xref: /dragonfly/share/zoneinfo/NEWS (revision d4ef6694)

News for the tz database

Release 2014j - 2014-11-10 17:37:11 -0800

  Changes affecting current and future time stamps

    Turks & Caicos' switch from US eastern time to UTC-4 year-round
    did not occur on 2014-11-02 at 02:00.  It's currently scheduled
    for 2015-11-01 at 02:00.  (Thanks to Chris Walton.)

  Changes affecting past time stamps

    Many pre-1989 time stamps have been corrected for Asia/Seoul and
    Asia/Pyongyang, based on sources for the Korean-language Wikipedia
    entry for time in Korea.  (Thanks to Sanghyuk Jung.)  Also, no
    longer guess that Pyongyang mimicked Seoul time after World War II,
    as this is politically implausible.

    Some more zones have been turned into links, when they differed
    from existing zones only for older time stamps.  As usual,
    these changes affect UTC offsets in pre-1970 time stamps only.
    Their old contents have been moved to the 'backzone' file.
    The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
    Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
    Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
    Indian/Mayotte.

  Changes affecting commentary

    The commentary is less enthusiastic about Shanks as a source,
    and is more careful to distinguish UT from UTC.


Release 2014i - 2014-10-21 22:04:57 -0700

  Changes affecting future time stamps

    Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
    (Thanks to Ken Rylander for the heads-up.)  Guess that future
    years will use a similar pattern.

    A new Zone Pacific/Bougainville, for the part of Papua New Guinea
    that plans to switch from UTC+10 to UTC+11 on 2014-12-28 at 02:00.
    (Thanks to Kiley Walbom for the heads-up.)

  Changes affecting time zone abbreviations

    Since Belarus is not changing its clocks even though Moscow is,
    the time zone abbreviation in Europe/Minsk is changing from FET
    to its more-traditional value MSK on 2014-10-26 at 01:00.
    (Thanks to Alexander Bokovoy for the heads-up about Belarus.)

    The new abbreviation IDT stands for the pre-1976 use of UT+8 in
    Indochina, to distinguish it better from ICT (UT+7).

  Changes affecting past time stamps

    Many time stamps have been corrected for Asia/Ho_Chi_Minh before 1976
    (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
    authoritative book).  Asia/Ho_Chi_Minh has been added to
    zone1970.tab, to give tzselect users in Vietnam two choices,
    since north and south Vietnam disagreed after our 1970 cutoff.

    Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
    they differed from existing zones only for older time stamps.  As
    usual, these changes affect pre-1970 time stamps only.  Their old
    contents have been moved to the 'backzone' file.

  Changes affecting code

    The time-related library functions now set errno on failure, and
    some crashes in the new tzalloc-related library functions have
    been fixed.  (Thanks to Christos Zoulas for reporting most of
    these problems and for suggesting fixes.)

    If USG_COMPAT is defined and the requested time stamp is standard time,
    the tz library's localtime and mktime functions now set the extern
    variable timezone to a value appropriate for that time stamp; and
    similarly for ALTZONE, daylight saving time, and the altzone variable.
    This change is a companion to the tzname change in 2014h, and is
    designed to make timezone and altzone more compatible with tzname.

    The tz library's functions now set errno to EOVERFLOW if they fail
    because the result cannot be represented.  ctime and ctime_r now
    return NULL and set errno when a time stamp is out of range, rather
    than having undefined behavior.

    Some bugs associated with the new 2014g functions have been fixed.
    This includes a bug that largely incapacitated the new functions
    time2posix_z and posix2time_z.  (Thanks to Christos Zoulas.)
    It also includes some uses of uninitialized variables after tzalloc.
    The new code uses the standard type 'ssize_t', which the Makefile
    now gives porting advice about.

  Changes affecting commentary

    Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).


Release 2014h - 2014-09-25 18:59:03 -0700

  Changes affecting past time stamps

    America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.

    Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
    not 1920-01-06.  The old entry was based on a misinterpretation of Shanks.

    Some more zones have been turned into links, when they differed
    from existing zones only for older time stamps.  As usual,
    these changes affect UTC offsets in pre-1970 time stamps only.
    Their old contents have been moved to the 'backzone' file.
    The affected zones are: Africa/Blantyre, Africa/Bujumbura,
    Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
    Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.

  Changes affecting code

    zdump -V and -v now output gmtoff= values on all platforms,
    not merely on platforms defining TM_GMTOFF.

    The tz library's localtime and mktime functions now set tzname to a value
    appropriate for the requested time stamp, and zdump now uses this
    on platforms not defining TM_ZONE, fixing a 2014g regression.
    (Thanks to Tim Parenti for reporting the problem.)

    The tz library no longer sets tzname if localtime or mktime fails.

    zdump -c no longer mishandles transitions near year boundaries.
    (Thanks to Tim Parenti for reporting the problem.)

    An access to uninitalized data has been fixed.
    (Thanks to Jörg Richter for reporting the problem.)

    When THREAD_SAFE is defined, the code ports to the C11 memory model.
    A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
    and two threads race to initialize data used by gmtime-like functions.
    (Thanks to Andy Heninger for reporting the problems.)

  Changes affecting build procedure

    'make check' now checks better for properly-sorted data.

  Changes affecting documentation and commentary

    zdump's gmtoff=N output is now documented, and its isdst=D output
    is now documented to possibly output D values other than 0 or 1.

    zdump -c's treatment of years is now documented to use the
    Gregorian calendar and Universal Time without leap seconds,
    and its behavior at cutoff boundaries is now documented better.
    (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)

    Programs are now documented to use the proleptic Gregorian calendar.
    (Thanks to Alan Barrett for the suggestion.)

    Fractional-second GMT offsets have been documented for civil time
    in 19th-century Chennai, Jakarta, and New York.


Release 2014g - 2014-08-28 12:31:23 -0700

  Changes affecting future time stamps

    Turks & Caicos is switching from US eastern time to UTC-4 year-round,
    modeled as a switch from EST/EDT to AST on 2014-11-02 at 02:00.
    [As noted in 2014j, this switch was later delayed.]

  Changes affecting past time stamps

    Time in Russia or the USSR before 1926 or so has been corrected by
    a few seconds in the following zones: Asia/Irkutsk,
    Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
    Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara.  For
    Asia/Yekaterinburg the correction is a few minutes.  (Thanks to
    Vladimir Karpinsky.)

    The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
    This affects 1911 time stamps in Africa/Bissau, Africa/Luanda,
    Atlantic/Azores, and Atlantic/Madeira.  Also, Lisbon's pre-1912
    GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
    (Thanks to Stephen Colebourne for pointing to the decree.)

    Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.

    A new file 'backzone' contains data which may appeal to
    connoisseurs of old time stamps, although it is out of scope for
    the tz database, is often poorly sourced, and contains some data
    that is known to be incorrect.  The new file is not recommended
    for ordinary use and its entries are not installed by default.
    (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
    Isle of Man entries.)

    Some more zones have been turned into links, when they differed
    from existing zones only for older time stamps.  As usual,
    these changes affect UTC offsets in pre-1970 time stamps only.
    Their old contents have been moved to the 'backzone' file.
    The affected zones are: Africa/Bangui, Africa/Brazzaville,
    Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
    Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.

  Changes affecting code

    Unless NETBSD_INSPIRED is defined to 0, the tz library now
    supplies functions for creating and using objects that represent
    time zones. The new functions are tzalloc, tzfree, localtime_rz,
    mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
    time2posix_z.  They are intended for performance: for example,
    localtime_rz (unlike localtime_r) is trivially thread-safe without
    locking.  (Thanks to Christos Zoulas for proposing NetBSD-inspired
    functions, and to Alan Barrett and Jonathan Lennox for helping to
    debug the change.)

    zdump now builds with the tz library unless USE_LTZ is defined to 0,
    This lets zdump use tz features even if the system library lacks them.
    To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
    TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.

    zdump now uses localtime_rz if available, as it's significantly faster,
    and it can help zdump better diagnose invalid time zone names.
    Define HAVE_LOCALTIME_RZ to 0 to suppress this.  HAVE_LOCALTIME_RZ
    defaults to 1 if NETBSD_INSPIRED && USE_LTZ.  When localtime_rz is
    not available, zdump now uses localtime_r and tzset if available,
    as this is a bit cleaner and faster than plain localtime.  Compile
    with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
    lacks these two functions.

    If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
    Although not needed for tz's own applications, which are single-threaded,
    this supports POSIX better if the tz library is used in multithreaded apps.

    Some crashes have been fixed when zdump or the tz library is given
    invalid or outlandish input.

    The tz library no longer mishandles leap seconds on platforms with
    unsigned time_t in time zones that lack ordinary transitions after 1970.

    The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
    already defined, to make it easier to configure on common platforms.
    Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.

    Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
    assumes that reading uninitialized memory yields garbage values
    but does not cause other problems such as traps.

    If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
    more likely to guess right for ambiguous time stamps near
    transitions where tm_isdst does not change.

    If HAVE_STRFTIME_L is defined to 1, the tz library now defines
    strftime_l for compatibility with recent versions of POSIX.
    Only the C locale is supported, though.  HAVE_STRFTIME_L defaults
    to 1 on recent POSIX versions, and to 0 otherwise.

    tzselect -c now uses a hybrid distance measure that works better
    in Africa.  (Thanks to Alan Barrett for noting the problem.)

    The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
    or when time_tz is defined.

    When HAVE_UTMPX_H is set the 'date' command now builds on systems
    whose <utmpx.h> file does not define WTMPX_FILE, and when setting
    the date it updates the wtmpx file if _PATH_WTMPX is defined.
    This affects GNU/Linux and similar systems.

    For easier maintenance later, some C code has been simplified,
    some lint has been removed, and the code has been tweaked so that
    plain 'make' is more likely to work.

    The C type 'bool' is now used for boolean values, instead of 'int'.

    The long-obsolete LOCALE_HOME code has been removed.

    The long-obsolete 'gtime' function has been removed.

  Changes affecting build procedure

    'zdump' no longer links in ialloc.o, as it's not needed.

    'make check_time_t_alternatives' no longer assumes GNU diff.

  Changes affecting distribution tarballs

    The files checktab.awk and zoneinfo2tdf.pl are now distributed in
    the tzdata tarball instead of the tzcode tarball, since they help
    maintain the data.  The NEWS and Theory files are now also
    distributed in the tzdata tarball, as they're relevant for data.
    (Thanks to Alan Barrett for pointing this out.)  Also, the
    leapseconds.awk file is no longer distributed in the tzcode
    tarball, since it belongs in the tzdata tarball (where 2014f
    inadvertently also distributed it).

  Changes affecting documentation and commentary

    A new file CONTRIBUTING is distributed.  (Thanks to Tim Parenti for
    suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
    for debugging it.)

    The man pages have been updated to use function prototypes,
    to document thread-safe variants like localtime_r, and to document
    the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
    mktime_z.

