February 2015 - tz - lists.iana.org

proposed time zone package changes (Samoa, Factory, et al.)
by Arthur David Olson Aug. 28, 2019

Aug. 28, 2019

Below find proposed time zone package changes; the executive summary: * Makefile Change LOCALTIME default from "Factory" to "GMT"; do not compile "factory" file (but keep it in the distribution). * Theory Remove reference to "Factory" zone. * australasia Change end of DST in Samoa in 2011 from 2011-04-03 0:00 to 2011-04-03 1:00 (thanks to Raymond Hughes for a reference). * localtime.c Initialize ttinfo structures filled by tzparse (thanks to Ravindra for reporting a valgrind warning). * zic.c Fix generation of POSIX strings for zones with rules using "weekday<=n" forms of dates (thanks to Lei Liu for finding the problem). Also, limit output for non-POSIX-specificable zones defined to follow the same rules every year. (Note that no zones of either of the above types appear in the distribution; these changes cater to add-on zones). If no problems are found, 2010n will appear on 2010-10-25. --ado diff -r -c old/Makefile new/Makefile *** old/Makefile Mon Sep 27 09:24:25 2010 --- new/Makefile Tue Oct 12 12:36:50 2010 *************** *** 1,5 **** # <pre> ! # @(#)Makefile 8.8 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. --- 1,5 ---- # <pre> ! # @(#)Makefile 8.9 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. *************** *** 12,18 **** # make zonenames # to get a list of the values you can use for LOCALTIME. ! LOCALTIME= Factory # If you want something other than Eastern United States time as a template # for handling POSIX-style time zone environment variables, --- 12,18 ---- # make zonenames # to get a list of the values you can use for LOCALTIME. ! LOCALTIME= GMT # If you want something other than Eastern United States time as a template # for handling POSIX-style time zone environment variables, *************** *** 262,269 **** DOCS= README Theory $(MANS) date.1 Makefile PRIMARY_YDATA= africa antarctica asia australasia \ europe northamerica southamerica ! YDATA= $(PRIMARY_YDATA) pacificnew etcetera factory backward ! NDATA= systemv SDATA= solar87 solar88 solar89 TDATA= $(YDATA) $(NDATA) $(SDATA) TABDATA= iso3166.tab zone.tab --- 262,269 ---- DOCS= README Theory $(MANS) date.1 Makefile PRIMARY_YDATA= africa antarctica asia australasia \ europe northamerica southamerica ! YDATA= $(PRIMARY_YDATA) pacificnew etcetera backward ! NDATA= systemv factory SDATA= solar87 solar88 solar89 TDATA= $(YDATA) $(NDATA) $(SDATA) TABDATA= iso3166.tab zone.tab diff -r -c old/Theory new/Theory *** old/Theory Mon Sep 27 09:24:25 2010 --- new/Theory Tue Oct 12 12:36:50 2010 *************** *** 1,4 **** ! @(#)Theory 8.4 This file is in the public domain, so clarified as of 2009-05-17 by Arthur David Olson. --- 1,4 ---- ! @(#)Theory 8.5 This file is in the public domain, so clarified as of 2009-05-17 by Arthur David Olson. *************** *** 287,294 **** See the file `backward' for most of these older names (e.g. `US/Eastern' instead of `America/New_York'). The other old-fashioned names still supported are ! `WET', `CET', `MET', `EET' (see the file `europe'), ! and `Factory' (see the file `factory'). ----- Time zone abbreviations ----- --- 287,293 ---- See the file `backward' for most of these older names (e.g. `US/Eastern' instead of `America/New_York'). The other old-fashioned names still supported are ! `WET', `CET', `MET', and `EET' (see the file `europe'). ----- Time zone abbreviations ----- diff -r -c old/australasia new/australasia *** old/australasia Mon Sep 27 09:24:27 2010 --- new/australasia Tue Oct 12 13:14:56 2010 *************** *** 1,5 **** # <pre> ! # @(#)australasia 8.18 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. --- 1,5 ---- # <pre> ! # @(#)australasia 8.19 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. *************** *** 487,497 **** # http://www.parliament.gov.ws/documents/acts/Daylight%20Saving%20Act%20%2020… # </a> Zone Pacific/Apia 12:33:04 - LMT 1879 Jul 5 -11:26:56 - LMT 1911 -11:30 - SAMT 1950 # Samoa Time -11:00 - WST 2010 Sep 26 ! -11:00 1:00 WSDT 2011 Apr 3 -11:00 - WST # Solomon Is --- 487,507 ---- # http://www.parliament.gov.ws/documents/acts/Daylight%20Saving%20Act%20%2020… # </a> + # From Raymond Hughes (2010-10-07): + # Please see + # <a href="http://www.mcil.gov.ws"> + # http://www.mcil.gov.ws + # </a>, + # the Ministry of Commerce, Industry and