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[PATCH 1/2] Switch from RFC 8536 to 9636 for documentation
by Paul Eggert Nov. 3, 2024

Nov. 3, 2024

RFC 9636 is now published, and it obsoletes RFC 8536 for the Time Zone information format (TZif). --- Makefile | 2 +- NEWS | 4 ++++ localtime.c | 2 +- theory.html | 4 ++-- tz-link.html | 4 ++-- tzfile.5 | 12 ++++++------ tzfile.h | 2 +- zic.c | 4 ++-- 8 files changed, 19 insertions(+), 15 deletions(-) diff --git a/Makefile b/Makefile index 57d1d672..6e623eb0 100644 --- a/Makefile +++ b/Makefile @@ -137,7 +137,7 @@ TIME_T_ALTERNATIVES_TAIL = int_least32_t.ck uint_least32_t.ck \ uint_least64_t.ck # What kind of TZif data files to generate. (TZif is the binary time -# zone data format that zic generates; see Internet RFC 8536.) +# zone data format that zic generates; see Internet RFC 9636.) # If you want only POSIX time, with time values interpreted as # seconds since the epoch (not counting leap seconds), use # REDO= posix_only diff --git a/NEWS b/NEWS index adaa4b60..8c315643 100644 --- a/NEWS +++ b/NEWS @@ -24,6 +24,10 @@ Unreleased, experimental changes 1977, and May and July 1990; and removing incorrect transitions in March and September 1978. + Changes to documentation + + Cite Internet RFC 9636, which obsoletes RFC 8536 for TZif format. + Release 2024b - 2024-09-04 12:27:47 -0700 diff --git a/localtime.c b/localtime.c index 7ae9ce5e..f331473e 100644 --- a/localtime.c +++ b/localtime.c @@ -583,7 +583,7 @@ tzloadbody(char const *name, struct state *sp, bool doextend, correction must differ from the previous one's by 1 second or less, except that the first correction can be any value; these requirements are more generous than - RFC 8536, to allow future RFC extensions. */ + RFC 9636, to allow future RFC extensions. */ if (! (i == 0 || (prevcorr < corr ? corr == prevcorr + 1 diff --git a/theory.html b/theory.html index b1717e7d..4d72ee2e 100644 --- a/theory.html +++ b/theory.html @@ -1115,8 +1115,8 @@ However POSIX.1-2024, like earlier POSIX editions, has some limitations: the name of a file from which time-related information is read. The file's format is <dfn><abbr>TZif</abbr></dfn>, a timezone information format that contains binary data; see - <a href="https://datatracker.ietf.org/doc/html/8536">Internet - <abbr>RFC</abbr> 8536</a>. + <a href="https://datatracker.ietf.org/doc/html/9636">Internet + <abbr>RFC</abbr> 9636</a>. The daylight saving time rules to be used for a particular timezone are encoded in the <abbr>TZif</abbr> file; the format of the file allows <abbr>US</abbr>, diff --git a/tz-link.html b/tz-link.html index be2aae54..0853bd7d 100644 --- a/tz-link.html +++ b/tz-link.html @@ -194,9 +194,9 @@ After obtaining the code and data files, see the The code lets you compile the <code><abbr>tz</abbr></code> source files into machine-readable binary files, one for each location. The binary files are in a special format specified by -<a href="https://datatracker.ietf.org/doc/html/8536">The +<a href="https://datatracker.ietf.org/doc/html/9636">The Time Zone Information Format (<abbr>TZif</abbr>)</a> -(Internet <abbr title="Request For Comments">RFC</abbr> 8536). +(Internet <abbr title="Request For Comments">RFC</abbr> 9636). The code also lets you read a <abbr>TZif</abbr> file and interpret timestamps for that location.