    The fields in Link lines have been renamed to be more descriptive
    and more like the parameters of 'ln'.  LINK-FROM has become TARGET,
    and LINK-TO has become LINK-NAME.

    tz-link.htm mentions the IETF's tzdist working group; Windows
    Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.

    Some broken URLs have been fixed in the commentary.  (Thanks to
    Lester Caine.)

    Commentary about Philippines DST has been updated, and commentary
    on pre-1970 time in India has been added.


Release 2014f - 2014-08-05 17:42:36 -0700

  Changes affecting future time stamps

    Russia will subtract an hour from most of its time zones on 2014-10-26
    at 02:00 local time.  (Thanks to Alexander Krivenyshev.)
    There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
    Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
    (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
    (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
    (Europe/Samara) are not changing their clocks.  The changed zones are
    Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
    Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
    Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
    Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
    subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
    but not its UTC offset.  Two zones are added: Asia/Chita (split
    from Asia/Yakutsk, and also with two hours subtracted) and
    Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
    subtracted).  (Thanks to Tim Parenti for much of the above.)

  Changes affecting time zone abbreviations

    Australian eastern time zone abbreviations are now AEST/AEDT not EST,
    and similarly for the other Australian zones.  That is, for eastern
    standard and daylight saving time the abbreviations are AEST and AEDT
    instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
    and AWST/AWDT are now used instead of the former CST, CWST, and WST.
    This change does not affect UTC offsets, only time zone abbreviations.
    (Thanks to Rich Tibbett and many others.)

    Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UTC+7)
    effective 2014-10-26 at 02:00 local time.

    The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
    has been changed from URUT to XJT.  (Thanks to Luther Ma.)

    Prefer MSK/MSD for Moscow time in Russia, even in other cities.
    Similarly, prefer EET/EEST for eastern European time in Russia.

    Change time zone abbreviations in (western) Samoa to use "ST" and
    "DT" suffixes, as this is more likely to match common practice.
    Prefix "W" to (western) Samoa time when its standard-time offset
    disagrees with that of American Samoa.

    America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.

    Time zone abbreviations have been updated for Japan's two time
    zones used 1896-1937.  JWST now stands for Western Standard
    Time, and JCST for Central Standard Time (formerly this was CJT).
    These abbreviations are now used for time in Korea, Taiwan,
    and Sakhalin while controlled by Japan.

  Changes affecting past time stamps

    China's five zones have been simplified to two, since the post-1970
    differences in the other three seem to have been imaginary.  The
    zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
    removed; backwards-compatibility links still work, albeit with
    different behaviors for time stamps before May 1980.  Asia/Urumqi's
    1980 transition to UTC+8 has been removed, so that it is now at
    UTC+6 and not UTC+8.  (Thanks to Luther Ma and to Alois Treindl;
    Treindl sent helpful translations of two papers by Guo Qingsheng.)

    Some zones have been turned into links, when they differed from existing
    zones only for older UTC offsets where data entries were likely invented.
    These changes affect UTC offsets in pre-1970 time stamps only.  This is
    similar to the change in release 2013e, except this time for western
    Africa.  The affected zones are: Africa/Bamako, Africa/Banjul,
    Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
    Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
    Atlantic/St_Helena.  This also affects the backwards-compatibility
    link Africa/Timbuktu.  (Thanks to Alan Barrett, Stephen Colebourne,
    Tim Parenti, and David Patte for reporting problems in earlier
    versions of this change.)

    Asia/Shanghai's pre-standard-time UT offset has been changed from
    8:05:57 to 8:05:43, the location of Xujiahui Observatory.  Its
    transition to standard time has been changed from 1928 to 1901.

    Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
    then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
    In 1946 it observed DST from 05-15 through 09-30; in 1947
    from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
    (Thanks to Yu-Cheng Chuang.)

    Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.

    Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
    10-03 at 00:00.  (Thanks to Konstantin Hyppönen.)

    Pacific/Pago_Pago has been changed from UTC-11:30 to UTC-11 for the period
    from 1911 to 1950.

    Pacific/Chatham has been changed to New Zealand standard time plus
    45 minutes for the period before 1957, reflecting a 1956 remark in
    the New Zealand parliament.

    Europe/Budapest has several pre-1946 corrections: in 1918 the transition
    out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
    1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
    not 04-06 at 02:00; and there was no DST in 1920.

    Africa/Accra is now assumed to have observed DST from 1920 through 1935.

    Time in Russia before 1927 or so has been corrected by a few seconds in
    the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
    Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
    Europe/Riga.  Also, Moscow's location has been changed to its Kilometer 0
    point.  (Thanks to Vladimir Karpinsky for the Moscow changes.)

  Changes affecting data format

    A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
    The new file's extended format allows multiple country codes per zone.
    The older file is still installed but is deprecated; its format is
    not changing and it will still be distributed for a while, but new
    applications should use the new file.

    The new file format simplifies maintenance of obscure locations.
    To test this, it adds coverage for the Crozet Islands and the
    Scattered Islands.  (Thanks to Tobias Conradi and Antoine Leca.)

    The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
    It is still ASCII now, but commentary about the switch has been added.
    The new file 'zone1970.tab' already uses UTF-8.

  Changes affecting code

    'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
    is defined.  (Thanks to Elliott Hughes for reporting the problem.)

    'zic' no longer mishandles input when ignoring case in locales that
    are not compatible with English, e.g., unibyte Turkish locales when
    compiled with HAVE_GETTEXT.

    Error diagnostics of 'zic' and 'yearistype' have been reworded so that
    they no longer use ASCII '-' as if it were a dash.

    'zic' now rejects output file names that contain '.' or '..' components.
    (Thanks to Tim Parenti for reporting the problem.)

    'zic -v' now warns about output file names that do not follow
    POSIX rules, or that contain a digit or '.'.  (Thanks to Arthur
    David Olson for starting the ball rolling on this.)

    Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.

  Changes affecting build procedure

    'zic' no longer links in localtime.o and asctime.o, as they're not needed.
    (Thanks to John Cochran.)

  Changes affecting documentation and commentary

    The 'Theory' file documents legacy names, the longstanding
    exceptions to the POSIX-inspired file name rules.

    The 'zic' documentation clarifies the role of time types when
    interpreting dates.  (Thanks to Arthur David Olson.)

    Documentation and commentary now prefer UTF-8 to US-ASCII,
    allowing the use of proper accents in foreign words and names.
    Code and data have not changed because of this.  (Thanks to
    Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
    this.)

    Non-HTML documentation and commentary now use plain-text URLs instead of
    HTML insertions, and are more consistent about bracketing URLs when they
    are not already surrounded by white space.  (Thanks to suggestions by
    Steffen Nurpmeso.)

    There is new commentary about Xujiahui Observatory, the five time-zone
    project in China from 1918 to 1949, timekeeping in Japanese-occupied
    Shanghai, and Tibet Time in the 1950s.  The sharp-eyed can spot the
    warlord Jin Shuren in the data.

    Commentary about the coverage of each Russian zone has been standardized.
    (Thanks to Tim Parenti).

    There is new commentary about contemporary timekeeping in Ethiopia.

    Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.

    There is new commentary about time in Poland in 1919.

    Proper credit has been given to DST inventor George Vernon Hudson.

    Commentary about time in Metlakatla, AK and Resolute, NU has been
    improved, with a new source for the former.

    In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
    is uninhabited.

    Commentary about permanent Antarctic bases has been updated.

    Several typos have been corrected.  (Thanks to Tim Parenti for
    contributing some of these fixes.)

    tz-link.htm now mentions the JavaScript libraries Moment Timezone,
    TimezoneJS.Date, Walltime-js, and Timezone.  (Thanks to a heads-up
    from Matt Johnson.)  Also, it mentions the Go 'latlong' package.
    (Thanks to a heads-up from Dirkjan Ochtman.)

    The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
    have been removed.  These obsolescent US Naval Observatory entries were no
    longer helpful for maintenance.  (Thanks to Tim Parenti for the suggestion.)


Release 2014e - 2014-06-12 21:53:52 -0700

  Changes affecting near-future time stamps

    Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
    (Thanks to Imed Chihi.)  Guess that from 2015 on Egypt will temporarily
    switch to standard time at 24:00 the last Thursday before Ramadan, and
    back to DST at 00:00 the first Friday after Ramadan.

    Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00.  (Thanks
    to Milamber Space Network.)  Guess that from 2015 on Morocco will
    temporarily switch to standard time at 03:00 the last Saturday before
    Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.

  Changes affecting past time stamps

    The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
    "MSD" for Moscow's double daylight time in summer 1921.  Also, a typo
    "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
    in 1991.  (Thanks to Hank W. for reporting the problems.)

  Changes affecting commentary

    tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
    draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
    removes stale pointers to World Time Explorer and WORLDTIME.


Release 2014d - 2014-05-27 21:34:40 -0700

  Changes affecting code

    zic no longer generates files containing time stamps before the Big Bang.
    This works around GNOME bug 730332
    <https://bugzilla.gnome.org/show_bug.cgi?id=730332>.
    (Thanks to Leonardo Chiquitto for reporting the bug, and to
    Arthur David Olson and James Cloos for suggesting improvements to the fix.)

  Changes affecting documentation

    tz-link.htm now mentions GNOME.


Release 2014c - 2014-05-13 07:44:13 -0700

  Changes affecting near-future time stamps

    Egypt observes DST starting 2014-05-15 at 24:00.
    (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
    Details have not been announced, except that DST will not be observed
    during Ramadan.  Guess that DST will stop during the same Ramadan dates as
    Morocco, and that Egypt's future spring and fall transitions will be the
    same as 2010 when it last observed DST, namely April's last Friday at
    00:00 to September's last Thursday at 23:00 standard time.  Also, guess
    that Ramadan transitions will be at 00:00 standard time.

  Changes affecting code

    zic now generates transitions for minimum time values, eliminating guesswork
    when handling low-valued time stamps.  (Thanks to Arthur David Olson.)

    Port to Cygwin sans glibc.  (Thanks to Arthur David Olson.)

  Changes affecting commentary and documentation

    Remove now-confusing comment about Jordan.  (Thanks to Oleksii Nochovnyi.)


Release 2014b - 2014-03-24 21:28:50 -0700

  Changes affecting near-future time stamps

    Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
    (Thanks to Alexander Krivenyshev.)  Move its zone.tab entry from UA to RU.

    New entry for Troll station, Antarctica.  (Thanks to Paul-Inge Flakstad and
    Bengt-Inge Larsson.)  This is currently an approximation; a better version
    will require the zic and localtime fixes mentioned below, and the plan is
    to wait for a while until at least the zic fixes propagate.

  Changes affecting code

    'zic' and 'localtime' no longer reject locations needing four transitions
    per year for the foreseeable future.  (Thanks to Andrew Main (Zefram).)
    Also, 'zic' avoids some unlikely failures due to integer overflow.