Labour (sideframe) "Last Sunday + # September 2010 (26/09/10) - adjust clocks forward from 12:00 midnight + # to 01:00am and First Sunday April 2011 (03/04/11) - adjust clocks + # backwards from 1:00am to 12:00am" + Zone Pacific/Apia 12:33:04 - LMT 1879 Jul 5 -11:26:56 - LMT 1911 -11:30 - SAMT 1950 # Samoa Time -11:00 - WST 2010 Sep 26 ! -11:00 1:00 WSDT 2011 Apr 3 1:00 -11:00 - WST # Solomon Is diff -r -c old/localtime.c new/localtime.c *** old/localtime.c Mon Sep 27 09:24:26 2010 --- new/localtime.c Tue Oct 12 12:36:51 2010 *************** *** 5,11 **** #ifndef lint #ifndef NOID ! static char elsieid[] = "@(#)localtime.c 8.14"; #endif /* !defined NOID */ #endif /* !defined lint */ --- 5,11 ---- #ifndef lint #ifndef NOID ! static char elsieid[] = "@(#)localtime.c 8.15"; #endif /* !defined NOID */ #endif /* !defined lint */ *************** *** 914,919 **** --- 914,920 ---- register unsigned char * typep; register char * cp; register int load_result; + static struct ttinfo zttinfo; INITIALIZE(dstname); stdname = name; *************** *** 986,991 **** --- 987,993 ---- /* ** Two transitions per year, from EPOCH_YEAR forward. */ + sp->ttis[0] = sp->ttis[1] = zttinfo; sp->ttis[0].tt_gmtoff = -dstoffset; sp->ttis[0].tt_isdst = 1; sp->ttis[0].tt_abbrind = stdlen + 1; *************** *** 1099,1106 **** } /* ** Finally, fill in ttis. - ** ttisstd and ttisgmt need not be handled. */ sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = FALSE; sp->ttis[0].tt_abbrind = 0; --- 1101,1108 ---- } /* ** Finally, fill in ttis. */ + sp->ttis[0] = sp->ttis[1] = zttinfo; sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = FALSE; sp->ttis[0].tt_abbrind = 0; *************** *** 1113,1118 **** --- 1115,1121 ---- dstlen = 0; sp->typecnt = 1; /* only standard time */ sp->timecnt = 0; + sp->ttis[0] = zttinfo; sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = 0; sp->ttis[0].tt_abbrind = 0; diff -r -c old/zic.c new/zic.c *** old/zic.c Mon Sep 27 09:24:26 2010 --- new/zic.c Tue Oct 12 13:37:29 2010 *************** *** 3,9 **** ** 2006-07-17 by Arthur David Olson. */ ! static char elsieid[] = "@(#)zic.c 8.22"; #include "private.h" #include "locale.h" --- 3,9 ---- ** 2006-07-17 by Arthur David Olson. */ ! static char elsieid[] = "@(#)zic.c 8.24"; #include "private.h" #include "locale.h" *************** *** 1881,1896 **** register int week; if (rp->r_dycode == DC_DOWGEQ) { ! week = 1 + rp->r_dayofmonth / DAYSPERWEEK; ! if ((week - 1) * DAYSPERWEEK + 1 != rp->r_dayofmonth) return -1; } else if (rp->r_dycode == DC_DOWLEQ) { if (rp->r_dayofmonth == len_months[1][rp->r_month]) week = 5; else { ! week = 1 + rp->r_dayofmonth / DAYSPERWEEK; ! if (week * DAYSPERWEEK - 1 != rp->r_dayofmonth) return -1; } } else return -1; /* "cannot happen" */ (void) sprintf(result, "M%d.%d.%d", --- 1881,1896 ---- register int week; if (rp->r_dycode == DC_DOWGEQ) { ! if ((rp->r_dayofmonth % DAYSPERWEEK) != 1) return -1; + week = 1 + rp->r_dayofmonth / DAYSPERWEEK; } else if (rp->r_dycode == DC_DOWLEQ) { if (rp->r_dayofmonth == len_months[1][rp->r_month]) week = 5; else { ! if ((rp->r_dayofmonth % DAYSPERWEEK) != 0) return -1; + week = rp->r_dayofmonth / DAYSPERWEEK; } } else return -1; /* "cannot happen" */ (void) sprintf(result, "M%d.%d.%d", *************** *** 2018,2023 **** --- 2018,2024 ---- register char * envvar; register int max_abbr_len; register int max_envvar_len; + register int prodstic; /* all rules are min to max */ max_abbr_len = 2 + max_format_len + max_abbrvar_len; max_envvar_len = 2 * max_abbr_len + 5 * 9; *************** *** 2032,2037 **** --- 2033,2039 ---- timecnt = 0; typecnt = 0; charcnt = 0; + prodstic = zonecount == 1; /* ** Thanks to Earl Chew ** for noting the need to unconditionally initialize startttisstd. *************** *** 2053,2058 **** --- 2055,2062 ---- updateminmax(rp->r_loyear); if (rp->r_hiwasnum) updateminmax(rp->r_hiyear); + if (rp->r_lowasnum || rp->r_hiwasnum) + prodstic = FALSE; } } /* *************** *** 2075,2080 **** --- 2079,2094 ---- if (max_year <= INT_MAX - YEARSPERREPEAT) max_year += YEARSPERREPEAT; else max_year = INT_MAX; + /* + ** Regardless of any of the above, + ** for a "proDSTic" zone which specifies that its rules + ** always have and always will be in effect, + ** we only need one cycle to define the zone. + */ + if (prodstic) { + min_year = 1900; + max_year = min_year + YEARSPERREPEAT; + } } /* ** For the benefit of older systems,

