September 2013 - tz - lists.iana.org

TAI as a time zone?
by DataPacRat Sept. 15, 2013

Sept. 15, 2013

Would it be feasible to include International Atomic Time (TAI) and/or GPS time (which differs from TAI by a fixed number of seconds) in the tz database as a time zone separate from UTC? I ask because I'm getting ready to submit at least one calendar to BCP 47 which is based on the leap-second-free TAI, and from the feedback I've gotten so far, it seems that the most widely-acceptable way to deal with the differences between TAI and UTC is to employ the tz database, if it's possible to do so. -- Thank you for your time, -- DataPacRat

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Question about leap seconds
by random832＠fastmail.us Sept. 12, 2013

Sept. 12, 2013

Two things: Can a transition time ever reasonably fall _on_ a leap second, and can the zic input format represent this case? I am sketching out a design for a new time zone file format, and it occurs to me that it might be a good idea to specify transitions with POSIX timestamps so the data regarding one time zone is independent of whether leap seconds are enabled or not.

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Re: [tz] Using MediaWiki / Wikidata
by Lester Caine Sept. 12, 2013

Sept. 12, 2013

Tobias Conradi wrote: > was: Re: [tz] [PATCH 3/3] * europe (Europe/Vaduz): Now a link to Europe/Zurich. > > On Tue, Sep 10, 2013 at 7:29 PM, Paul Eggert <eggert(a)cs.ucla.edu> wrote: >> It may well make sense to organize what is currently tz commentary >> into something that is, well, a bit more organized. The format >> I'm most familiar with is MediaWiki, for what it's worth. > And here is some infrastructure using MediaWiki: > https://en.wikipedia.org/wiki/Category:Tz_database > > E.g. > https://en.wikipedia.org/wiki/Africa/Luanda > https://en.wikipedia.org/wiki/America/Indiana/Indianapolis > https://en.wikipedia.org/wiki/Asia/Novosibirsk > > But there are vandalizing admins around, e.g. Anthony Bradbury: > https://en.wikipedia.org/w/index.php?title=Special:Log&page=Time+in+Africa > > Another option could be to use wikidata, e.g. > Asia/Novosibirsk > https://www.wikidata.org/wiki/Q4806295 > and put evidences and for time offsets there. Personally I have no time for wikipedia since we had a lot of well written material removed in the past because some other editors decided they did not like it. So I have no confidence that any material posted would remain clean or even available. I think that a 'private' wiki is much more appropriate given that what we are going to archive is evidential material? With publicly accessible sandboxes for providing new material. Which is then managed based on it's suitability for inclusion? I could live with mediawiki format, but I much prefer clean html documents using ckeditor. And adding interactive packages is something I don't find particularly easy with those type of systems anyway. Is there somewhere appropriate to host a service Paul? I'm happy to run something on my servers, but I suspect the load may be quite high ;) -- Lester Caine - G8HFL ----------------------------- Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk Rainbow Digital Media - http://rainbowdigitalmedia.co.uk

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[PATCH 1/3] Fix off-by-one bug with Kingston Mean Time.
by Paul Eggert Sept. 12, 2013

Sept. 12, 2013

* northamerica (America/Cayman, America/Jamaica, America/Grand_Turk): Change KMT from -5:07:12 to -5:07:11 (should be -5:07:10.41). * zone.tab: Fine-tune geographical coordinates to match -5:07:10.41. I chose the latitude to match the General Post Office, Kingston, in the city center according to Google Maps. --- northamerica | 19 +++++++------------ zone.tab | 2 +- 2 files changed, 8 insertions(+), 13 deletions(-) diff --git a/northamerica b/northamerica index 3a572ba..55755dd 100644 --- a/northamerica +++ b/northamerica @@ -2622,7 +2622,7 @@ Zone Atlantic/Bermuda -4:19:18 - LMT 1930 Jan 1 2:00 # Hamilton # Cayman Is # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown - -5:07:12 - KMT 1912 Feb # Kingston Mean Time + -5:07:11 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST # Costa Rica @@ -3067,17 +3067,12 @@ Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr # Great Swan I ceded by US to Honduras in 1972 # Jamaica - -# From Bob Devine (1988-01-28): -# Follows US rules. - -# From U. S. Naval Observatory (1989-01-19): -# JAMAICA 5 H BEHIND UTC - -# From Shanks & Pottenger: +# Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an +# unspecified official document, and says "This time is used throughout the +# island". Go with Milne. Round to the nearest second as required by zic. # Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston - -5:07:12 - KMT 1912 Feb # Kingston Mean Time +Zone America/Jamaica -5:07:11 - LMT 1890 # Kingston + -5:07:11 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST 1974 Apr 28 2:00 -5:00 US E%sT 1984 -5:00 - EST @@ -3217,7 +3212,7 @@ Rule TC 2007 max - Mar Sun>=8 2:00 1:00 D Rule TC 2007 max - Nov Sun>=1 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Grand_Turk -4:44:32 - LMT 1890 - -5:07:12 - KMT 1912 Feb # Kingston Mean Time + -5:07:11 - KMT 1912 Feb # Kingston Mean Time -5:00 TC E%sT # British Virgin Is diff --git a/zone.tab b/zone.tab index 769432b..7d4c575 100644 --- a/zone.tab +++ b/zone.tab @@ -233,7 +233,7 @@ IR +3540+05126 Asia/Tehran IS +6409-02151 Atlantic/Reykjavik IT +4154+01229 Europe/Rome JE +4912-00207 Europe/Jersey -JM +1800-07648 America/Jamaica +JM +175805-0764736 America/Jamaica JO +3157+03556 Asia/Amman JP +353916+1394441 Asia/Tokyo KE -0117+03649 Africa/Nairobi -- 1.8.3.1