  Changes affecting build procedure

    'make check' now detects Rule lines defined but never used.
    The NZAQ rules, an instance of this problem, have been removed.

  Changes affecting commentary and documentation

    Fix Tuesday/Thursday typo in description of time in Israel.
    (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)

    Microsoft Windows 8.1 doesn't support tz database names.  (Thanks
    to Donald MacQueen.)  Instead, the Microsoft Windows Store app
    library supports them.

    Add comments about Johnston Island time in the 1960s.
    (Thanks to Lyle McElhaney.)

    Morocco's 2014 DST start will be as predicted.
    (Thanks to Sebastien Willemijns.)


Release 2014a - 2014-03-07 23:30:29 -0800

  Changes affecting near-future time stamps

    Turkey begins DST on 2014-03-31, not 03-30.  (Thanks to Faruk Pasin for
    the heads-up, and to Tim Parenti for simplifying the update.)

  Changes affecting past time stamps

    Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
    (Thanks to Steffen Thorsen.)

    Ukraine switched from Moscow to Eastern European time on 1990-07-01
    (not 1992-01-01), and observed DST during the entire next winter.
    (Thanks to Vladimir in Moscow via Alois Treindl.)

    In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
    (Thanks to Avigdor Finkelstein.)

  Changes affecting code

    A uninitialized-storage bug in 'localtime' has been fixed.
    (Thanks to Logan Chien.)

  Changes affecting the build procedure

    The settings for 'make check_web' now default to Ubuntu 13.10.

  Changes affecting commentary and documentation

    The boundary of the US Pacific time zone is given more accurately.
    (Thanks to Alan Mintz.)

    Chile's 2014 DST will be as predicted.  (Thanks to José Miguel Garrido.)

    Paraguay's 2014 DST will be as predicted.  (Thanks to Carlos Raúl Perasso.)

    Better descriptions of countries with same time zone history as
    Trinidad and Tobago since 1970.  (Thanks to Alan Barrett for suggestion.)

    Several changes affect tz-link.htm, the main web page.

      Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
      David Braverman).

      Mention xCal (Internet RFC 6321) and jCal.

      Microsoft has some support for tz database names.

      CLDR data formats include both XML and JSON.

      Mention Maggiolo's map of solar vs standard time.
      (Thanks to Arthur David Olson.)

      Mention TZ4Net.  (Thanks to Matt Johnson.)

      Mention the timezone-olson Haskell package.

      Mention zeitverschiebung.net.  (Thanks to Martin Jäger.)

      Remove moribund links to daylight-savings-time.info and to
      Simple Timer + Clocks.

      Update two links.  (Thanks to Oscar van Vlijmen.)

      Fix some formatting glitches, e.g., remove random newlines from
      abbr elements' title attributes.


Release 2013i - 2013-12-17 07:25:23 -0800

  Changes affecting near-future time stamps:

    Jordan switches back to standard time at 00:00 on December 20, 2013.
    The 2006-2011 transition schedule is planned to resume in 2014.
    (Thanks to Steffen Thorsen.)

  Changes affecting past time stamps:

    In 2004, Cuba began DST on March 28, not April 4.
    (Thanks to Steffen Thorsen.)

  Changes affecting code

    The compile-time flag NOSOLAR has been removed, as nowadays the
    benefit of slightly shrinking runtime table size is outweighed by the
    cost of disallowing potential future updates that exceed old limits.

  Changes affecting documentation and commentary

    The files solar87, solar88, and solar89 are no longer distributed.
    They were a negative experiment - that is, a demonstration that
    tz data can represent solar time only with some difficulty and error.
    Their presence in the distribution caused confusion, as Riyadh
    civil time was generally not solar time in those years.

    tz-link.htm now mentions Noda Time.  (Thanks to Matt Johnson.)


Release 2013h - 2013-10-25 15:32:32 -0700

  Changes affecting current and future time stamps:

    Libya has switched its time zone back to UTC+2 without DST,
    instead of UTC+1 with DST.  (Thanks to Even Scharning.)

    Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
    (Thanks to Gwillim Law.)

  Changes affecting future time stamps:

    Acre and (we guess) western Amazonas will switch from UTC-4 to UTC-5
    on 2013-11-10.  This affects America/Rio_Branco and America/Eirunepe.
    (Thanks to Steffen Thorsen.)

    Add entries for DST transitions in Morocco in the year 2038.
    This avoids some year-2038 glitches introduced in 2013g.
    (Thanks to Yoshito Umaoka for reporting the problem.)

  Changes affecting API

    The 'tzselect' command no longer requires the 'select' command,
    and should now work with /bin/sh on more platforms.  It also works
    around a bug in BusyBox awk before version 1.21.0.  (Thanks to
    Patrick 'P. J.' McDermott and Alan Barrett.)

  Changes affecting code

    Fix localtime overflow bugs with 32-bit unsigned time_t.

    zdump no longer assumes sscanf returns maximal values on overflow.

  Changes affecting the build procedure

    The builder can specify which programs to use, if any, instead of
    'ar' and 'ranlib', and libtz.a is now built locally before being
    installed.  (Thanks to Michael Forney.)

    A dependency typo in the 'zdump' rule has been fixed.
    (Thanks to Andrew Paprocki.)

    The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
    work as specified by POSIX.2-1992 or later; this is portable nowadays.

    'make clean' no longer removes 'leapseconds', since it's
    host-independent and is part of the distribution.

    The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.

  Changes affecting documentation and commentary

    tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
    (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).

    Update URLs in tz-link page.  Add URLs for Microsoft Windows, since
    8.1 introduces tz support.  Remove URLs for Tru64 and UnixWare (no
    longer maintained) and for old advisories.  SOFA now does C.

Release 2013g - 2013-09-30 21:08:26 -0700

  Changes affecting current and near-future time stamps

    Morocco now observes DST from the last Sunday in March to the last
    Sunday in October, not April to September respectively.  (Thanks
    to Steffen Thorsen.)

  Changes affecting 'zic'

    'zic' now runs on platforms that lack both hard links and symlinks.
    (Thanks to Theo Veenker for reporting the problem, for MinGW.)
    Also, fix some bugs on platforms that lack hard links but have symlinks.

    'zic -v' again warns that Asia/Tehran has no POSIX environment variable
    to predict the far future, fixing a bug introduced in 2013e.

  Changes affecting the build procedure

    The 'leapseconds' file is again put into the tzdata tarball.
    Also, 'leapseconds.awk', so tzdata is self-contained.  (Thanks to
    Matt Burgess and Ian Abbott.)  The timestamps of these and other
    dependent files in tarballs are adjusted more consistently.

  Changes affecting documentation and commentary

    The README file is now part of the data tarball as well as the code.
    It now states that files are public domain unless otherwise specified.
    (Thanks to Andrew Main (Zefram) for asking for clarifications.)
    Its details about the 1989 release moved to a place of honor near
    the end of NEWS.


Release 2013f - 2013-09-24 23:37:36 -0700

  Changes affecting near-future time stamps

    Tocantins will very likely not observe DST starting this spring.
    (Thanks to Steffen Thorsen.)

    Jordan will likely stay at UTC+3 indefinitely, and will not fall
    back this fall.

    Palestine will fall back at 00:00, not 01:00.  (Thanks to Steffen Thorsen.)

  Changes affecting API

    The types of the global variables 'timezone' and 'altzone' (if present)
    have been changed back to 'long'.  This is required for 'timezone'
    by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
    These variables were originally 'long' in the tz code, but were
    mistakenly changed to 'time_t' in 1987; nobody reported the
    incompatibility until now.  The difference matters on x32, where
    'long' is 32 bits and 'time_t' is 64.  (Thanks to Elliott Hughes.)

  Changes affecting the build procedure

    Avoid long strings in leapseconds.awk to work around a mawk bug.
    (Thanks to Cyril Baurand.)

  Changes affecting documentation and commentary

    New file 'NEWS' that contains release notes like this one.

    Paraguay's law does not specify DST transition time; 00:00 is customary.
    (Thanks to Waldemar Villamayor-Venialbo.)

    Minor capitalization fixes.

  Changes affecting version-control only

    The experimental GitHub repository now contains annotated and
    signed tags for recent releases, e.g., '2013e' for Release 2013e.
    Releases are tagged starting with 2012e; earlier releases were
    done differently, and tags would either not have a simple name or
    not exactly match what was released.

    'make set-timestamps' is now simpler and a bit more portable.


Release 2013e - 2013-09-19 23:50:04 -0700

  Changes affecting near-future time stamps

    This year Fiji will start DST on October 27, not October 20.
    (Thanks to David Wheeler for the heads-up.)  For now, guess that
    Fiji will continue to spring forward the Sunday before the fourth
    Monday in October.

  Changes affecting current and future time zone abbreviations

    Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
    time zone abbreviations since 1932.  (Thanks to George Ziegler,
    Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
    Benny Lin.)  This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
    Asia/Makassar, and Asia/Pontianak.

    Use ART (UTC-3, standard time), rather than WARST (also UTC-3, but
    daylight saving time) for San Luis, Argentina since 2009.

  Changes affecting Godthåb time stamps after 2037 if version mismatch

    Allow POSIX-like TZ strings where the transition time's hour can
    range from -167 through 167, instead of the POSIX-required 0
    through 24.  E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
    new Fiji rules.  This is a more-compact way to represent
    far-future time stamps for America/Godthab, America/Santiago,
    Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
    Pacific/Easter, and Pacific/Fiji.  Other zones are unaffected by
    this change.  (Derived from a suggestion by Arthur David Olson.)

    Allow POSIX-like TZ strings where daylight saving time is in
    effect all year.  E.g., TZ='WART4WARST,J1/0,J365/25' for Western
    Argentina Summer Time all year.  This supports a more-compact way
    to represent the 2013d data for America/Argentina/San_Luis.
    Because of the change for San Luis noted above this change does not
    affect the current data.  (Thanks to Andrew Main (Zefram) for
    suggestions that improved this change.)

    Where these two TZ changes take effect, there is a minor extension
    to the tz file format in that it allows new values for the
    embedded TZ-format string, and the tz file format version number
    has therefore been increased from 2 to 3 as a precaution.
    Version-2-based client code should continue to work as before for
    all time stamps before 2038.  Existing version-2-based client code
    (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
    files, and typically works in practice even for time stamps after
    2037; the only known exception is America/Godthab.

  Changes affecting time stamps before 1970

    Pacific/Johnston is now a link to Pacific/Honolulu.  This corrects
    some errors before 1947.

    Some zones have been turned into links, when they differ from existing
    zones only in older data entries that were likely invented or that
    differ only in LMT or transitions from LMT.  These changes affect
    only time stamps before 1943.  The affected zones are:
    Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
    America/Grenada, America/Guadeloupe, America/Marigot,
    America/Montserrat, America/St_Barthelemy, America/St_Kitts,
    America/St_Lucia, America/St_Thomas, America/St_Vincent,
    America/Tortola, and Europe/Vaduz.  (Thanks to Alois Treindl for
    confirming that the old Europe/Vaduz zone was wrong and the new
    link is better for WWII-era times.)