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zic changes (2/2)
by Arthur David Olson March 9, 2016

March 9, 2016

And now, the update. These changes arrange things so that binary files include "transition" entries for minimum time values; these entries eliminate localtime guesswork in handling low-valued time stamps. The bad news: binary files grow slightly as a result of these changes. The good news: there are no changes in the output of "zdump -v" applied to before-and-after versions of all the binary files generated by a "make install." Changes are attached and appear in mangled form below; these are relative to the github version of zic.c after the rollback in the earlier message today. @dashdashado 1.2 2805 lines 1.4 2813 lines *** /tmp/,azic.c 2014-05-01 01:51:36.998933800 -0400 --- /tmp/,bzic.c 2014-05-01 01:51:37.092534000 -0400 *************** *** 1480,1493 **** fromi = 0; while (fromi < timecnt && attypes[fromi].at < min_time) ++fromi; - if (isdsts[0] == 0) - while (fromi < timecnt && attypes[fromi].type == 0) - ++fromi; /* handled by default rule */ for ( ; fromi < timecnt; ++fromi) { ! if (toi != 0 && ((attypes[fromi].at + gmtoffs[attypes[toi - 1].type]) <= ! (attypes[toi - 1].at + gmtoffs[toi == 1 ? 0 ! : attypes[toi - 2].type]))) { attypes[toi - 1].type = attypes[fromi].type; continue; --- 1480,1490 ---- fromi = 0; while (fromi < timecnt && attypes[fromi].at < min_time) ++fromi; for ( ; fromi < timecnt; ++fromi) { ! if (toi > 1 && ((attypes[fromi].at + gmtoffs[attypes[toi - 1].type]) <= ! (attypes[toi - 1].at + ! gmtoffs[attypes[toi - 2].type]))) { attypes[toi - 1].type = attypes[fromi].type; continue; *************** *** 1532,1537 **** --- 1529,1541 ---- --timecnt32; ++timei32; } + /* + ** Output an INT32_MIN "transition" if appropriate--see below. + */ + if (timei32 > 0 && ats[timei32] > INT32_MIN) { + --timei32; + ++timecnt32; + } while (leapcnt32 > 0 && !is32(trans[leapcnt32 - 1])) --leapcnt32; while (leapcnt32 > 0 && !is32(trans[leapi32])) { *************** *** 1698,1704 **** #undef DO for (i = thistimei; i < thistimelim; ++i) if (pass == 1) ! puttzcode(ats[i], fp); else puttzcode64(ats[i], fp); for (i = thistimei; i < thistimelim; ++i) { unsigned char uc; --- 1702,1713 ---- #undef DO for (i = thistimei; i < thistimelim; ++i) if (pass == 1) ! /* ! ** Output an INT32_MIN "transition" ! ** if appropriate--see above. ! */ ! puttzcode(((ats[i] < INT32_MIN) ? ! INT32_MIN : ats[i]), fp); else puttzcode64(ats[i], fp); for (i = thistimei; i < thistimelim; ++i) { unsigned char uc; *************** *** 2176,2183 **** if (usestart) { addtt(starttime, type); usestart = FALSE; ! } else if (stdoff != 0) ! addtt(min_time, type); } else for (year = min_year; year <= max_year; ++year) { if (useuntil && year > zp->z_untilrule.r_hiyear) break; --- 2185,2191 ---- if (usestart) { addtt(starttime, type); usestart = FALSE; ! } else addtt(min_time, type); } else for (year = min_year; year <= max_year; ++year) { if (useuntil && year > zp->z_untilrule.r_hiyear) break;

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South Australia may move clocks 30 minutes
by Paul Eggert Sept. 11, 2015

Sept. 11, 2015

The South Australian government is considering changing their clocks by 30 minutes. The government would prefer advancing clocks by 30 minutes to match the time on the east coast. The public is split. Much of the resistance is coming from the west part of the state, where locals worry about their children leaving for school in the dark, and the government is prepared to consider changing school hours to address this. Another possibility is retarding clocks by 30 minutes; this would move closer to solar time, and would align better with Asia. This change would probably affect Broken Hill as well. Northern Territory will be consulted but seems less inclined to change. The consultation process will take at least two months. The government's website crashed as citizens went online to give their opinion. Sources: Nicholson M. South Australia has the most ridiculous time zone, and might be about to change it. Junkee 2015-02-06. http://junkee.com/south-australia-has-the-most-ridiculous-time-zone-and-mig… Ball G, Clift J, Coote G. Broken Hill urged to air views on proposed time zone change for South Australia. ABC News (Australia), 2015-02-06. http://www.abc.net.au/news/2015-02-06/broken-hill-community-urged-air-views… SA considers changing time zone to match eastern states. 9NEWS 2015-02-05. http://www.9news.com.au/national/2015/02/05/12/15/sa-considers-changing-tim… South Australians remain divided on whether it is time for the time to change. 9NEWS 2015-02-06. http://www.9news.com.au/national/2015/02/06/21/03/south-australians-remain-…

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proposed tz change for Latvia, Lithuania
by Paul Eggert May 25, 2015

May 25, 2015

It's March Madness time for daylight-saving rule changes. Here's a proposed change to the tz database to keep up with the latest political development, which affects time stamps starting March 29: * Latvia and Lithuania will not observe DST, starting this year. Thanks to Andrei Ivanov for this info. =================================================================== RCS file: RCS/europe,v retrieving revision 2000.3 retrieving revision 2000.3.0.1 diff -pu -r2000.3 -r2000.3.0.1 --- europe 2000/03/04 15:31:08 2000.3 +++ europe 2000/03/08 17:48:59 2000.3.0.1 @@ -1135,6 +1135,12 @@ Link Europe/Rome Europe/San_Marino # 1997-01-21 on transition to Summer time ... established the same order of # daylight savings time settings as in the States of the European Union. +# From Andrei Ivanov (2000-03-06): +# This year Latvia will not switch to Daylight Savings Time (as specified in +# <a href="http://www.lv-laiks.lv/wwwraksti/2000/071072/vd4.htm"> +# The Regulations of the Cabinet of Ministers of the Rep. of Latvia of +# 29-Feb-2000 (#79)</a>, in Latvian for subscribers only). + # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Latvia 1989 1996 - Mar lastSun 2:00s 1:00 S Rule Latvia 1989 1996 - Sep lastSun 2:00s 0 - @@ -1151,7 +1157,8 @@ Zone Europe/Riga 1:36:24 - LMT 1880 3:00 Russia MSK/MSD 1989 Mar lastSun 2:00s 2:00 1:00 EEST 1989 Sep lastSun 2:00s 2:00 Latvia EE%sT 1997 Jan 21 - 2:00 EU EE%sT + 2:00 EU EE%sT 2000 Feb 29 + 2:00 - EET # Liechtenstein # Zone NAME GMTOFF RULES FORMAT [UNTIL] @@ -1178,6 +1185,11 @@ Zone Europe/Vaduz 0:38:04 - LMT 1894 Jun # motion to give up shifting to summer time in spring, as it was # already done by Estonia. +# From Andrei Ivanov (2000-03-06): +# I've heard that Ministers of three Baltic countries on their summit +# somewhere in February decided not to switch to summer time starting from +# this spring. + # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Vilnius 1:41:16 - LMT 1880 1:24:00 - WMT 1917 # Warsaw Mean Time @@ -1192,7 +1204,8 @@ Zone Europe/Vilnius 1:41:16 - LMT 1880 2:00 C-Eur EE%sT 1998 2:00 - EET 1998 Mar 29 1:00u 1:00 EU CE%sT 1999 Oct 31 1:00u - 2:00 EU EE%sT + 2:00 EU EE%sT 2000 Feb + 2:00 - EET # Luxembourg # Whitman disagrees with most of these dates in minor ways; go with Shanks.