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Re: [tz] uniform time in Switzerland in second half of 19th century
by Paul Eggert Sept. 12, 2013

Sept. 12, 2013

Pierre-Yves Berger found some documentary evidence of the 1894 transition in Switzerland, and I got my hands on a copy of Messerli's book, which gives more details about the circa-1855 transition. Here's a patch, which I'll push to the experimental repository. As far as data goes, this merely moves the 1855 transition to 1853-07-16. >From 9805c5c4a38750ff0c2345fdcc2a273357153259 Mon Sep 17 00:00:00 2001 From: Paul Eggert <eggert(a)cs.ucla.edu> Date: Wed, 11 Sep 2013 18:28:36 -0700 Subject: [PATCH] * europe, zic.8 (Europe/Zurich): Change transition to 1853-07-16. Explain how I derived this guess from Messerli's book. Also, give better evidence about the 1894 transition, from Pierre-Yves Berger. --- europe | 39 ++++++++++++++++++++++++++++----------- zic.8 | 6 +++--- 2 files changed, 31 insertions(+), 14 deletions(-) diff --git a/europe b/europe index 8d26b4e..e70cfb4 100644 --- a/europe +++ b/europe @@ -2662,23 +2662,40 @@ Zone Europe/Stockholm 1:12:12 - LMT 1879 Jan 1 # ... the meridian for Bern mean time ... is 7 degrees 26'22.50". # Expressed in time, it is 0h29m45.5s. +# From Pierre-Yves Berger (2013-09-11): +# the "Circulaire du conseil federal" (December 11 1893) +# <http://www.amtsdruckschriften.bar.admin.ch/viewOrigDoc.do?id=10071353> ... +# clearly states that the [1894-06-01] change should be done at midnight +# but if no one is present after 11 at night, could be postponed until one +# hour before the beginning of service. + # From Paul Eggert (2013-09-11): -# Round to the nearest even second, 0:29:46. -# -# We can find no reliable source for Shanks's claim that all of Switzerland -# except Geneva switched to Bern Mean Time at 00:00 on 1848-09-12. On the -# contrary, a more-reliable source talks about "the gradual introduction of a -# national time (from the 1850s)" (Google translation) with a switch to CET in -# 1894; see Speich's review of Messerli's thesis, Traverse 1997/3, 131-3 -# <http://www.tg.ethz.ch/dokumente/pdf_files/rez_messerli.pdf>. For now, model -# this messy process as a transition in 1855. Shanks's 1894 transition is more -# plausible for Zurich but has not been checked. +# Round BMT to the nearest even second, 0:29:46. +# +# We can find no reliable source for Shanks's assertion that all of Switzerland +# except Geneva switched to Bern Mean Time at 00:00 on 1848-09-12. This book: +# +# Jakob Messerli. Gleichmassig, punktlich, schnell: Zeiteinteilung und +# Zeitgebrauch in der Schweiz im 19. Jahrhundert. Chronos, Zurich 1995, +# ISBN 3-905311-68-2, OCLC 717570797. +# +# suggests that the transition was more gradual, and that the Swiss did not +# agree about civil time during the transition. The timekeeping it gives the +# most detail for is postal and telegraph time: here, federal legislation (the +# "Bundesgesetz uber die Erstellung von elektrischen Telegraphen") passed on +# 1851-11-23, and an official implementation notice was published 1853-07-16 +# (Bundesblatt 1853, Bd. II, S. 859). On p 72 Messerli writes that in +# practice since July 1853 Bernese time was used in "all postal and telegraph +# offices in Switzerland from Geneva to St. Gallen and Basel to Chiasso" +# (Google translation). For now, model this transition as occuring on +# 1853-07-16, though it probably occurred at some other date in Zurich, and +# legal civil time probably changed at still some other transition date. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Swiss 1941 1942 - May Mon>=1 1:00 1:00 S Rule Swiss 1941 1942 - Oct Mon>=1 2:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] -Zone Europe/Zurich 0:34:08 - LMT 1855 # See above comment. +Zone Europe/Zurich 0:34:08 - LMT 1853 Jul 16 # See above comment. 0:29:46 - BMT 1894 Jun # Bern Mean Time 1:00 Swiss CE%sT 1981 1:00 EU CE%sT diff --git a/zic.8 b/zic.8 index a2374a1..7ea94c5 100644 --- a/zic.8 +++ b/zic.8 @@ -468,7 +468,7 @@ Rule EU 1996 max - Oct lastSun 1:00u 0 - .sp .ta \w'# Zone\0\0'u +\w'Europe/Zurich\0\0'u +\w'GMTOFF\0\0'u +\w'RULES/SAVE\0\0'u +\w'FORMAT\0\0'u # Zone NAME GMTOFF RULES/SAVE FORMAT UNTIL -Zone Europe/Zurich 0:34:08 - LMT 1855 +Zone Europe/Zurich 0:34:08 - LMT 1853 Jul 16 0:29:46 - BMT 1894 Jun 1:00 Swiss CE%sT 1981 1:00 EU CE%sT @@ -480,9 +480,9 @@ Link Europe/Zurich Switzerland In this example, the zone is named Europe/Zurich but it has an alias as Switzerland. This example says that Zurich was 34 minutes and 8 -seconds west of UT until 1855-01-01 at 00:00, when the legal offset +seconds west of UT until 1853-07-16 at 00:00, when the legal offset was changed to 7\(de\|26\(fm\|22.50\(sd; although this works out to -0:29.45.50, the input format cannot represent fractional seconds so it +0:29:45.50, the input format cannot represent fractional seconds so it is rounded here. After 1894-06-01 at 00:00 Swiss daylight saving rules (defined with lines beginning with "Rule Swiss") apply, and the UT offset became one hour. From 1981 to the present, EU daylight saving rules have -- 1.8.1.2