    Change Kingston Mean Time from -5:07:12 to -5:07:11.  This affects
    America/Cayman, America/Jamaica and America/Grand_Turk time stamps
    from 1890 to 1912.

    Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
    This affects Europe/Zurich time stamps from 1853 to 1894.  (Thanks
    to Alois Treindl).

    Change the date of the circa-1850 Zurich transition from 1849-09-12
    to 1853-07-16, overriding Shanks with data from Messerli about
    postal and telegraph time in Switzerland.

  Changes affecting time zone abbreviations before 1970

    For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
    as Jakarta was called Batavia back then.

  Changes affecting API

    The 'zic' command now outputs a dummy transition when far-future
    data can't be summarized using a TZ string, and uses a 402-year
    window rather than a 400-year window.  For the current data, this
    affects only the Asia/Tehran file.  It does not affect any of the
    time stamps that this file represents, so zdump outputs the same
    information as before.  (Thanks to Andrew Main (Zefram).)

    The 'date' command has a new '-r' option, which lets you specify
    the integer time to display, a la FreeBSD.

    The 'tzselect' command has two new options '-c' and '-n', which lets you
    select a zone based on latitude and longitude.

    The 'zic' command's '-v' option now warns about constructs that
    require the new version-3 binary file format.  (Thanks to Arthur
    David Olson for the suggestion.)

    Support for floating-point time_t has been removed.
    It was always dicey, and POSIX no longer requires it.
    (Thanks to Eric Blake for suggesting to the POSIX committee to
    remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
    Heninger, Arthur David Olson, and Alois Treindl, for reporting
    bugs and elucidating some of the corners of the old floating-point
    implementation.)

    The signatures of 'offtime', 'timeoff', and 'gtime' have been
    changed back to the old practice of using 'long' to represent UT
    offsets.  This had been inadvertently and mistakenly changed to
    'int_fast32_t'.  (Thanks to Christos Zoulas.)

    The code avoids undefined behavior on integer overflow in some
    more places, including gmtime, localtime, mktime and zdump.

  Changes affecting the zdump utility

    zdump now outputs "UT" when referring to Universal Time, not "UTC".
    "UTC" does not make sense for time stamps that predate the introduction
    of UTC, whereas "UT", a more-generic term, does.  (Thanks to Steve Allen
    for clarifying UT vs UTC.)

  Data changes affecting behavior of tzselect and similar programs

    Country code BQ is now called the more-common name "Caribbean Netherlands"
    rather than the more-official "Bonaire, St Eustatius & Saba".

    Remove from zone.tab the names America/Montreal, America/Shiprock,
    and Antarctica/South_Pole, as they are equivalent to existing
    same-country-code zones for post-1970 time stamps.  The data entries for
    these names are unchanged, so the names continue to work as before.

  Changes affecting code internals

    zic -c now runs way faster on 64-bit hosts when given large numbers.

    zic now uses vfprintf to avoid allocating and freeing some memory.

    tzselect now computes the list of continents from the data,
    rather than have it hard-coded.

    Minor changes pacify GCC 4.7.3 and GCC 4.8.1.

  Changes affecting the build procedure

    The 'leapseconds' file is now generated automatically from a
    new file 'leap-seconds.list', which is a copy of
    <ftp://time.nist.gov/pub/leap-seconds.list>.
    A new source file 'leapseconds.awk' implements this.
    The goal is simplification of the future maintenance of 'leapseconds'.

    When building the 'posix' or 'right' subdirectories, if the
    subdirectory would be a copy of the default subdirectory, it is
    now made a symbolic link if that is supported.  This saves about
    2 MB of file system space.

    The links America/Shiprock and Antarctica/South_Pole have been
    moved to the 'backward' file.  This affects only nondefault builds
    that omit 'backward'.

  Changes affecting version-control only

    .gitignore now ignores 'date'.

  Changes affecting documentation and commentary

    Changes to the 'tzfile' man page

      It now mentions that the binary file format may be extended in
      future versions by appending data.

      It now refers to the 'zdump' and 'zic' man pages.

    Changes to the 'zic' man page

      It lists conditions that elicit a warning with '-v'.

      It says that the behavior is unspecified when duplicate names
      are given, or if the source of one link is the target of another.

      Its examples are updated to match the latest data.

      The definition of white space has been clarified slightly.
      (Thanks to Michael Deckers.)

    Changes to the 'Theory' file

      There is a new section about the accuracy of the tz database,
      describing the many ways that errors can creep in, and
      explaining why so many of the pre-1970 time stamps are wrong or
      misleading (thanks to Steve Allen, Lester Caine, and Garrett
      Wollman for discussions that contributed to this).

      The 'Theory' file describes LMT better (this follows a
      suggestion by Guy Harris).

      It refers to the 2013 edition of POSIX rather than the 2004 edition.

      It's mentioned that excluding 'backward' should not affect the
      other data, and it suggests at least one zone.tab name per
      inhabited country (thanks to Stephen Colebourne).

      Some longstanding restrictions on names are documented, e.g.,
      'America/New_York' precludes 'America/New_York/Bronx'.

      It gives more reasons for the 1970 cutoff.

      It now mentions which time_t variants are supported, such as
      signed integer time_t.  (Thanks to Paul Goyette for reporting
      typos in an experimental version of this change.)

      (Thanks to Philip Newton for correcting typos in these changes.)

    Documentation and commentary is more careful to distinguish UT in
    general from UTC in particular.  (Thanks to Steve Allen.)

    Add a better source for the Zurich 1894 transition.
    (Thanks to Pierre-Yves Berger.)

    Update shapefile citations in tz-link.htm.  (Thanks to Guy Harris.)


Release 2013d - 2013-07-05 07:38:01 -0700

  Changes affecting future time stamps:

    Morocco's midsummer transitions this year are July 7 and August 10,
    not July 9 and August 8.  (Thanks to Andrew Paprocki.)

    Israel now falls back on the last Sunday of October.
    (Thanks to Ephraim Silverberg.)

  Changes affecting past time stamps:

    Specify Jerusalem's location more precisely; this changes the pre-1880
    times by 2 s.

  Changing affecting metadata only:

    Fix typos in the entries for country codes BQ and SX.

  Changes affecting code:

    Rework the code to fix a bug with handling Australia/Macquarie on
    32-bit hosts (thanks to Arthur David Olson).

    Port to platforms like NetBSD, where time_t can be wider than long.

    Add support for testing time_t types other than the system's.
    Run 'make check_time_t_alternatives' to try this out.
    Currently, the tests fail for unsigned time_t;
    this should get fixed at some point.

  Changes affecting documentation and commentary:

    Deemphasize the significance of national borders.

    Update the zdump man page.

    Remove obsolete NOID comment (thanks to Denis Excoffier).

    Update several URLs and comments in the web pages.

    Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).

    Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).


Release 2013c - 2013-04-19 16:17:40 -0700

  Changes affecting current and future time stamps:

    Palestine observed DST starting March 29, 2013.  (Thanks to
    Steffen Thorsen.)  From 2013 on, Gaza and Hebron both observe DST,
    with the predicted rules being the last Thursday in March at 24:00
    to the first Friday on or after September 21 at 01:00.

    Assume that the recent change to Paraguay's DST rules is permanent,
    by moving the end of DST to the 4th Sunday in March every year.
    (Thanks to Carlos Raúl Perasso.)

  Changes affecting past time stamps:

    Fix some historical data for Palestine to agree with that of
    timeanddate.com, as follows:

	  The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
	  00:00 Apr 1.

	  The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
	  02:00.

	  The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.

	  The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.

	  The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.

	  The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.

    Fix times of habitation for Macquarie to agree with the Tasmania
    Parks & Wildlife Service history, which indicates that permanent
    habitation was 1899-1919 and 1948 on.

  Changing affecting metadata only:

    Macquarie Island is politically part of Australia, not Antarctica.
    (Thanks to Tobias Conradi.)

    Sort Macquarie more-consistently with other parts of Australia.
    (Thanks to Tim Parenti.)


Release 2013b - 2013-03-10 22:33:40 -0700

  Changes affecting current and future time stamps:

    Haiti uses US daylight-saving rules this year, and presumably future years.
    This changes time stamps starting today.  (Thanks to Steffen Thorsen.)

    Paraguay will end DST on March 24 this year.
    (Thanks to Steffen Thorsen.)  For now, assume it's just this year.

    Morocco does not observe DST during Ramadan;
    try to predict Ramadan in Morocco as best we can.
    (Thanks to Erik Homoet for the heads-up.)

  Changes affecting commentary:

    Update URLs in tz-link page.  Add URLs for webOS, BB10, iOS.
    Update URL for Solaris.  Mention Internet RFC 6557.
    Update Internet RFCs 2445->5545, 2822->5322.
    Switch from FTP to HTTP for Internet RFCs.


Release 2013a - 2013-02-27 09:20:35 -0800

  Change affecting binary data format:

    The zone offset at the end of version-2-format zone files is now
    allowed to be 24:00, as per POSIX.1-2008.  (Thanks to Arthur David Olson.)

  Changes affecting current and future time stamps:

    Chile's 2013 rules, and we guess rules for 2014 and later, will be
    the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
    (Thanks to Steffen Thorsen and Robert Elz.)

    New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
    (Thanks to Tobias Conradi and Arthur David Olson.)

  Many changes affect historical time stamps before 1940.
  These were deduced from: Milne J. Civil time. Geogr J. 1899
  Feb;13(2):173-94 <http://www.jstor.org/stable/1774359>.

  Changes affecting the code:

    Fix zic bug that mishandled Egypt's 2010 changes (this also affected
    the data).  (Thanks to Arthur David Olson.)

    Fix localtime bug when time_t is unsigned and data files were generated
    by a signed time_t system.  (Thanks to Doug Bailey for reporting and
    to Arthur David Olson for fixing.)

    Allow the email address for bug reports to be set by the packager.
    The default is tz@iana.org, as before.  (Thanks to Joseph S. Myers.)

    Update HTML checking to be compatible with Ubuntu 12.10.

    Check that files are a safe subset of ASCII.  At some point we may
    relax this requirement to a safe subset of UTF-8.  Without the
    check, some non-UTF-8 encodings were leaking into the distribution.

  Commentary changes:

    Restore a comment about copyright notices that was inadvertently deleted.
    (Thanks to Arthur David Olson.)

    Improve the commentary about which districts observe what times
    in Russia.  (Thanks to Oscar van Vlijmen and Arthur David Olson).

    Add web page links to tz.js.

    Add "Run by the Monkeys" to tz-art.  (Thanks to Arthur David Olson.)