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Re: [tz] Chilean time change
by Glenn Eychaner April 3, 2015

April 3, 2015

As far as I know, an official announcement of the adoption of a new time change rule would have to appear in: http://www.diariooficial.interior.gob.cl and would also appear in: http://www.horaoficial.cl/cambio_hora.html I have been monitoring both on a daily basis, and thus far have seen nothing. So for now it's unclear to me whether this is a proposal or an announcement. -G. On Feb 24, 2015, at 9:00 AM, tz-request(a)iana.org wrote: > http://www.minenergia.cl/ministerio/noticias/generales/gobierno-anuncia-mod… > I[s] this the announcement of the proposal or the announcement of the adoption of the proposal? -- Glenn Eychaner (geychaner(a)lco.cl) Telescope Systems Programmer, Las Campanas Observatory

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Chile/EasterIsland 1982 broken by 2015a?
by Stuart Bishop March 23, 2015

March 23, 2015

My test suite broke with 2015a, leading me to Chile/EasterIsland and Pacific/Easter in 1982: Chile/EasterIsland Sun Oct 11 04:00:00 1981 UT = Sat Oct 10 22:00:00 1981 EASST isdst=1 gmtoff=-21600 Chile/EasterIsland Sat Mar 13 02:59:59 1982 UT = Fri Mar 12 20:59:59 1982 EASST isdst=1 gmtoff=-21600 Chile/EasterIsland Sat Mar 13 03:00:00 1982 UT = Fri Mar 12 22:00:00 1982 EASST isdst=1 gmtoff=-18000 Chile/EasterIsland Sun Mar 14 02:59:59 1982 UT = Sat Mar 13 21:59:59 1982 EASST isdst=1 gmtoff=-18000 Chile/EasterIsland Sun Mar 14 03:00:00 1982 UT = Sat Mar 13 21:00:00 1982 EAST isdst=0 gmtoff=-21600 Chile/EasterIsland Sun Oct 10 03:59:59 1982 UT = Sat Oct 9 21:59:59 1982 EAST isdst=0 gmtoff=-21600 Chile/EasterIsland Sun Oct 10 04:00:00 1982 UT = Sat Oct 9 23:00:00 1982 EASST isdst=1 gmtoff=-18000 Chile/EasterIsland Sun Mar 13 02:59:59 1983 UT = Sat Mar 12 21:59:59 1983 EASST isdst=1 gmtoff=-18000 Did it really put the clocks forward one hour on Mar 12, then back again Mar 13? -- Stuart Bishop <stuart(a)stuartbishop.net> http://www.stuartbishop.net/

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Re: [tz] Chilean time change
by Glenn Eychaner Feb. 24, 2015

Feb. 24, 2015

As far as I know, an official announcement of the adoption of a new time change rule would have to appear in: http://www.diariooficial.interior.gob.cl and would also appear in: http://www.horaoficial.cl/cambio_hora.html I have been monitoring both on a daily basis, and thus far have seen nothing. So for now it's unclear to me whether this is a proposal or an announcement. -G. On Feb 24, 2015, at 9:00 AM, tz-request(a)iana.org wrote: > http://www.minenergia.cl/ministerio/noticias/generales/gobierno-anuncia-mod… > I[s] this the announcement of the proposal or the announcement of the adoption of the proposal? -- Glenn Eychaner (geychaner(a)lco.cl) Telescope Systems Programmer, Las Campanas Observatory

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Chilean time change
by Glenn Eychaner Feb. 23, 2015

Feb. 23, 2015

I have been following Diario Official for the past couple of weeks (http://www.diariooficial.interior.gob.cl) and have yet to see an official announcement regarding the change of time zone rules. In addition, SHOA has yet to update their web site (http://www.horaoficial.cl/cambio_hora.html) -G. -- Glenn Eychaner (geychaner(a)lco.cl) Telescope Systems Programmer, Las Campanas Observatory

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An outline of a possible solution for sensible leap-second support.
by random832＠fastmail.us Feb. 16, 2015

