"
4166 Release data1997c - 1997-03-04 09:58:18 -0500
4171 Release 1997b - 1997-02-27 18:34:19 -0500
4173 The data file incorporates the 1997 leap second.
4175 The code file incorporates Arthur David Olson's take on the
4176 zic/multiprocessor/directory-creation situation.
4179 Release 1997a - 1997-01-21 09:11:10 -0500
4181 Paul Eggert's Antarctica (and other changes)
4183 Arthur David Olson finessed the "getopt" issue by checking against
4184 both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
4185 is returned while SunOS 5.5's manual says EOF is returned).
4188 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
4190 Paul Eggert's latest changes
4193 Release code1996n - 1996-12-16 09:42:02 -0500
4195 link snapping fix from Bruce Evans (via Garrett Wollman)
4198 Release data1996m - 1996-11-24 02:37:34 -0000
4199 [tzdata1996m.tar.gz is missing!]
4201 Paul Eggert's batch of changes
4204 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
4206 No functional changes here; the files have simply been changed to
4207 make more use of ISO style dates in comments. The names of the above
4208 files now include the year in full.
4211 Release code96l - 1996-09-08 17:12:20 -0400
4213 tzcode96k was missing a couple of pieces.
4216 Release 96k - 1996-09-08 16:06:22 -0400
4218 the latest round of changes from Paul Eggert
4220 the recent Year 2000 material
4223 Release code96j - 1996-07-30 13:18:53 -0400
4225 Set sp->typecnt as suggested by Timothy Patrick Murphy.
4228 Release code96i - 1996-07-27 20:11:35 -0400
4230 Paul's suggested patch for strftime %V week numbers
4233 Release data96i - 1996-07-01 18:13:04 -0400
4235 "northamerica" and "europe" changes by Paul Eggert
4238 Release code96h - 1996-06-05 08:02:21 -0400
4240 fix for handling transitions specified in Universal Time
4242 Some "public domain" notices have also been added.
4245 Release code96g - 1996-05-16 14:00:26 -0400
4247 fix for the simultaneous-DST-and-zone-change challenge
4250 Release data96h - 1996-05-09 17:40:51 -0400
4252 changes by Paul Eggert
4255 Release code96f-data96g - 1996-05-03 03:09:59 -0000
4256 [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
4258 The changes get us some of the way to fixing the problems noted in Paul
4259 Eggert's letter yesterday (in addition to a few others). The approach
4260 has been to make zic a bit smarter about figuring out what time zone
4261 abbreviations apply just after the time specified in the "UNTIL" part
4262 of a zone line. Putting the smarts in zic means avoiding having
4263 transition times show up in both "Zone" lines and "Rule" lines, which
4264 in turn avoids multiple transition time entries in time zone files.
4265 (This also makes the zic input files such as "europe" a bit shorter and
4266 should ease maintenance.)
4269 Release data96f - 1996-04-19 19:20:03 -0000
4270 [tzdata96f.tar.gz is missing!]
4272 The only changes are to the "northamerica" file; the time zone
4273 abbreviation for Denver is corrected to MST (and MDT), and the
4274 comments for Mexico have been updated.
4277 Release data96e - 1996-03-19 17:37:26 -0500
4279 Proposals by Paul Eggert, in particular the Portugal change that
4280 comes into play at the end of this month.
4283 Release data96d - 1996-03-18 20:49:39 -0500
4288 Release code96e - 1996-02-29 15:43:27 -0000
4289 [tzcode96e.tar.gz is missing!]