Release 2012j - 2012-11-12 18:34:49 -0800

  Libya moved to CET this weekend, but with DST planned next year.
  (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)

  Signatures now have the extension .asc, not .sign, as that's more
  standard.  (Thanks to Phil Pennock.)

  The output of 'zdump --version', and of 'zic --version', now
  uses a format that is more typical for --version.
  (Thanks to Joseph S. Myers.)

  The output of 'tzselect --help', 'zdump --help', and 'zic --help'
  now uses tz@iana.org rather than the old elsie address.

  zic -v now complains about abbreviations that are less than 3
  or more than 6 characters, as per Posix.  Formerly, it checked
  for abbreviations that were more than 3.

  'make public' no longer puts its temporary directory under /tmp,
  and uses the just-built zic rather than the system zic.

  Various fixes to documentation and commentary.


Release 2012i - 2012-11-03 12:57:09 -0700

  Cuba switches from DST tomorrow at 01:00.  (Thanks to Steffen Thorsen.)

  Linker flags can now be specified via LDFLAGS.
  AWK now defaults to 'awk', not 'nawk'.
  The shell in tzselect now defaults to /bin/bash, but this can
  be overridden by specifying KSHELL.
  The main web page now mentions the unofficial GitHub repository.
  (Thanks to Mike Frysinger.)

  Tarball signatures can now be built by running 'make signatures'.
  There are also new makefile rules 'tarballs', 'check_public', and
  separate makefile rules for each tarball and signature file.
  A few makefile rules are now more portable to strict POSIX.

  The main web page now lists the canonical IANA URL.


Release 2012h - 2012-10-26 22:49:10 -0700

  Bahia no longer has DST.  (Thanks to Kelley Cook.)

  Tocantins has DST.  (Thanks to Rodrigo Severo.)

  Israel has new DST rules next year.  (Thanks to Ephraim Silverberg.)

  Jordan stays on DST this winter.  (Thanks to Steffen Thorsen.)

  Web page updates.

  More C modernization, except that at Arthur David Olson's suggestion
  the instances of 'register' were kept.


Release 2012g - 2012-10-17 20:59:45 -0700

  Samoa fall 2012 and later.  (Thanks to Nicholas Pereira and Robert Elz.)

  Palestine fall 2012.  (Thanks to Steffen Thorsen.)

  Assume C89.

  To attack the version-number problem, this release ships the file
  'Makefile' (which contains the release number) in both the tzcode and
  the tzdata tarballs.  The two Makefiles are identical, and should be
  identical in any matching pair of tarballs, so it shouldn't matter
  which order you extract the tarballs.  Perhaps we can come up with a
  better version-number scheme at some point; this scheme does have the
  virtue of not adding more files.


Release 2012f - 2012-09-12 23:17:03 -0700

  * australasia (Pacific/Fiji): Fiji DST is October 21 through January
    20 this year.  (Thanks to Steffen Thorsen.)


Release 2012e - 2012-08-02 20:44:55 -0700

  * australasia (Pacific/Fakaofo): Tokelau is UTC+13, not UTC+14.
    (Thanks to Steffen Thorsen.)

  * Use a single version number for both code and data.

  * .gitignore: New file.

  * Remove trailing white space.


Release code2012c-data2012d - 2012-07-19 16:35:33 -0700

  Changes for Morocco's time stamps, which take effect in a couple of
  hours, along with infrastructure changes to accommodate how the tz
  code and data are released on IANA.


Release data2012c - 2012-03-27 12:17:25 -0400

  africa
	Summer time changes for Morocco (to start late April 2012)

  asia
	Changes for 2012 for Gaza & the West Bank (Hebron) and Syria

  northamerica
	Haiti following US/Canada rules for 2012 (and we're assuming,
	for now anyway, for the future).


Release 2012b - 2012-03-02 12:29:15 +0700

  There is just one change to tzcode2012b (compared with 2012a):
  the Makefile that was accidentally included with 2012a has been
  replaced with the version that should have been there, which is
  identical with the previous version (from tzcode2011i).

  There are just two changes in tzdata2012b compared with 2012a.

  Most significantly, summer time in Cuba has been delayed 3 weeks
  (now starts April 1 rather than March 11).   Since Mar 11 (the old start
  date, as listed in 2012a) is just a little over a week away, this
  change is urgent.

  Less importantly, an excess tab in one of the changes in zone.tab
  in 2012a has been removed.


Release 2012a - 2012-03-01 18:28:10 +0700

  The changes in tzcode2012a (compared to the previous version, 2011i)
  are entirely to the README and tz-art.htm and tz-link.htm files, if
  none of those concern you, you can ignore the code update.  The changes
  reflect the changed addresses for the mailing list and the code and
  data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
  has been added to tz-link.htm).

  In tzdata2012a (compared to the previous release, which was 2011n)
  the major changes are:
	Chile 2011/2012 and 2012/2013 summer time date adjustments.
	Falkland Islands onto permanent summer time (we're assuming for the
		foreseeable future, though 2012 is all we're fairly certain of.)
	Armenia has abolished Summer Time.
	Tokelau jumped the International Date Line back last December
		(just the same as their near neighbour, Samoa).
	America/Creston is a new zone for a small area of British Columbia
	There will be a leapsecond 2012-06-30 23:59:60 UTC.

  Other minor changes are:
	Corrections to 1918 Canadian summer time end dates.
	Updated URL for UK time zone history (in comments)
	A few typos in Le Corre's list of free French place names (comments)


Release data2011n - 2011-10-30 14:57:54 +0700

  There are three changes of note - most urgently, Cuba (America/Havana)
  has extended summer time by two weeks, now to end on Nov 13, rather than
  the (already past) Oct 30.   Second, the Pridnestrovian Moldavian Republic
  (Europe/Tiraspol) decided not to split from the rest of Moldova after
  all, and consequently that zone has been removed (again) and reinstated
  in the "backward" file as a link to Europe/Chisinau.   And third, the
  end date for Fiji's summer time this summer was moved forward from the
  earlier planned Feb 26, to Jan 22.

  Apart from that, Moldova (MD) returns to a single entry in zone.tab
  (and the incorrect syntax that was in the 2011m version of that file
  is so fixed - it would have been fixed in a different way had this
  change not happened - that's the "missing" sccs version id).


Release data2011m - 2011-10-24 21:42:16 +0700

  In particular, the typos in comments in the data (2011-11-17 should have
  been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
  Tim Parenti noted) have been fixed, and the change for Ukraine has been
  made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
  Tim Parenti, and also Denys Gavrysh)

  In addition, I added Europe/Tiraspol to zone.tab.

  This time, all the files have new version numbers...  (including the files
  otherwise unchanged in 2011m that were changed in 2011l but didn't get new
  version numbers there...)


Release data2011l - 2011-10-10 11:15:43 +0700

  There are just 2 changes that cause different generated tzdata files from
  zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
  is included, but commented out.  Compared with the diff I sent out last week,
  this version also includes attributions for the sources for the changes
  (in much the same format as ado used, but the html tags have not been
  checked, verified, or used in any way at all, so if there are errors there,
  please let me know.)


Release data2011k - 2011-09-20 17:54:03 -0400

  [not summarized]


Release data2011j - 2011-09-12 09:22:49 -0400

  (contemporary changes for Samoa; past changes for Kenya, Uganda, and
  Tanzania); there are also two spelling corrections to comments in
  the australasia file (with thanks to Christos Zoulas).


Release 2011i - 2011-08-29 05:56:32 -0400

  [not summarized]


Release data2011h - 2011-06-15 18:41:48 -0400

  Russia and Curaçao changes


Release 2011g - 2011-04-25 09:07:22 -0400

  update the rules for Egypt to reflect its abandonment of DST this year


Release 2011f - 2011-04-06 17:14:53 -0400

  [not summarized]


Release 2011e - 2011-03-31 16:04:38 -0400

  Morocco, Chile, and tz-link changes


Release 2011d - 2011-03-14 09:18:01 -0400

  changes that impact present-day time stamps in Cuba, Samoa, and Turkey


Release 2011c - 2011-03-07 09:30:09 -0500

  These do affect current time stamps in Chile and Annette Island, Canada.


Release 2011b - 2011-02-07 08:44:50 -0500

  [not summarized]


Release 2011a - 2011-01-24 10:30:16 -0500

  [not summarized]


Release data2010o - 2010-11-01 09:18:23 -0400

  change to the end of DST in Fiji in 2011


Release 2010n - 2010-10-25 08:19:17 -0400

  [not summarized]


Release 2010m - 2010-09-27 09:24:48 -0400

  Hong Kong, Vostok, and zic.c changes


Release 2010l - 2010-08-16 06:57:25 -0400

  [not summarized]


Release 2010k - 2010-07-26 10:42:27 -0400

  [not summarized]


Release 2010j - 2010-05-10 09:07:48 -0400

  changes for Bahía de Banderas and for version naming


Release data2010i - 2010-04-16 18:50:45 -0400

  the end of DST in Morocco on 2010-08-08


Release data2010h - 2010-04-05 09:58:56 -0400

  [not summarized]


Release data2010g - 2010-03-24 11:14:53 -0400

  [not summarized]


Release 2010f - 2010-03-22 09:45:46 -0400

  [not summarized]


Release data2010e - 2010-03-08 14:24:27 -0500

  corrects the Dhaka bug found by Danvin Ruangchan


Release data2010d - 2010-03-06 07:26:01 -0500

  [not summarized]


Release 2010c - 2010-03-01 09:20:58 -0500

  changes including KRE's suggestion for earlier initialization of
  "goahead" and "goback" structure elements


Release code2010a - 2010-02-16 10:40:04 -0500

  [not summarized]


Release data2010b - 2010-01-20 12:37:01 -0500

  Mexico changes


Release data2010a - 2010-01-18 08:30:04 -0500

  changes to Dhaka


Release data2009u - 2009-12-26 08:32:28 -0500

  changes to DST in Bangladesh


Release 2009t - 2009-12-21 13:24:27 -0500

  [not summarized]


Release data2009s - 2009-11-14 10:26:32 -0500

  (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change


Release 2009r - 2009-11-09 10:10:31 -0500

  "antarctica" and "tz-link.htm" changes


Release 2009q - 2009-11-02 09:12:40 -0500

  with two corrections as reported by Eric Muller and Philip Newton


Release data2009p - 2009-10-23 15:05:27 -0400

  Argentina (including San Luis) changes (with the correction from
  Mariano Absatz)


Release data2009o - 2009-10-14 16:49:38 -0400

  Samoa (commentary only), Pakistan, and Bangladesh changes


Release data2009n - 2009-09-22 15:13:38 -0400

  added commentary for Argentina and a change to the end of DST in
  2009 in Pakistan


Release data2009m - 2009-09-03 10:23:43 -0400

  Samoa and Palestine changes


Release data2009l - 2009-08-14 09:13:07 -0400

  Samoa (comments only) and Egypt


Release 2009k - 2009-07-20 09:46:08 -0400

  [not summarized]


Release data2009j - 2009-06-15 06:43:59 -0400

  Bangladesh change (with a short turnaround since the DST change is
  impending)


Release 2009i - 2009-06-08 09:21:22 -0400

  updating for DST in Bangladesh this year


Release 2009h - 2009-05-26 09:19:14 -0400

  [not summarized]


Release data2009g - 2009-04-20 16:34:07 -0400

  Cairo


Release data2009f - 2009-04-10 11:00:52 -0400

  correct DST in Pakistan


Release 2009e - 2009-04-06 09:08:11 -0400

  [not summarized]


Release 2009d - 2009-03-23 09:38:12 -0400

  Morocco, Tunisia, Argentina, and American Astronomical Society changes


Release data2009c - 2009-03-16 09:47:51 -0400

  change to the start of Cuban DST


Release 2009b - 2009-02-09 11:15:22 -0500

  [not summarized]


Release 2009a - 2009-01-21 10:09:39 -0500

  [not summarized]


Release data2008i - 2008-10-21 12:10:25 -0400

  southamerica and zone.tab files, with Argentina DST rule changes and
  United States zone reordering and recommenting


Release 2008h - 2008-10-13 07:33:56 -0400

  [not summarized]


Release 2008g - 2008-10-06 09:03:18 -0400

  Fix a broken HTML anchor and update Brazil's DST transitions;
  there's also a slight reordering of information in tz-art.htm.