Feb. 16, 2015

Right now, very few people use the leap second support in tzcode. This may represent a lack of demand, or it may be due to the fact that you cannot have both leap second support and POSIX compliance at the same time. Even when people do use it, it's often done in an incomplete and incorrect way (e.g. by specifying the "right" folder directly in the TZ variable). If the tz project intends to provide leap second support, I would argue that it should be in a form that people can actually use. Also, general question: is there any standard on how leap seconds are to be handled in timezones that have an offset that is not a multiple of one whole minute? What does tzcode do now? ---- Abandon entirely the time2posix/posix2time functions, the "right" directory, and the notion of a time_t representation where e.g. 2000-01-01T00:00:00Z is represented by a value of 946684822 rather than 946684800. Very few people use them, and many of those who do use them do so incorrectly even disregarding the issue of programs they may run that do not call the conversion functions when they should. Remove support for generating tzdata files with leap second data, and report an error if one is loaded. Create a non-ambiguous representation for leap-aware timestamps. My suggestion is a pair of {time_t time; int leap;}, with time being (for leap seconds) the POSIX timestamp for the preceding normal second, and leap=1 for s=60, leap=2 for s=61, etc. Define a function interface which leap-aware systems may use to return the correct time, with leap seconds and without any skew to attempt to compensate for them. Tzcode to contain a dummy version that returns {time, 0}. The value of the existing time() function around leap seconds (e.g. whether it reports 23:59:59 twice, 00:00:00 twice, or implements some form of skew over the course of the minute/hour/day) is implementation-defined. (Arguably this new interface should also return the best known correct time immediately rather than implementing skew in the case of NTP adjustments as well, since unlike time() it is not expected to be used by legacy programs as a pseudo-monotonic counter) Define a file format and location (e.g. zoneinfo/leapdb) to store a single copy of leap second information for use by the following functions. Define leap-aware interval-measurement (difftime) and interval-addition (+ and - operator) functions. For example, since there was a leap second in June 2012, difftime_l({1341100802, 0}, {1341100798, 0}) [2012-07-01T00:00:02Z minus 2012-06-30T23:59:58Z] is 5 rather than the conventional 4. This is in contrast to the current implementation which represents these times with different values that differ by 5, and implements difftime by simple subtraction. Define leap-aware versions of mktime_r, localtime_r, mktime_rz, localtime_rz, gmtime_r, timegm_r, which use the new representation where the normal ones use time_t. Expanded scope (not part of tzcode/tzdata itself) - provide recommendations of how to represent leap second times in filesystem structures, archive structures, struct stat, struct timespec, and to maintain backwards compatibility with existing ABIs which do not provide this information (extending the range of an existing sub-second field is worth considering in some cases, though 32-bit signed nanoseconds only have room for one additional second in this way.)

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leap second insertions
by Nathan Justus Feb. 16, 2015

Feb. 16, 2015

>One additional second is all one needs, no? Two leap seconds are never inserted adjacent to each other. So POSIX's 'struct timespec' suffices to >represent leap seconds, and there's no need for a new data type here, just new operations on the type. You could start by adding a new clock to >clock_gettime, a clock that respects leap seconds. There has never been more than one leap second added in any one instance, but as far as I know, nothing precludes adding more than one at any one time. But, I daresay there would be a really significant event that would cause it, such as an asteroid strike that affect the day :) Nathan

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The zoneinfo file system tree structure ?
by J William Piggott Feb. 13, 2015

Feb. 13, 2015

[please cc me, I am not subscribed] Hello, I have been working on Util-linux' hwclock and other GNU/Linux date-time issues. I have a couple of questions that I hope someone here can answer. The tz database file system tree was changed on May 25 1998, moving 'right' and 'posix' from subdirectories of zoneinfo to sibling directories. However GNU libc continued to use the old structure until it stopped including the data files on Mar 7 2012. Now some Linux distributions are still using the old subdirectory tree structure. Is there a reason that the old tree structure is still being used? Does it break something to have 'right' and 'posix' as sibling directories? I ask because the problems that were the catalyst for the change in 1998 are still happening. It seems to me like it was a good solution, but nobody used it. If I may ask one more favor, could you please review the information below which I have added to the hwclock man-page? I still need to include information about using TZDIR. Thank you very much, William POSIX vs 'RIGHT' A discussion on date-time configuration would be incomplete without addressing timezones, this is mostly well covered by tzset(3). One area that seems to have no documentation is the 'right' directory of the IANA Time Zone Database, aka tz, aka zoneinfo. There are two separate databases in the zoneinfo system, posix and 'right'. 'Right' (now named leaps) includes leap seconds and posix does not. To use the 'right' database the System Clock must be kept in UTC + leap_seconds, i.e., TAI - 10. This allows calculating the exact number of seconds between two dates that cross a leap second epoch. The System Clock is then converted to the correct civil time, including UTC, by using the 'right' timezone files which subtract the leap sec- onds. Note: this configuration is considered experimental and is known to have issues. To configure a system to use a particular database all of the files located in its directory must be copied to the root of /usr/share/zoneinfo. Files are never used directly from the posix or 'right' subdirectories, e.g., TZ='right/Europe/Dublin'. This habit was becoming so common that the upstream zoneinfo project restructured the system's file tree by moving the posix and 'right' subdirectories out of the zoneinfo directory and into sibling directories: /usr/share/zoneinfo /usr/share/posix /usr/share/leaps Unfortunately, some Linux distributions are changing it back to the old tree structure in their packages. So the problem of system administra- tors reaching into the 'right' subdirectory persists. This causes the system timezone to be configured to include leap seconds while the zoneinfo database is still configured to exclude them. Then when an application such as a World Clock needs the South_Pole timezone file; or an email MTA, or hwclock needs the UTC timezone file; they fetch it from the root of /usr/share/zoneinfo , because that is what they are supposed to do. Those files exclude leap seconds, but the System Clock now includes them, causing an incorrect time conversion. Attempting to mix and match files from these separate databases will not work, because they each require the System Clock to use a different timescale. The zoneinfo database must be configured to use either posix or 'right', as described above.

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[PROPOSED PATCH] * northamerica (America/Cayman): Put Link after Zone.
by Paul Eggert Feb. 13, 2015

Feb. 13, 2015

--- northamerica | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/northamerica b/northamerica index cb27bd5..77463da 100644 --- a/northamerica +++ b/northamerica @@ -2592,7 +2592,7 @@ Zone Atlantic/Bermuda -4:19:18 - LMT 1930 Jan 1 2:00 # Hamilton -4:00 US A%sT # Cayman Is -Link America/Panama America/Cayman +# See America/Panama. # Costa Rica @@ -3115,6 +3115,7 @@ Zone America/Managua -5:45:08 - LMT 1890 Zone America/Panama -5:18:08 - LMT 1890 -5:19:36 - CMT 1908 Apr 22 # Colón Mean Time -5:00 - EST +Link America/Panama America/Cayman # Puerto Rico # There are too many San Juans elsewhere, so we'll use 'Puerto_Rico'. -- 2.1.0

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[PROPOSED PATCH] Move four out-of-scope zones to 'backzone'
by Paul Eggert Feb. 13, 2015