4291 internationalization changes and the fix to the documentation for strftime
4294 Release code96d-data96c - 1996-02-12 11:05:27 -0500
4296 The "code" file simply updates Bob Kridle's electronic address.
4298 The "data" file updates rules for Mexico.
4301 Release data96b - 1996-01-27 15:44:42 -0500
4306 Release code96c - 1996-01-16 16:58:15 -0500
4308 leap-year streamlining and binary-search changes
4313 Release code96b - 1996-01-10 20:42:39 -0500
4315 fixes and enhancements from Paul Eggert, including code that
4316 emulates the behavior of recent versions of the SunOS "date"
4320 Release 96a - 1996-01-06 09:08:24 -0500
4324 fixes to strftime.c for correct ISO 8601 week number generation,
4325 plus support for two new formats ('G' and 'g') to give ISO 8601 year
4326 numbers (which are not necessarily the same as calendar year numbers)
4329 Release code95i-data95m - 1995-12-21 12:46:47 -0500
4331 The latest revisions from Paul Eggert are included, the usno1995
4332 file has been updated, and a new file ("WWW") covering useful URLs
4336 Release code95h-data95l - 1995-12-19 18:10:12 -0500
4338 A simplification of a macro definition, a change to data for Sudan,
4339 and (for last minute shoppers) notes in the "Music" file on the CD
4343 Release code95g-data95k - 1995-10-30 10:32:47 -0500
4345 (slightly reformatted) 8-bit-clean proposed patch
4347 minor patch: US/Eastern -> America/New_York
4349 snapshot of the USNO's latest data ("usno1995")
4351 some other minor cleanups
4354 Release code95f-data95j - 1995-10-28 21:01:34 -0000
4355 [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
4359 support for 64-bit time_t's
4361 optimization in localtime.c
4364 Release code95e - 1995-10-13 13:23:57 -0400
4366 the mktime change to scan from future to past when trying to find time zone
4370 Release data95i - 1995-09-26 10:43:26 -0400
4372 For Canada/Central, guess that the Sun customer's "one week too
4373 early" was just a approximation, and the true error is one month
4374 too early. This is consistent with the rest of Canada.
4377 Release data95h - 1995-09-21 11:26:48 -0400
4379 latest changes from Paul Eggert
4382 Release code95d - 1995-09-14 11:14:45 -0400
4384 the addition of a "Music" file, which documents four recorded
4385 versions of the tune "Save That Time".
4388 Release data95g - 1995-09-01 17:21:36 -0400
4390 "yearistype" correction
4393 Release data95f - 1995-08-28 20:46:56 -0400
4395 Paul Eggert's change to the australasia file
4398 Release data95e - 1995-07-08 18:02:34 -0400
4400 The only change is a leap second at the end of this year.
4401 Thanks to Bradley White for forwarding news on the leap second.
4404 Release data95d - 1995-07-03 13:26:22 -0400
4406 Paul Eggert's changes
4409 Release data95c - 1995-07-02 19:19:28 -0400
4411 changes to "asia", "backward", "europe", and "southamerica"
4412 (read: northamericacentrics need not apply)
4415 Release code95c - 1995-03-13 14:00:46 -0500
4417 one-line fix for sign extension problems in detzcode
4420 Release 95b - 1995-03-04 11:22:38 -0500
4422 Minor changes in both:
4424 The "code" file contains a workaround for the lack of "unistd.h" in
4425 Microsoft C++ version 7.
4427 The "data" file contains a fixed "Link" for America/Shiprock.
4430 Release 94h - 1994-12-10 12:51:14 -0500
4434 * incorporate the changes to "zdump" and "date" to make changes to
4435 the "TZ" environment variable permanent;
4437 * incorporate the table changes by Paul Eggert;
4439 * include (and document) support for universal time specifications in
4440 data files - but do not (yet) include use of this feature in the
4443 Think of this as "TZ Classic" - the software has been set up not to break if
4444 universal time shows up in its input, and data entries have been
4445 left as is so as not to break existing implementations.
4448 Release data94f - 1994-08-20 12:56:09 -0400
4450 (with thanks!) the latest data updates from Paul Eggert
4453 Release data94e - 1994-06-04 13:13:53 -0400
4458 Release code94g - 1994-05-05 12:14:07 -0400
4460 fix missing "optind.c" and a reference to it in the Makefile
4463 Release code94f - 1994-05-05 13:00:33 -0000
4464 [tzcode94f.tar.gz is missing!]
4466 changes to avoid overflow in difftime, as well as changes to cope
4467 with the 52/53 challenge in strftime
4470 Release code94e - 1994-03-30 23:32:59 -0500
4472 change for the benefit of PCTS
4475 Release 94d - 1994-02-24 15:42:25 -0500
4477 Avoid clashes with POSIX semantics for zones such as GMT+4.
4479 Some other very minor housekeeping is also present.
4482 Release code94c - 1994-02-10 08:52:40 -0500
4484 Fix bug where mkdirs was broken unless you compile with
4485 -fwritable-strings (which is generally losing to do).