Release data2008f - 2008-09-09 22:33:26 -0400

  [not summarized]


Release 2008e - 2008-07-28 14:11:17 -0400

  changes by Arthur David Olson and Jesper Nørgaard Welen


Release data2008d - 2008-07-07 09:51:38 -0400

  changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo


Release data2008c - 2008-05-19 17:48:03 -0400

  Pakistan, Morocco, and Mongolia


Release data2008b - 2008-03-24 08:30:59 -0400

  including renaming Asia/Calcutta to Asia/Kolkata, with a backward
  link provided


Release 2008a - 2008-03-08 05:42:16 -0500

  [not summarized]


Release 2007k - 2007-12-31 10:25:22 -0500

  most importantly, changes to the "southamerica" file based on
  Argentina's readoption of daylight saving time


Release 2007j - 2007-12-03 09:51:01 -0500

  1. eliminate the "P" (parameter) macro;

  2. the "noncontroversial" changes circulated on the time zone
  mailing list (less the changes to "logwtmp.c");

  3. eliminate "too many transition" errors when "min" is used in time
  zone rules;

  4. changes by Paul Eggert (including updated information for Venezuela).


Release data2007i - 2007-10-30 10:28:11 -0400

  changes for Cuba and Syria


Release 2007h - 2007-10-01 10:05:51 -0400

  changes by Paul Eggert, as well as an updated link to the ICU
  project in tz-link.htm


Release 2007g - 2007-08-20 10:47:59 -0400

  changes by Paul Eggert

  The "leapseconds" file has been updated to incorporate the most
  recent International Earth Rotation and Reference Systems Service
  (IERS) bulletin.

  There's an addition to tz-art.htm regarding the television show "Medium".


Release 2007f - 2007-05-07 10:46:46 -0400

  changes by Paul Eggert (including Haiti, Turks and Caicos, and New
  Zealand)

  changes to zic.c to allow hour values greater than 24 (along with
  Paul's improved time value overflow checking)


Release 2007e - 2007-04-02 10:11:52 -0400

  Syria and Honduras changes by Paul Eggert

  zic.c variable renaming changes by Arthur David Olson


Release 2007d - 2007-03-20 08:48:30 -0400

  changes by Paul Eggert

  the elimination of white space at the ends of lines


Release 2007c - 2007-02-26 09:09:37 -0500

  changes by Paul Eggert


Release 2007b - 2007-02-12 09:34:20 -0500

  Paul Eggert's proposed change to the quotation handling logic in zic.c.

  changes to the commentary in "leapseconds" reflecting the IERS
  announcement that there is to be no positive leap second at the end
  of June 2007.


Release 2007a - 2007-01-08 12:28:29 -0500

  changes by Paul Eggert

  Derick Rethan's Asmara change

  Oscar van Vlijmen's Easter Island local mean time change

  symbolic link changes


Release 2006p - 2006-11-27 08:54:27 -0500

  changes by Paul Eggert


Release 2006o - 2006-11-06 09:18:07 -0500

  changes by Paul Eggert


Release 2006n - 2006-10-10 11:32:06 -0400

  changes by Paul Eggert


Release 2006m - 2006-10-02 15:32:35 -0400

  changes for Uruguay, Palestine, and Egypt by Paul Eggert

  (minimalist) changes to zic.8 to clarify "until" information


Release data2006l - 2006-09-18 12:58:11 -0400

  Paul's best-effort work on this coming weekend's Egypt time change


Release 2006k - 2006-08-28 12:19:09 -0400

  changes by Paul Eggert


Release 2006j - 2006-08-21 09:56:32 -0400

  changes by Paul Eggert


Release code2006i - 2006-08-07 12:30:55 -0400

  localtime.c fixes

  Ken Pizzini's conversion script


Release code2006h - 2006-07-24 09:19:37 -0400

  adds public domain notices to four files

  includes a fix for transition times being off by a second

  adds a new recording to the "arts" file (information courtesy Colin Bowern)


Release 2006g - 2006-05-08 17:18:09 -0400

  northamerica changes by Paul Eggert


Release 2006f - 2006-05-01 11:46:00 -0400

  a missing version number problem is fixed (with thanks to Bradley
  White for catching the problem)


Release 2006d - 2006-04-17 14:33:43 -0400

  changes by Paul Eggert

  added new items to tz-arts.htm that were found by Paul


Release 2006c - 2006-04-03 10:09:32 -0400

  two sets of data changes by Paul Eggert

  a fencepost error fix in zic.c

  changes to zic.c and the "europe" file to minimize differences
  between output produced by the old 32-bit zic and the new 64-bit
  version


Release 2006b - 2006-02-20 10:08:18 -0500
  [tz32code2006b + tz64code2006b + tzdata2006b]

  64-bit code

  All SCCS IDs were bumped to "8.1" for this release.


Release 2006a - 2006-01-30 08:59:31 -0500

  changes by Paul Eggert (in particular, Indiana time zone moves)

  an addition to the zic manual page to describe how special-case
  transitions are handled


Release 2005r - 2005-12-27 09:27:13 -0500

  Canadian changes by Paul Eggert

  They also add "<pre>" directives to time zone data files and reflect
  changes to warning message logic in "zdump.c" (but with calls to
  "gettext" kept unbundled at the suggestion of Ken Pizzini).


Release 2005q - 2005-12-13 09:17:09 -0500

  Nothing earth-shaking here:
	1.  Electronic mail addresses have been removed.
	2.  Casts of the return value of exit have been removed.
	3.  Casts of the argument of is.* macros have been added.
	4.  Indentation in one section of zic.c has been fixed.
	5.  References to dead URLs in the data files have been dealt with.


Release 2005p - 2005-12-05 10:30:53 -0500

  "systemv", "tz-link.htm", and "zdump.c" changes
  (less the casts of arguments to the is* macros)


Release 2005o - 2005-11-28 10:55:26 -0500

  Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert

  zdump.c lint fixes by Arthur David Olson


Release 2005n - 2005-10-03 09:44:09 -0400

  changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
  et al. changes)


Release 2005m - 2005-08-29 12:15:40 -0400

  changes by Paul Eggert (with a small tweak to the tz-art change)

  a declaration of an unused variable has been removed from zdump.c


Release 2005l - 2005-08-22 12:06:39 -0400

  changes by Paul Eggert

  overflow/underflow checks by Arthur David Olson, minus changes to
  the "Theory" file about the pending addition of 64-bit data (I grow
  less confident of the changes being accepted with each passing day,
  and the changes no longer increase the data files nine-fold--there's
  less than a doubling in size by my local Sun's reckoning)


Release 2005k - 2005-07-14 14:14:24 -0400

  The "leapseconds" file has been edited to reflect the recently
  announced leap second at the end of 2005.

  I've also deleted electronic mail addresses from the files as an
  anti-spam measure.


Release 2005j - 2005-06-13 14:34:13 -0400

  These reflect changes to limit the length of time zone abbreviations
  and the characters used in those abbreviations.

  There are also changes to handle POSIX-style "quoted" time zone
  environment variables.

  The changes were circulated on the time zone mailing list; the only
  change since then was the removal of a couple of minimum-length of
  abbreviation checks.


Release data2005i - 2005-04-21 15:04:16 -0400

  changes (most importantly to Nicaragua and Haiti) by Paul Eggert


Release 2005h - 2005-04-04 11:24:47 -0400

  changes by Paul Eggert

  minor changes to Makefile and zdump.c to produce more useful output
  when doing a "make typecheck"


Release 2005g - 2005-03-14 10:11:21 -0500

  changes by Paul Eggert (a change to current DST rules in Uruguay and
  an update to a link to time zone software)


Release 2005f - 2005-03-01 08:45:32 -0500

  data and documentation changes by Paul Eggert


Release 2005e - 2005-02-10 15:59:44 -0500

  [not summarized]


Release code2005d - 2005-01-31 09:21:47 -0500

  make zic complain about links to links if the -v flag is used

  have "make public" do more code checking

  add an include to "localtime.c" for the benefit of gcc systems


Release 2005c - 2005-01-17 18:36:29 -0500

  get better results when mktime runs on a system where time_t is double

  changes to the data files (most importantly to Paraguay)


Release 2005b - 2005-01-10 09:19:54 -0500

  Get localtime and gmtime working on systems with exotic time_t types.

  Update the leap second commentary in the "leapseconds" file.


Release 2005a - 2005-01-01 13:13:44 -0500

  [not summarized]


Release code2004i - 2004-12-14 13:42:58 -0500

  Deal with systems where time_t is unsigned.


Release code2004h - 2004-12-07 11:40:18 -0500

  64-bit-time_t changes


Release 2004g - 2004-11-02 09:06:01 -0500

  update to Cuba (taking effect this weekend)

  other changes by Paul Eggert

  correction of the spelling of Oslo

  changed versions of difftime.c and private.h


Release code2004f - 2004-10-21 10:25:22 -0400

  Cope with wide-ranging tm_year values.


Release 2004e - 2004-10-11 14:47:21 -0400

  Brazil/Argentina/Israel changes by Paul Eggert

  changes to tz-link.htm by Paul

  one small fix to Makefile


Release 2004d - 2004-09-22 08:27:29 -0400

  Avoid overflow problems when TM_YEAR_BASE is added to an integer.


Release 2004c - 2004-08-11 12:06:26 -0400

  asctime-related changes

  (variants of) some of the documentation changes suggested by Paul Eggert


Release 2004b - 2004-07-19 14:33:35 -0400

  data changes by Paul Eggert - most importantly, updates for Argentina


Release 2004a - 2004-05-27 12:00:47 -0400

  changes by Paul Eggert

  Handle DST transitions that occur at the end of a month in some
  years but at the start of the following month in other years.