Feb. 13, 2015

* NEWS: Document this. * australasia (Pacific/Guam): Now a link to Pacific/Guam. (Pacific/Midway): Now a link to Pacific/Pago_Pago. * backzone (America/Antigua, America/Cayman, Pacific/Miday) (Pacific/Saipan): Move these four entries here from the other files. * checktab.awk: Remove special cases for the four zones. * northamerica (America/Cayman): Now a link to America/Panama. (America/Antigua): Move to ... * southamerica (America/Antigua): ... here, and make it a link to America/Port_of_Spain. --- NEWS | 9 +++++++++ australasia | 27 ++++----------------------- backzone | 36 ++++++++++++++++++++++++++++++++++++ checktab.awk | 9 --------- northamerica | 12 ++---------- southamerica | 1 + 6 files changed, 52 insertions(+), 42 deletions(-) diff --git a/NEWS b/NEWS index b70ce73..33e983f 100644 --- a/NEWS +++ b/NEWS @@ -2,6 +2,15 @@ News for the tz database Unreleased, experimental changes + Changes affecting past time stamps + + 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: America/Antigua, America/Cayman, + Pacific/Midway, and Pacific/Saipan. + Changes affecting commentary Cite the recent Mexican decree changing Quintana Roo's time zone. diff --git a/australasia b/australasia index 911e681..3e2c0b3 100644 --- a/australasia +++ b/australasia @@ -373,6 +373,7 @@ Zone Pacific/Guam -14:21:00 - LMT 1844 Dec 31 9:39:00 - LMT 1901 # Agana 10:00 - GST 2000 Dec 23 # Guam 10:00 - ChST # Chamorro Standard Time +Link Pacific/Guam Pacific/Saipan # N Mariana Is # Kiribati # Zone NAME GMTOFF RULES FORMAT [UNTIL] @@ -388,12 +389,7 @@ Zone Pacific/Kiritimati -10:29:20 - LMT 1901 14:00 - LINT # N Mariana Is -# Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone Pacific/Saipan -14:17:00 - LMT 1844 Dec 31 - 9:43:00 - LMT 1901 - 9:00 - MPT 1969 Oct # N Mariana Is Time - 10:00 - MPT 2000 Dec 23 - 10:00 - ChST # Chamorro Standard Time +# See Pacific/Guam. # Marshall Is # Zone NAME GMTOFF RULES FORMAT [UNTIL] @@ -563,6 +559,7 @@ Zone Pacific/Pago_Pago 12:37:12 - LMT 1879 Jul 5 -11:00 - NST 1967 Apr # N=Nome -11:00 - BST 1983 Nov 30 # B=Bering -11:00 - SST # S=Samoa +Link Pacific/Pago_Pago Pacific/Midway # in US minor outlying islands # Samoa (formerly and also known as Western Samoa) @@ -744,23 +741,7 @@ Zone Pacific/Funafuti 11:56:52 - LMT 1901 # uninhabited # Midway -# -# From Mark Brader (2005-01-23): -# [Fallacies and Fantasies of Air Transport History, by R.E.G. Davies, -# published 1994 by Paladwr Press, McLean, VA, USA; ISBN 0-9626483-5-3] -# reproduced a Pan American Airways timetable from 1936, for their weekly -# "Orient Express" flights between San Francisco and Manila, and connecting -# flights to Chicago and the US East Coast. As it uses some time zone -# designations that I've never seen before:.... -# Fri. 6:30A Lv. HONOLOLU (Pearl Harbor), H.I. H.L.T. Ar. 5:30P Sun. -# " 3:00P Ar. MIDWAY ISLAND . . . . . . . . . M.L.T. Lv. 6:00A " -# -Zone Pacific/Midway -11:49:28 - LMT 1901 - -11:00 - NST 1956 Jun 3 - -11:00 1:00 NDT 1956 Sep 2 - -11:00 - NST 1967 Apr # N=Nome - -11:00 - BST 1983 Nov 30 # B=Bering - -11:00 - SST # S=Samoa +# See Pacific/Pago_Pago. # Palmyra # uninhabited since World War II; was probably like Pacific/Kiritimati diff --git a/backzone b/backzone index fc20ea5..31a3f5a 100644 --- a/backzone +++ b/backzone @@ -255,6 +255,11 @@ Zone Africa/Timbuktu -0:12:04 - LMT 1912 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2 -4:00 - AST +# Antigua and Barbuda +Zone America/Antigua -4:07:12 - LMT 1912 Mar 2 + -5:00 - EST 1951 + -4:00 - AST + # Chubut, Argentina # The name "Comodoro Rivadavia" exceeds the 14-byte POSIX limit. Zone America/Argentina/ComodRivadavia -4:30:00 - LMT 1894 Oct 31 @@ -274,6 +279,11 @@ Zone America/Aruba -4:40:24 - LMT 1912 Feb 12 # Oranjestad -4:30 - ANT 1965 # Netherlands Antilles Time -4:00 - AST +# Cayman Is +Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown + -5:07:11 - KMT 1912 Feb # Kingston Mean Time + -5:00 - EST + # Canada Zone America/Coral_Harbour -5:32:40 - LMT 1884 -5:00 NT_YK E%sT 1946 @@ -599,3 +609,29 @@ Zone Indian/Mayotte 3:00:56 - LMT 1911 Jul # Mamoutzou # US minor outlying islands Zone Pacific/Johnston -10:00 - HST + +# US minor outlying islands +# +# From Mark Brader (2005-01-23): +# [Fallacies and Fantasies of Air Transport History, by R.E.G. Davies, +# published 1994 by Paladwr Press, McLean, VA, USA; ISBN 0-9626483-5-3] +# reproduced a Pan American Airways timetable from 1936, for their weekly +# "Orient Express" flights between San Francisco and Manila, and connecting +# flights to Chicago and the US East Coast. As it uses some time zone +# designations that I've never seen before:.... +# Fri. 6:30A Lv. HONOLOLU (Pearl Harbor), H.I. H.L.T. Ar. 5:30P Sun. +# " 3:00P Ar. MIDWAY ISLAND . . . . . . . . . M.L.T. Lv. 6:00A " +# +Zone Pacific/Midway -11:49:28 - LMT 1901 + -11:00 - NST 1956 Jun 3 + -11:00 1:00 NDT 1956 Sep 2 + -11:00 - NST 1967 Apr # N=Nome + -11:00 - BST 1983 Nov 30 # B=Bering + -11:00 - SST # S=Samoa + +# N Mariana Is +Zone Pacific/Saipan -14:17:00 - LMT 1844 Dec 31 + 9:43:00 - LMT 1901 + 9:00 - MPT 1969 Oct # N Mariana Is Time + 10:00 - MPT 2000 Dec 23 + 10:00 - ChST # Chamorro Standard Time diff --git a/checktab.awk b/checktab.awk index 9a452b6..cf2c726 100644 --- a/checktab.awk +++ b/checktab.awk @@ -12,15 +12,6 @@ BEGIN { # A special (and we hope temporary) case. tztab["America/Montreal"] = 1 - # Some more special cases; these are zones that should probably - # be turned into links. - if (zone_table == "zone1970.tab") { - tztab["America/Antigua"] = 1 - tztab["America/Cayman"] = 1 - tztab["Pacific/Midway"] = 1 - tztab["Pacific/Saipan"] = 1 - } - while (getline <iso_table) { iso_NR++ if ($0 ~ /^#/) continue diff --git a/northamerica b/northamerica index ad7e106..cb27bd5 100644 --- a/northamerica +++ b/northamerica @@ -2524,13 +2524,8 @@ Zone America/Santa_Isabel -7:39:28 - LMT 1922 Jan 1 0:20:32 ############################################################################### # Anguilla -# See America/Port_of_Spain. - # Antigua and Barbuda -# Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone America/Antigua -4:07:12 - LMT 1912 Mar 2 - -5:00 - EST 1951 - -4:00 - AST +# See America/Port_of_Spain. # Bahamas # @@ -2597,10 +2592,7 @@ Zone Atlantic/Bermuda -4:19:18 - LMT 1930 Jan 1 2:00 # Hamilton -4:00 US A%sT # Cayman Is -# Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown - -5:07:11 - KMT 1912 Feb # Kingston Mean Time - -5:00 - EST +Link America/Panama America/Cayman # Costa Rica diff --git a/southamerica b/southamerica index a64a438..fc0cc54 100644 --- a/southamerica +++ b/southamerica @@ -1604,6 +1604,7 @@ Zone America/Port_of_Spain -4:06:04 - LMT 1912 Mar 2 # These all agree with Trinidad and Tobago since 1970. Link America/Port_of_Spain America/Anguilla +Link America/Port_of_Spain America/Antigua Link America/Port_of_Spain America/Dominica Link America/Port_of_Spain America/Grenada Link America/Port_of_Spain America/Guadeloupe -- 2.1.0