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Re: [tz] Getting close to new release: testing, testing, ... [SEC=UNOFFICIAL]
by Timothy Arceri Sept. 12, 2013

Sept. 12, 2013

Will you be including the updates to the Australian Daylight Saving's abbreviations in this release? http://mm.icann.org/pipermail/tz/2013-April/019099.html -----Original Message----- From: tz-bounces(a)iana.org [mailto:tz-bounces@iana.org] On Behalf Of Paul Eggert Sent: Wednesday, 11 September 2013 7:55 PM To: Time zone mailing list Subject: [tz] Getting close to new release: testing, testing, ... We need to release a new version soon, because of Fiji. I did further testing and it appears that the recent changes to add meta-information to the zic output won't fly, because they're incompatible with the GNU C library on Ubuntu 12.04. So we need to rethink that feature. There's no rush to introduce it, so let's omit it from the next release. Also, the -t option recently added to tzselect seems like it will be superseded by the tzwinnow approach, whenever we get that working and stable, so for now I think I'd rather omit this. There are a few other problems found by "make public", mostly links that were in the wrong files. I'll post proposed changes soon. If other people could do some testing that'd be nice. You can run "make public". The output should contain the following diagnostics: warning: "antarctica", line 318: Antarctica/Palmer: pre-2013 clients may mishandle distant timestamps warning: "asia", line 1412: 24:00 not handled by pre-1998 versions of zic warning: "asia", line 2332: 24:00 not handled by pre-1998 versions of zic warning: "asia", line 1026: Asia/Jerusalem: pre-2013 clients may mishandle distant timestamps (rule from "asia", line 1021) warning: "asia", line 1315: Asia/Amman: pre-1994 clients may mishandle distant timestamps warning: "asia", line 2016: Asia/Gaza: pre-2013 clients may mishandle distant timestamps warning: "asia", line 2347: Asia/Hebron: pre-2013 clients may mishandle distant timestamps warning: "australasia", line 269: Pacific/Fiji: pre-2013 clients may mishandle distant timestamps warning: "europe", line 998: America/Godthab: pre-2013 clients may mishandle distant timestamps warning: "southamerica", line 1141: America/Santiago: pre-2013 clients may mishandle distant timestamps warning: "southamerica", line 1313: Pacific/Easter: pre-2013 clients may mishandle distant timestamps along with a very long section that starts as follows, which shows that the tz code is still broken on platforms with unsigned 32-bit time_t (this is a longstanding problem). checking uint32_t zones ... --- tzpublic/int64_t.out 2013-09-11 02:43:50.871343089 -0700 +++ tzpublic/uint32_t.out 2013-09-11 02:43:55.907343185 -0700 @@ -210,278 +210,6 @@ Europe/Andorra Sun Mar 29 01:00:00 2037 UT = Sun Mar 29 03:00:00 2037 CEST isdst=1 Europe/Andorra Sun Oct 25 00:59:59 2037 UT = Sun Oct 25 02:59:59 2037 CEST isdst=1 Europe/Andorra Sun Oct 25 01:00:00 2037 UT = Sun Oct 25 02:00:00 2037 CET isdst=0 -Europe/Andorra Sun Mar 28 00:59:59 2038 UT = Sun Mar 28 01:59:59 2038 CET isdst=0 -Europe/Andorra Sun Mar 28 01:00:00 2038 UT = Sun Mar 28 03:00:00 2038 CEST isdst=1 -Europe/Andorra Sun Oct 31 00:59:59 2038 UT = Sun Oct 31 02:59:59 2038 CEST isdst=1

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POSIX extension check
by Arthur David Olson Sept. 10, 2013

Sept. 10, 2013

It's probably worthwhile to check whether extended POSIX in zic-produced binaries will cause grief when those binaries are used with old versions of localtime.c. If so, one or more of documentation, a zic warning, or a version number bump may be in order. --ado

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a patch for zic.c to allow 'follow rules'
by Alois Treindl Sept. 10, 2013