  Add a copy of the correspondence that's the basis for claims about
  DST in the Navajo Nation.


Release 2003e - 2003-12-15 09:36:47 -0500

  changes by Arthur David Olson (primarily code changes)

  changes by Paul Eggert (primarily data changes)

  minor changes to "Makefile" and "northamerica" (in the latter case,
  optimization of the "Toronto" rules)


Release 2003d - 2003-10-06 09:34:44 -0400

  changes by Paul Eggert


Release 2003c - 2003-09-16 10:47:05 -0400

  Fix bad returns in zic.c's inleap function.
  Thanks to Bradley White for catching the problem!


Release 2003b - 2003-09-16 07:13:44 -0400

  Add a "--version" option (and documentation) to the zic and zdump commands.

  changes to overflow/underflow checking in zic

  a localtime typo fix.

  Update the leapseconds and tz-art.htm files.


Release 2003a - 2003-03-24 09:30:54 -0500

  changes by Paul Eggert

  a few additions and modifications to the tz-art.htm file


Release 2002d - 2002-10-15 13:12:42 -0400

  changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab

  There's also a new time zone quote in "tz-art.htm".


Release 2002c - 2002-04-04 11:55:20 -0500

  changes by Paul Eggert

  Change zic.c to avoid creating symlinks to files that don't exist.


Release 2002b - 2002-01-28 12:56:03 -0500

  [These change notes are for Release 2002a, which was corrupted.
  2002b was a corrected version of 2002a.]

  changes by Paul Eggert

  Update the "leapseconds" file to note that there'll be no leap
  second at the end of June, 2002.

  Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.

  Change to "difftime.c" to avoid sizeof problems.


Release 2001d - 2001-10-09 13:31:32 -0400

  changes by Paul Eggert


Release 2001c - 2001-06-05 13:59:55 -0400

  changes by Paul Eggert and Andrew Brown


Release 2001b - 2001-04-05 16:44:38 -0400

  changes by Paul Eggert (modulo jnorgard's typo fix)

  tz-art.htm has been HTMLified.


Release 2001a - 2001-03-13 12:57:44 -0500

  changes by Paul Eggert

  An addition to the "leapseconds" file: comments with the text of the
  latest IERS leap second notice.

  Trailing white space has been removed from data file lines, and
  repeated spaces in "Rule Jordan" lines in the "asia" file have been
  converted to tabs.


Release 2000h - 2000-12-14 15:33:38 -0500

  changes by Paul Eggert

  one typo fix in the "art" file

  With providence, this is the last update of the millennium.


Release 2000g - 2000-10-10 11:35:22 -0400

  changes by Paul Eggert

  correction of John Mackin's name submitted by Robert Elz

  Garry Shandling's Daylight Saving Time joke (!?!) from the recent
  Emmy Awards broadcast.


Release 2000f - 2000-08-10 09:31:58 -0400

  changes by Paul Eggert

  Added information in "tz-art.htm" on a Seinfeld reference to DST.

  Error checking and messages in the "yearistype" script have been
  improved.


Release 2000e - 2000-07-31 09:27:54 -0400

  data changes by Paul Eggert

  a change to the default value of the defined constant HAVE_STRERROR

  the addition of a Dave Barry quote on DST to the tz-arts file


Release 2000d - 2000-04-20 15:43:04 -0400

  changes to the documentation and code of strftime for C99 conformance

  a bug fix for date.c

  These are based on (though modified from) changes by Paul Eggert.


Release 2000c - 2000-03-04 10:31:43 -0500

  changes by Paul Eggert


Release 2000b - 2000-02-21 12:16:29 -0500

  changes by Paul Eggert and Joseph Myers

  modest tweaks to the tz-art.htm and tz-link.htm files


Release 2000a - 2000-01-18 09:21:26 -0500

  changes by Paul Eggert

  The two hypertext documents have also been renamed.


Release code1999i-data1999j - 1999-11-15 18:43:22 -0500

  Paul Eggert's changes

  additions to the "zic" manual page and the "Arts.htm" file


Release code1999h-data1999i - 1999-11-08 14:55:21 -0500

  [not summarized]


Release data1999h - 1999-10-07 03:50:29 -0400

  changes by Paul Eggert to "europe" (most importantly, fixing
  Lithuania and Estonia)


Release 1999g - 1999-09-28 11:06:18 -0400

  data changes by Paul Eggert (most importantly, the change for
  Lebanon that buys correctness for this coming Sunday)

  The "code" file contains changes to "Makefile" and "checktab.awk" to
  allow better checking of time zone files before they are published.


Release 1999f - 1999-09-23 09:48:14 -0400

  changes by Arthur David Olson and Paul Eggert


Release 1999e - 1999-08-17 15:20:54 -0400

  changes circulated by Paul Eggert, although the change to handling
  of DST-specifying time zone names has been commented out for now
  (search for "XXX" in "localtime.c" for details).  These files also
  do not make any changes to the start of DST in Brazil.

  In addition to Paul's changes, there are updates to "Arts.htm" and
  cleanups of URLs.


Release 1999d - 1999-03-30 11:31:07 -0500

  changes by Paul Eggert

  The Makefile's "make public" rule has also been changed to do a test
  compile of each individual time zone data file (which should help
  avoid problems such as the one we had with Nicosia).


Release 1999c - 1999-03-25 09:47:47 -0500

  changes by Paul Eggert, most importantly the change for Chile.


Release 1999b - 1999-02-01 17:51:44 -0500

  changes by Paul Eggert

  code changes (suggested by Mani Varadarajan, mani at be.com) for
  correct handling of symbolic links when building using a relative directory

  code changes to generate correct messages for failed links

  updates to the URLs in Arts.htm


Release 1999a - 1999-01-19 16:20:29 -0500

  error message internationalizations and corrections in zic.c and
  zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
  to whom thanks!)


Release code1998h-data1998i - 1998-10-01 09:56:10 -0400

  changes for Brazil, Chile, and Germany

  support for use of "24:00" in the input files for the time zone compiler


Release code1998g-data1998h - 1998-09-24 10:50:28 -0400

  changes by Paul Eggert

  correction to a define in the "private.h" file


Release data1998g - 1998-08-11 03:28:35 -0000
  [tzdata1998g.tar.gz is missing!]

  Lithuanian change provided by mgedmin at pub.osf.it

  Move creation of the GMT link with Etc/GMT to "etcetera" (from
  "backward") to ensure that the GMT file is created even where folks
  don't want the "backward" links (as suggested by Paul Eggert).


Release data1998f - 1998-07-20 13:50:00 -0000
  [tzdata1998f.tar.gz is missing!]

  Update the "leapseconds" file to include the newly-announced
  insertion at the end of 1998.


Release code1998f - 1998-06-01 10:18:31 -0400

  addition to localtime.c by Guy Harris


Release 1998e - 1998-05-28 09:56:26 -0400

  The Makefile is changed to produce zoneinfo-posix rather than
  zoneinfo/posix, and to produce zoneinfo-leaps rather than
  zoneinfo/right.

  data changes by Paul Eggert

  changes from Guy Harris to provide asctime_r and ctime_r

  A usno1998 file (substantially identical to usno1997) has been added.


Release 1998d - 1998-05-14 11:58:34 -0400

  changes to comments (in particular, elimination of references to CIA maps).
  "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
  where changes occur.


Release 1998c - 1998-02-28 12:32:26 -0500

  changes by Paul Eggert (save the "French correction," on which I'll
  wait for the dust to settle)

  symlink changes

  changes and additions to Arts.htm


Release 1998b - 1998-01-17 14:31:51 -0500

  URL cleanups and additions


Release 1998a - 1998-01-13 12:37:35 -0500

  changes by Paul Eggert


Release code1997i-data1997k - 1997-12-29 09:53:41 -0500

  changes by Paul Eggert, with minor modifications from Arthur David
  Olson to make the files more browser friendly


Release code1997h-data1997j - 1997-12-18 17:47:35 -0500

  minor changes to put "TZif" at the start of each time zone information file

  a rule has also been added to the Makefile so you can
	make zones
  to just recompile the zone information files (rather than doing a
  full "make install" with its other effects).


Release data1997i - 1997-10-07 08:45:38 -0400

  changes to Africa by Paul Eggert


Release code1997g-data1997h - 1997-09-04 16:56:54 -0400

  corrections for Uruguay (and other locations)

  Arthur David Olson's simple-minded fix allowing mktime to both
  correctly handle leap seconds and correctly handle tm_sec values
  upon which arithmetic has been performed.


Release code1997f-data1997g - 1997-07-19 13:15:02 -0400

  Paul Eggert's updates

  a small change to a function prototype;

  "Music" has been renamed "Arts.htm", HTMLified, and augmented to
  include information on Around the World in Eighty Days.


Release code1997e-data1997f - 1997-05-03 18:52:34 -0400

  fixes to zic's error handling

  changes inspired by the item circulated on Slovenia

  The description of Web resources has been HTMLified for browsing
  convenience.

  A new piece of tz-related music has been added to the "Music" file.


Release code1997d-data1997e - 1997-03-29 12:48:52 -0500

  Paul Eggert's latest suggestions


Release code1997c-data1997d - 1997-03-07 20:37:54 -0500

  changes to "zic.c" to correct performance of the "-s" option

  a new file "usno1997"


Release data1997c - 1997-03-04 09:58:18 -0500

  changes in Israel


Release 1997b - 1997-02-27 18:34:19 -0500

  The data file incorporates the 1997 leap second.

  The code file incorporates Arthur David Olson's take on the
  zic/multiprocessor/directory-creation situation.


Release 1997a - 1997-01-21 09:11:10 -0500

  Paul Eggert's Antarctica (and other changes)

  Arthur David Olson finessed the "getopt" issue by checking against
  both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
  is returned while SunOS 5.5's manual says EOF is returned).


Release code1996o-data1996n - 1996-12-27 21:42:05 -0500

  Paul Eggert's latest changes


Release code1996n - 1996-12-16 09:42:02 -0500

  link snapping fix from Bruce Evans (via Garrett Wollman)


Release data1996m - 1996-11-24 02:37:34 -0000
  [tzdata1996m.tar.gz is missing!]

  Paul Eggert's batch of changes


Release code1996m-data1996l - 1996-11-05 14:00:12 -0500

  No functional changes here; the files have simply been changed to
  make more use of ISO style dates in comments. The names of the above
  files now include the year in full.


Release code96l - 1996-09-08 17:12:20 -0400

  tzcode96k was missing a couple of pieces.


Release 96k - 1996-09-08 16:06:22 -0400

  the latest round of changes from Paul Eggert

  the recent Year 2000 material


Release code96j - 1996-07-30 13:18:53 -0400

  Set sp->typecnt as suggested by Timothy Patrick Murphy.