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Brazil considering delay to end of DST
by Paul Eggert Feb. 12, 2015

Feb. 12, 2015

The government of Brazil is considering ending daylight saving time later than planned. Currently DST is scheduled to end February 22 at 00:00 local time. This may be delayed by a month. A decision is planned by February 12. Brazil is getting less rain than expected -- their January was the driest in 85 years -- and hydroelectric plants produce most of Brazil's electricity. The hope is that daylight saving time will lower power consumption peaks, making power blackouts less likely. Sources: Jelmayer R. Brazil evaluates extending daylight saving time. Dow Jones Business News 2015-02-06. http://www.nasdaq.com/article/brazil-evaluates-extending-daylight-saving-ti… Governo estuda estender o horário de verão para economizar energia. Jornal Nacional 2015-02-05. http://g1.globo.com/economia/noticia/2015/02/governo-estuda-estender-o-hora… Watts J. Brazil’s worst drought in history prompts protests and blackouts. The Guardian 2015-01-23. http://www.theguardian.com/world/2015/jan/23/brazil-worst-drought-history

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tz-latest checksum
by Paul G Feb. 7, 2015

Feb. 7, 2015

I'm looking into writing a python script which retrieves the latest timezone database from the FTP server, but I'm wondering if there's anywhere that a checksum of the tz-latest files can be found anywhere. At the moment, we manually specify the latest version of the database, and calculate the sha512 checksum whenever it is updated. I see that the GPG signature is available, but I would very much like to avoid adding any dependencies to the library. Is there anywhere that I retrieve the checksum for the latest tzdata file using one of the hashes supported by hashlib? (SHA1, SHA256, SHA384, SHA512 or MD5) Of course this defeats the implied MITM protection that retrieving a "known good" or signed checksum provides, but it at least retains the checksum / corrupted file protection. Thanks!

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Re: [tz] Positive leap second on 2015-06-30.
by Denis Excoffier Feb. 7, 2015

Feb. 7, 2015

On 2015-01-06 21:22, Tim Parenti wrote: > +# Some systems implement leap seconds by amortizing the leap second > +# over the last few minutes of the day. The frequency of the local > +# clock is decreased (or increased) to realize the positive (or > +# negative) leap second. This method removes the time step described > +# above. Although the long-term behavior of the time scale is correct > +# in this case, this method introduces an error during the adjustment > +# period both in time and in frequency with respect to the official > +# defintion of UTC. s/defintion/definition/ Regards, Denis Excoffier.

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Chilean time change
by Glenn Eychaner Feb. 7, 2015

Feb. 7, 2015

I have been following Diario Official for the past couple of weeks (http://www.diariooficial.interior.gob.cl) and have yet to see an official announcement regarding the change of time zone rules. In addition, SHOA has yet to update their web site (http://www.horaoficial.cl/cambio_hora.html) -G. -- Glenn Eychaner (geychaner(a)lco.cl) Telescope Systems Programmer, Las Campanas Observatory

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Re: [tz] Fwd: Quintana Roo change to EST?
by Matt Johnson Feb. 7, 2015

Feb. 7, 2015

The CENAM belongs to the Economic Secretary. My understanding is that this is the official department that would set the policy - similar to NIST in the US. ________________________________ From: Paul Eggert<mailto:eggert@cs.ucla.edu> Sent: ‎2/‎5/‎2015 4:29 PM To: Matt Johnson<mailto:mj1856@hotmail.com>; Time Zone Database<mailto:tz@iana.org> Subject: Re: [tz] Fwd: Quintana Roo change to EST? There were conflicting reports about this back when Mexico was considering doing the change in October of this year. As I understand it, Mexico decided to move the change up to this month, and to stay on EST all year. For a brief summary please see: http://www.timeanddate.com/news/time/mexico-quintana-roo-time-zone.html It could well be that this is wrong. There's at least one English-language source saying that it hasn't been decided whether Quintana Roo will observe DST: http://www.blogsouthwest.com/who-moved-my-queso-cancun-changes-time-zone/ and perhaps we'll need a further update once this becomes decided or sufficiently clear. That being said, my (admittedly limited) understanding of QRoo politics suggests that they won't observe DST this year. That CENAM web page is reasonably generic and perhaps its author didn't think about (or want to think about) predicting exactly what will happen in April.

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Fwd: Quintana Roo change to EST?
by Gwillim Law Feb. 6, 2015

Feb. 6, 2015

My translation of the cited article: "... the new time zone will come into effect at two o'clock on the first Sunday of February, when we will have to advance the clock one hour from its current time, ... "Federal deputy Lizbeth Gamboa Song stated that a new change for the month of April is not considered as yet, given that only the State will advance to summer time. "Nevertheless, the deputy noted that Summer Time has applied in Mexico since 1996, to which all entities of the federation adhere, advancing their clocks one hour. In addition, she noted that it is yet unknown whether Quintana Roo will participate in a further change, but if so, the authorities will officially publish that fact in due time." My Spanish is not native level, but I think the article makes it clear that the decision about DST for Quintana Roo has not yet been made. Gwillim Law On Wed, Jan 14, 2015 at 10:43 AM, Steffen Thorsen <thorsen(a)timeanddate.com> wrote: > On 08/12/14 14:18 , Steffen Thorsen wrote: > >> The Mexican state of Quintana Roo will likely change to EST in 2015, by >> not >> going back from DST in October 2015. Its a bit unclear if they will still >> observe >> DST the years after. >> > According to this source, Quintana Roo will change to EST as soon as 1 > February 2015 at 2am: > http://sipse.com/novedades/confirman-aplicacion-de-nueva- > zona-horaria-para-quintana-roo-132331.html > > Through Google Translate, it says "According to the authorities, the term > of the new time zone start at two o'clock on the first Sunday of February, > when we brought forward one hour actual[?] hours, so the clock will be > three o'clock." > > Also, the new zone will not use DST. > > > Best regards, > Steffen Thorsen - timeanddate.com >

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US DST Legislation
by Ray at the Time Zone Report Feb. 4, 2015

Feb. 4, 2015

Greetings, I'm new to the TZ list, but wanted to mention that I've got several venues where I provide pending legislation information relating to Daylight Saving Time and Time Zones in the US. There's a full set of statuses at http://TimeZoneReport.com updated daily, plus Twitter, Facebook, and podcast feeds. In case you haven't heard, an Interesting DST news day yesterday: * Washington state Representative Elizabeth Scott spoke before the House State Government Committee yesterday, and brief discussion on her bill HB 1479 was on the positive side. * Mississippi's SB 2180 for Year-Round DST died in the Senate Rules Committee. * I received a call from the US Department of Transportation Office of the General Counsel, and he provided information which I will summarize on the web site later today. Bottom line: states can opt out of DST, or they can stay with DST as defined in 15 USC 260a - no other option is permitted, such as Year-Round DST; and US DOT is unlikely to approve any state's request to change time zones. * Utah has a NEW bill HB 247 proposing to simply move to Central Time, in sort of a "why ask for permission" move, filed yesterday at 4:55pm. The legislative review note mentions the "high probability that a court will hold that the bill is preempted by federal law and is unconstitutional under the Supremacy Clause". so they know this bill is doomed. * A Missouri Representative has filed House Joint Resolution 38 intending to submit to voters an initiative which "establishes daylight saving time as new standard time", if passed. Sort of a "we're just going to move the clocks forward and call that 'standard time' from now on." With Mississippi dropping out plus the addition of Missouri, there are still nine US States with active DST/TZ legislation pending. Ray ----- Ray Harwood Time Zone Report, a service of GoodClix, Inc. in the interest of public health <http://www.TimeZoneReport.com> http://www.TimeZoneReport.com and Twitter: @TimeZoneReport

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Oregon to reconsider DST
by Matt Johnson Feb. 4, 2015

Feb. 4, 2015

If passed, Oregon SB99 would repeal DST - effective 2021. Wouldn't it be nice if all DST changes gave such ample notice! Bill, including full text:https://olis.leg.state.or.us/liz/2015R1/Measures/Overview/SB99 Found courtesy of M3 Sweatt at Microsofthttp://blogs.msdn.com/b/mthree/archive/2015/02/02/oregondst-020215…

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MSFT open-sourced CoreCLR, timezone bits inside
by Andrew Paprocki Feb. 3, 2015

Feb. 3, 2015

For anyone that is interested, Microsoft open-sourced the .NET CoreCLR: https://github.com/dotnet/coreclr Inside are the bits that read Microsoft's timezone data from the registry and provide the .NET interface: https://github.com/dotnet/coreclr/blob/master/src/mscorlib/src/System/TimeZ… -Andrew

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