</p> diff --git a/tzfile.5 b/tzfile.5 index f2529b01..b699bd26 100644 --- a/tzfile.5 +++ b/tzfile.5 @@ -17,7 +17,7 @@ The timezone information files used by .BR tzset (3) are typically found under a directory with a name like .IR /usr/share/zoneinfo . -These files use the format described in Internet RFC 8536. +These files use the format described in Internet RFC 9636. Each file is a sequence of 8-bit bytes. In a file, a binary integer is represented by a sequence of one or more bytes in network order (bigendian, or high-order byte first), @@ -380,7 +380,7 @@ for permanent Atlantic Standard Time (\-04). .IP \(bu Some readers designed for version 2 or 3 and that require strict -conformance to RFC 8536 reject version 4 files whose leap second +conformance to RFC 9636 reject version 4 files whose leap second tables are truncated at the start or end in expiration times. .IP \(bu Some readers ignore the footer, and instead predict future @@ -514,9 +514,9 @@ of one hour, or of 15 minutes, or of 1 minute. .PP Olson A, Eggert P, Murchison K. The Time Zone Information Format (TZif). 2019 Feb. -.UR https://\:datatracker.ietf.org/\:doc/\:html/\:rfc8536 -Internet RFC 8536 +.UR https://\:datatracker.ietf.org/\:doc/\:html/\:rfc9636 +Internet RFC 9636 .UE -.UR https://\:doi.org/\:10.17487/\:RFC8536 -doi:10.17487/RFC8536 +.UR https://\:doi.org/\:10.17487/\:RFC9636 +doi:10.17487/RFC9636 .UE . diff --git a/tzfile.h b/tzfile.h index b1541466..f8c6c8c5 100644 --- a/tzfile.h +++ b/tzfile.h @@ -26,7 +26,7 @@ #endif /* !defined TZDEFRULES */ -/* See Internet RFC 8536 for more details about the following format. */ +/* See Internet RFC 9636 for more details about the following format. */ /* ** Each file begins with. . . diff --git a/zic.c b/zic.c index cf8e79df..6da35270 100644 --- a/zic.c +++ b/zic.c @@ -2761,7 +2761,7 @@ writezone(const char *const name, const char *const string, char version, if (thisleapexpiry) { /* Append a no-op leap correction indicating when the leap second table expires. Although this does not conform to - Internet RFC 8536, most clients seem to accept this and + Internet RFC 9636, most clients seem to accept this and the plan is to amend the RFC to allow this in version 4 TZif files. */ puttzcodepass(leapexpires, fp, pass); @@ -3007,7 +3007,7 @@ stringzone(char *result, struct zone const *zpfirst, ptrdiff_t zonecount) result[0] = '\0'; - /* Internet RFC 8536 section 5.1 says to use an empty TZ string if + /* Internet RFC 9636 section 6.1 says to use an empty TZ string if future timestamps are truncated. */ if (hi_time < max_time) return -1; -- 2.43.0