Sept. 10, 2013

Dear Arthur, I have been preparing a small modification for zic.c which will allow it to understand a 'follow rule' in zone files, like this: # experimental table for Geneva, to test the 'follow' mechanism Zone Europe/Geneva 0:24:37 - LMT 1848 Sep 12 0:24:37 - GET 1894 Jun # Geneva MTime 0 follow Europe/Zurich For test purposes, one can simply insert this zone in the europe file. The feature is helpful in the extension of tzdata to cover complete timezone history. For this purpose, about 1000 additional zone files need to be written, and to be maintained. The process to do so has started in the astrological community, as it needs a complete pre-1970 timezone history. I will not bother you with details. I intend to help creating and maintaining a set of files like 'europe_hist', 'asia_hist' etc which contain the additional zones. The 'follow rule' will allow to keep these extra zone files very small, as usually the additional zones will all have a cross-over moment into a regular tzdata zone. I have for the moment called the modified zic source file zicx.c and prepared a patch file for zic.c to implement the 'follow rule' feature. I have tried to keep the modification very small. Please have a look at the patch, and check for the errors I have probably made. Description of the code: ------------------------ The follow rule must be the last line in a zone, and recursion is not allowed. It is parsed in inzsub() which reacts on GMTOFF = 0 and the word 'follow' in the RULE field. The zone line is stored in zones[] with a special value z_gmtoff = FOLLOW_MARK and the zone_name to follow in field z_rule (which is abused for this purpose). Before the call to outzone() the two sets of zone lines are patched together in a temporary array, so that outzone() and all functions deeper down() need not be modified. Patch ----- --- zic.c 2011-03-09 20:41:27.000000000 +0100 +++ zicx.c 2011-08-25 16:09:04.000000000 +0200 @@ -262,6 +262,17 @@ static int typecnt; #define YR_MAXIMUM 1 #define YR_ONLY 2 +/* +** follow rules, added by Alois Treindl August 2011 +** Zones may end with a line: 0 follow zone_name +** which the parser will represent with FOLLOW_MARK in z_gmtoff, +** and the zone name in z_rule. +** Before the call to outzone() the zone and its follow zone will be +** patched together, so that outzone() sees a regular zone array. +** To keep zone files readable, follow rules cannot be used recursively. +*/ +#define FOLLOW_MARK 999999 + static struct rule * rules; static int nrules; /* number of rules */ @@ -589,7 +600,48 @@ _("%s: More than one -L option specified */ for (j = i + 1; j < nzones && zones[j].z_name == NULL; ++j) continue; - outzone(&zones[i], j - i); + if (zones[j -1].z_gmtoff == FOLLOW_MARK) { + /* copy zone and follow zone into one new array */ + int k,n,m, nrows; + struct zone *xzones, *zp; + nrows = j - i - 1; + zp = &zones[j - 1]; /* line with the follow rule */ + xzones = (struct zone *) (void *) emalloc((int) (nrows * sizeof *xzones)); + for (k = 0; k < nrows; k++) + xzones[k] = zones[i + k]; + /* now find the follow zone in array zones[] */ + for (m = 0; m < nzones; m++) { + if (zones[m].z_name != NULL && strcmp(zp->z_rule, zones[m].z_name) == 0) break; + } + if (m == nzones) { /* error, follow zone not found */ + char *cp; + cp = emalloc(80 + strlen(zp->z_rule) + strlen(zones[i].z_name));; + sprintf(cp, "For zone %s follow zone %s not found, no zonefile created.", zones[i].z_name, zp->z_rule); + eat(zp->z_filename, zp->z_linenum); + error(cp); + ifree(cp); + ifree((void *)xzones); + } + /* now find the next date in the follow zone */ + for (n = m + 1; n < nzones; n++) { + if (zp->z_untiltime < zones[n].z_untiltime) break; + } + /* missing errorcode for case n == nzones, + * assume we are still in same follow zone. + * The follow zone part we need starts at zones[n]. + * Now find where follow zone ends, will be m. + */ + for (m = n; m < nzones && zones[m].z_name == NULL; ++m) + continue; + xzones = (struct zone *) (void *) erealloc((char *) xzones, (int) ((nrows + m - n) * sizeof *xzones)); + for (k = 0; k < m - n; k++) + xzones[nrows + k] = zones[n + k]; + nrows += m - n; + outzone(&xzones[0], nrows); + ifree((void *) xzones); + } else { + outzone(&zones[i], j - i); + } } /* ** Make links. @@ -784,7 +836,7 @@ associate(void) } for (i = 0; i < nzones; ++i) { zp = &zones[i]; - if (zp->z_nrules == 0) { + if (zp->z_nrules == 0 && zp->z_gmtoff != FOLLOW_MARK) { /* ** Maybe we have a local standard time offset. */ @@ -1079,11 +1131,23 @@ const int iscont; return FALSE; } } - z.z_rule = ecpyalloc(fields[i_rule]); - z.z_format = ecpyalloc(fields[i_format]); - if (max_format_len < strlen(z.z_format)) - max_format_len = strlen(z.z_format); - hasuntil = nfields > i_untilyear; + /* check for 0 follow zonename + ** zonename must contain at least one /, and follow must be + * 'follow' or an abbreviation thereof. + */ + if (z.z_gmtoff == 0 && strchr(fields[i_format], '/') != NULL + && itsabbr(fields[i_rule], "follow")) { + z.z_gmtoff = FOLLOW_MARK; + z.z_rule = ecpyalloc(fields[i_format]); + z.z_format = ""; + hasuntil = FALSE; /* no continue of zone now */ + } else { + z.z_rule = ecpyalloc(fields[i_rule]); + z.z_format = ecpyalloc(fields[i_format]); + if (max_format_len < strlen(z.z_format)) + max_format_len = strlen(z.z_format); + hasuntil = nfields > i_untilyear; + } if (hasuntil) { z.z_untilrule.r_filename = filename; z.z_untilrule.r_linenum = linenum;

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DESTDIR patch
by Dr. Volker Zell Sept. 10, 2013

Sept. 10, 2013

Hi Attached a patch which adds DESTDIR support to the Makefile. Ciao Volker

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Fiji daylight savings
by David Wheeler Sept. 9, 2013

Sept. 9, 2013

Hi all, we've just received notice that Fiji will start daylight savings shortly, but this doesn't seem to be represented in tzdata. See link below for details. http://www.fiji.gov.fj/Media-Center/Press-Releases/DAYLIGHT-SAVING-STARTS-O… Cheers, -- David _____________________________ David Wheeler - Lead Engineer david(a)inomial.com p +61 3 9663 3554 WINNER 2013 ACOMMS Awards for Services to Industry - Professional services Telecommunications and Utility Billing, Rating, Policy and Session Management

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