Release code96i - 1996-07-27 20:11:35 -0400

  Paul's suggested patch for strftime %V week numbers


Release data96i - 1996-07-01 18:13:04 -0400

  "northamerica" and "europe" changes by Paul Eggert


Release code96h - 1996-06-05 08:02:21 -0400

  fix for handling transitions specified in Universal Time

  Some "public domain" notices have also been added.


Release code96g - 1996-05-16 14:00:26 -0400

  fix for the simultaneous-DST-and-zone-change challenge


Release data96h - 1996-05-09 17:40:51 -0400

  changes by Paul Eggert


Release code96f-data96g - 1996-05-03 03:09:59 -0000
  [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]

  The changes get us some of the way to fixing the problems noted in Paul
  Eggert's letter yesterday (in addition to a few others).  The approach
  has been to make zic a bit smarter about figuring out what time zone
  abbreviations apply just after the time specified in the "UNTIL" part
  of a zone line.  Putting the smarts in zic means avoiding having
  transition times show up in both "Zone" lines and "Rule" lines, which
  in turn avoids multiple transition time entries in time zone files.
  (This also makes the zic input files such as "europe" a bit shorter and
  should ease maintenance.)


Release data96f - 1996-04-19 19:20:03 -0000
  [tzdata96f.tar.gz is missing!]

  The only changes are to the "northamerica" file; the time zone
  abbreviation for Denver is corrected to MST (and MDT), and the
  comments for Mexico have been updated.


Release data96e - 1996-03-19 17:37:26 -0500

  Proposals by Paul Eggert, in particular the Portugal change that
  comes into play at the end of this month.


Release data96d - 1996-03-18 20:49:39 -0500

  [not summarized]


Release code96e - 1996-02-29 15:43:27 -0000
  [tzcode96e.tar.gz is missing!]

  internationalization changes and the fix to the documentation for strftime


Release code96d-data96c - 1996-02-12 11:05:27 -0500

  The "code" file simply updates Bob Kridle's electronic address.

  The "data" file updates rules for Mexico.


Release data96b - 1996-01-27 15:44:42 -0500

  Kiribati change


Release code96c - 1996-01-16 16:58:15 -0500

  leap-year streamlining and binary-search changes

  fix to newctime.3


Release code96b - 1996-01-10 20:42:39 -0500

  fixes and enhancements from Paul Eggert, including code that
  emulates the behavior of recent versions of the SunOS "date"
  command.


Release 96a - 1996-01-06 09:08:24 -0500

  Israel updates

  fixes to strftime.c for correct ISO 8601 week number generation,
  plus support for two new formats ('G' and 'g') to give ISO 8601 year
  numbers (which are not necessarily the same as calendar year numbers)


Release code95i-data95m - 1995-12-21 12:46:47 -0500

  The latest revisions from Paul Eggert are included, the usno1995
  file has been updated, and a new file ("WWW") covering useful URLs
  has been added.


Release code95h-data95l - 1995-12-19 18:10:12 -0500

  A simplification of a macro definition, a change to data for Sudan,
  and (for last minute shoppers) notes in the "Music" file on the CD
  "Old Man Time".


Release code95g-data95k - 1995-10-30 10:32:47 -0500

  (slightly reformatted) 8-bit-clean proposed patch

  minor patch: US/Eastern -> America/New_York

  snapshot of the USNO's latest data ("usno1995")

  some other minor cleanups


Release code95f-data95j - 1995-10-28 21:01:34 -0000
  [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]

  European cleanups

  support for 64-bit time_t's

  optimization in localtime.c


Release code95e - 1995-10-13 13:23:57 -0400

  the mktime change to scan from future to past when trying to find time zone
  offsets


Release data95i - 1995-09-26 10:43:26 -0400

  For Canada/Central, guess that the Sun customer's "one week too
  early" was just a approximation, and the true error is one month
  too early.  This is consistent with the rest of Canada.


Release data95h - 1995-09-21 11:26:48 -0400

  latest changes from Paul Eggert


Release code95d - 1995-09-14 11:14:45 -0400

  the addition of a "Music" file, which documents four recorded
  versions of the tune "Save That Time".


Release data95g - 1995-09-01 17:21:36 -0400

  "yearistype" correction


Release data95f - 1995-08-28 20:46:56 -0400

  Paul Eggert's change to the australasia file


Release data95e - 1995-07-08 18:02:34 -0400

  The only change is a leap second at the end of this year.
  Thanks to Bradley White for forwarding news on the leap second.


Release data95d - 1995-07-03 13:26:22 -0400

  Paul Eggert's changes


Release data95c - 1995-07-02 19:19:28 -0400

  changes to "asia", "backward", "europe", and "southamerica"
  (read: northamericacentrics need not apply)


Release code95c - 1995-03-13 14:00:46 -0500

  one-line fix for sign extension problems in detzcode


Release 95b - 1995-03-04 11:22:38 -0500

  Minor changes in both:

  The "code" file contains a workaround for the lack of "unistd.h" in
  Microsoft C++ version 7.

  The "data" file contains a fixed "Link" for America/Shiprock.


Release 94h - 1994-12-10 12:51:14 -0500

  The files:

  *	incorporate the changes to "zdump" and "date" to make changes to
	the "TZ" environment variable permanent;

  *	incorporate the table changes by Paul Eggert;

  *	include (and document) support for universal time specifications in
	data files - but do not (yet) include use of this feature in the
	data files.

  Think of this as "TZ Classic" - the software has been set up not to break if
  universal time shows up in its input, and data entries have been
  left as is so as not to break existing implementations.


Release data94f - 1994-08-20 12:56:09 -0400

  (with thanks!) the latest data updates from Paul Eggert


Release data94e - 1994-06-04 13:13:53 -0400

  [not summarized]


Release code94g - 1994-05-05 12:14:07 -0400

  fix missing "optind.c" and a reference to it in the Makefile


Release code94f - 1994-05-05 13:00:33 -0000
  [tzcode94f.tar.gz is missing!]

  changes to avoid overflow in difftime, as well as changes to cope
  with the 52/53 challenge in strftime


Release code94e - 1994-03-30 23:32:59 -0500

  change for the benefit of PCTS


Release 94d - 1994-02-24 15:42:25 -0500

  Avoid clashes with POSIX semantics for zones such as GMT+4.

  Some other very minor housekeeping is also present.


Release code94c - 1994-02-10 08:52:40 -0500

  Fix bug where mkdirs was broken unless you compile with
  -fwritable-strings (which is generally losing to do).


Release 94b - 1994-02-07 10:04:33 -0500

  work by Paul Eggert who notes:

  I found another book of time zone histories by E W Whitman; it's not
  as extensive as Shanks but has a few goodies of its own.  I used it
  to update the tables.  I also fixed some more as a result of
  correspondence with Adam David and Peter Ilieve, and move some stray
  links from 'europe' to 'backward'.  I corrected some scanning errors
  in usno1989.

  As far as the code goes, I fixed zic to allow years in the range
  INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
  And I cleaned up the zic documentation a little bit.


Release data94a - 1994-02-03 08:58:54 -0500

  It simply incorporates the recently announced leap second into the
  "leapseconds" file.


Release 93g - 1993-11-22 17:28:27 -0500

  Paul Eggert has provided a good deal of historic information (based
  on Shanks), and there are some code changes to deal with the buglets
  that crawled out in dealing with the new information.


Release 93f - 1993-10-15 12:27:46 -0400

  Paul Eggert's changes


Release 93e - 1993-09-05 21:21:44 -0400

  This has updated data for Israel, England, and Kwajalein.  There's
  also an update to "zdump" to cope with Kwajalein's 24-hour jump.
  Thanks to Paul Eggert and Peter Ilieve for the changes.


Release 93d - 1993-06-17 23:34:17 -0400

  new fix and new data on Israel


Release 93c - 1993-06-06 19:31:55 -0400

  [not summarized]


Release 93b - 1993-02-02 14:53:58 -0500

  updated "leapseconds" file


Release 93 - 1993-01-08 07:01:06 -0500

  At kre's suggestion, the package has been split in two - a code piece
  (which also includes documentation) that's only of use to folks who
  want to recompile things and a data piece useful to anyone who can
  run "zic".

  The new version has a few changes to the data files, a few
  portability changes, and an off-by-one fix (with thanks to
  Tom Karzes at deshaw.com for providing a description and a
  solution).


Release 92c - 1992-11-21 17:35:36 -0000
  [tz92c.tar.Z is missing!]

  The fallout from the latest round of DST transitions.

  There are changes for Portugal, Saskatchewan, and "Pacific-New";
  there's also a change to "zic.c" that makes it portable to more systems.


Release 92 - 1992-04-25 18:17:03 -0000
  [tz92.tar.Z is missing!]

  By popular demand (well, at any rate, following a request by kre at munnari)


The 1989 update of the time zone package featured:

  *	POSIXization (including interpretation of POSIX-style TZ environment
	variables, provided by Guy Harris),
  *	ANSIfication (including versions of "mktime" and "difftime"),
  *	SVIDulation (an "altzone" variable)
  *	MACHination (the "gtime" function)
  *	corrections to some time zone data (including corrections to the rules
	for Great Britain and New Zealand)
  *	reference data from the United States Naval Observatory for folks who
	want to do additional time zones
  *	and the 1989 data for Saudi Arabia.

  (Since this code will be treated as "part of the implementation" in some
  places and as "part of the application" in others, there's no good way to
  name functions, such as timegm, that are not part of the proposed ANSI C
  standard; such functions have kept their old, underscore-free names in this
  update.)

  And the "dysize" function has disappeared; it was present to allow
  compilation of the "date" command on old BSD systems, and a version of "date"
  is now provided in the package.  The "date" command is not created when you
  "make all" since it may lack options provided by the version distributed with
  your operating system, or may not interact with the system in the same way
  the native version does.

  Since POSIX frowns on correct leap second handling, the default behavior of
  the "zic" command (in the absence of a "-L" option) has been changed to omit
  leap second information from its output files.


-----
Notes

This file contains copies of the part of each release announcement
that talks about the changes in that release.  The text has been
adapted and reformatted for the purposes of this file.

Typically a release R consists of a pair of tarball files,
tzcodeR.tar.gz and tzdataR.tar.gz.  However, some releases (e.g.,
code2010a, data2012c) consist of just one or the other tarball, and a
few (e.g., code2012c-data2012d) have tarballs with mixed version
numbers.

Release time stamps are taken from the release's commit (for newer,
git releases), from the newest file in the tarball (for older
releases, where this info is available) or from the email announcing
the release (if all else fails; these are marked with a time zone of
-0000 and an "is missing!" comment).

Earlier versions of the code and data were not announced on the tz
list and are not summarized here.

This file is in the public domain.

Local Variables:
coding: utf-8
End: