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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