4488 Release 94b - 1994-02-07 10:04:33 -0500
4490 work by Paul Eggert who notes:
4492 I found another book of time zone histories by E W Whitman; it's not
4493 as extensive as Shanks but has a few goodies of its own. I used it
4494 to update the tables. I also fixed some more as a result of
4495 correspondence with Adam David and Peter Ilieve, and move some stray
4496 links from 'europe' to 'backward'. I corrected some scanning errors
4499 As far as the code goes, I fixed zic to allow years in the range
4500 INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
4501 And I cleaned up the zic documentation a little bit.
4504 Release data94a - 1994-02-03 08:58:54 -0500
4506 It simply incorporates the recently announced leap second into the
4510 Release 93g - 1993-11-22 17:28:27 -0500
4512 Paul Eggert has provided a good deal of historic information (based
4513 on Shanks), and there are some code changes to deal with the buglets
4514 that crawled out in dealing with the new information.
4517 Release 93f - 1993-10-15 12:27:46 -0400
4519 Paul Eggert's changes
4522 Release 93e - 1993-09-05 21:21:44 -0400
4524 This has updated data for Israel, England, and Kwajalein. There's
4525 also an update to "zdump" to cope with Kwajalein's 24-hour jump.
4526 Thanks to Paul Eggert and Peter Ilieve for the changes.
4529 Release 93d - 1993-06-17 23:34:17 -0400
4531 new fix and new data on Israel
4534 Release 93c - 1993-06-06 19:31:55 -0400
4539 Release 93b - 1993-02-02 14:53:58 -0500
4541 updated "leapseconds" file
4544 Release 93 - 1993-01-08 07:01:06 -0500
4546 At kre's suggestion, the package has been split in two - a code piece
4547 (which also includes documentation) that's only of use to folks who
4548 want to recompile things and a data piece useful to anyone who can
4551 The new version has a few changes to the data files, a few
4552 portability changes, and an off-by-one fix (with thanks to
4553 Tom Karzes at deshaw.com for providing a description and a
4557 Release 92c - 1992-11-21 17:35:36 -0000
4558 [tz92c.tar.Z is missing!]
4560 The fallout from the latest round of DST transitions.
4562 There are changes for Portugal, Saskatchewan, and "Pacific-New";
4563 there's also a change to "zic.c" that makes it portable to more systems.
4566 Release 92 - 1992-04-25 18:17:03 -0000
4567 [tz92.tar.Z is missing!]
4569 By popular demand (well, at any rate, following a request by kre at munnari)
4572 The 1989 update of the time zone package featured:
4574 * POSIXization (including interpretation of POSIX-style TZ environment
4575 variables, provided by Guy Harris),
4576 * ANSIfication (including versions of "mktime" and "difftime"),
4577 * SVIDulation (an "altzone" variable)
4578 * MACHination (the "gtime" function)
4579 * corrections to some time zone data (including corrections to the rules
4580 for Great Britain and New Zealand)
4581 * reference data from the United States Naval Observatory for folks who
4582 want to do additional time zones
4583 * and the 1989 data for Saudi Arabia.
4585 (Since this code will be treated as "part of the implementation" in some
4586 places and as "part of the application" in others, there's no good way to
4587 name functions, such as timegm, that are not part of the proposed ANSI C
4588 standard; such functions have kept their old, underscore-free names in this
4591 And the "dysize" function has disappeared; it was present to allow
4592 compilation of the "date" command on old BSD systems, and a version of "date"
4593 is now provided in the package. The "date" command is not created when you
4594 "make all" since it may lack options provided by the version distributed with
4595 your operating system, or may not interact with the system in the same way
4596 the native version does.
4598 Since POSIX frowns on correct leap second handling, the default behavior of
4599 the "zic" command (in the absence of a "-L" option) has been changed to omit
4600 leap second information from its output files.
4606 This file contains copies of the part of each release announcement
4607 that talks about the changes in that release. The text has been
4608 adapted and reformatted for the purposes of this file.
4610 Traditionally a release R consists of a pair of tarball files,
4611 tzcodeR.tar.gz and tzdataR.tar.gz. However, some releases (e.g.,
4612 code2010a, data2012c) consist of just one or the other tarball, and a
4613 few (e.g., code2012c-data2012d) have tarballs with mixed version
4614 numbers. Recent releases also come in an experimental format
4615 consisting of a single tarball tzdb-R.tar.lz with extra data.
4617 Release timestamps are taken from the release's commit (for newer,
4618 Git-based releases), from the newest file in the tarball (for older
4619 releases, where this info is available) or from the email announcing
4620 the release (if all else fails; these are marked with a time zone
4621 abbreviation of -0000 and an "is missing!" comment).
4623 Earlier versions of the code and data were not announced on the tz
4624 list and are not summarized here.
4626 This file is in the public domain.