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Ukraine to abolish DST?
by Steffen Thorsen Oct. 26, 2024

Oct. 26, 2024

Ukraine seems to be getting rid of DST, according to https://universemagazine.com/en/the-verkhovna-rada-canceled-daylight-saving… "During a meeting of the Verkhovna Rada of Ukraine on June 16, daylight saving time was canceled. According to MP Yaroslav Zheleznyak, 261 MPs voted in favor of the bill. Now it must be signed by the President of Ukraine, and then it will come into force." which is again referencing (in Ukrainan) https://lb.ua/society/2024/07/16/624453_verhovna_rada_skasuvala_perehid.html It seems they will plan to set back time this autumn to winter(standard) time, and then stay on that. Best regards, Steffen Thorsen - timeanddate.com

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Brazil may reinstate daylight saving time soonish
by Paul Eggert Oct. 17, 2024

Oct. 17, 2024

A Reuters report[1] says that energy authorities in Brazil have approved a plan to bring back daylight saving time, to save electrical energy during a major drought that has hurt hydroelectric power generation[2]. As far as I know authorities have not decided or published details of the plan, such as which states would be involved and dates and times of transitions. However, one English-language report says that DST would not start until after the election period ends on October 27[3]. This is not a done deal, as any change would need approval by President Luiz Inácio Lula da Silva. That being said, Brazil's DST was abolished by Lula's predecessor and political opponent Jair Bolsonaro, and Lula did an informal Twitter poll shortly after his election in which 66% of respondents voted for DST[4], so presumably Lula would favor restoring DST. [1]: Rodrigo Viga Gaier and Leticia Fucuchima. Brazil energy authorities approve returning to daylight saving time as drought bites. Reuters. 2024-09-20. <https://www.reuters.com/world/americas/brazil-likely-reinstate-daylight-sav…> [2]: Daylight Saving Time Won’t Fix Brazil’s Energy Crisis. Latin American Post. 2024-09-23. <https://latinamericanpost.com/analysis-en/daylight-saving-time-wont-fix-bra…> [3]: Leonardo Vieceli. Brazil's National Electric Operator Recommends Daylight Saving Time. Folha de S.Paulo. 2024-09-20. <https://www1.folha.uol.com.br/internacional/en/business/2024/09/brazils-nat…> [4]: Amanda Audi. Will Brazil bring back daylight saving time? The Brazilian report. 2024-01-02. <https://brazilian.report/society/2024/01/02/lula-daylight-saving-time/>

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[PROPOSED] Port better to glibc when used internally there
by Paul Eggert Oct. 16, 2024

Oct. 16, 2024

I ran into this problem when compiling an experimental version of glibc, which uses tzcode internally. * private.h (static_assert): Override any definition a nonconforming implementation may provide. --- private.h | 1 + 1 file changed, 1 insertion(+) diff --git a/private.h b/private.h index c3304104..4b035ed7 100644 --- a/private.h +++ b/private.h @@ -51,6 +51,7 @@ #endif #if __STDC_VERSION__ < 202311 +# undef static_assert # define static_assert(cond) extern int static_assert_check[(cond) ? 1 : -1] #endif -- 2.43.0

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Winter Time in Palestine for 2024s year
by heba.hamad Oct. 9, 2024

Oct. 9, 2024

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Potential Inconsistency in tz Database (2024b) for Mexico 1931
by Bogdan Hoancea Sept. 16, 2024

Sept. 16, 2024

Dear IANA Team, I hope this message finds you well. My name is Bogdan Hoancea, and I am a software engineer at ABB. We maintain the software package tzdata<https://www.npmjs.com/package/tzdata>, which utilizes the tz database for generating time zone information. I am reaching out regarding a potential inconsistency I noticed in the latest tz database release (tzdata2024b/northamerica). Specifically, for Mexico in 1931, "May 1 23:00" appears to have been changed to "April 30 0:00," whereas it seems the correct adjustment should have been "Apr 30 0:00," in line with the rest of the table. [cid:image001.png@01DB0854.42FCA410] While it is always a possibility to handle this particular case in our software, I wanted to bring it to your attention in case it impacts other users as well, and also, we would prefer it if the root cause of the issue was handled. Thank you for your continued work in maintaining such a critical resource, and please feel free to reach out if any further information is required. Best regards, Bogdan Hoancea [https://signatures.spiritit.com/ABB_Logo_HR.png]<http://www.abb.com/> - Bogdan Hoancea Software engineer - SpiritIT Measurement & Analytics ABB b.v. Achtseweg Zuid 151A / Strijp-TQ Entrance 5 5651GW Eindhoven, The Netherlands Phone: +31 88 440 47 12 abb.com

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Makefile checknow
by Stephen Colebourne Sept. 15, 2024

Sept. 15, 2024

Hi, The Makefile contains a section called `check_now`. It references the files `zone1970.tab` and `zonenow.tab`. Other sections of the Makefile take account of the variable $ZONETABLES before using/checking zone files. Would it be possible to alter Makefile so it only runs check_now if at least one of zone1970/zonenow are in $ZONETABLES ? eg. something like this (now 100% sure this is the right logic...): check_now: checknow.awk date tzdata.zi zdump zic zone1970.tab zonenow.tab for tab in $(ZONETABLES); do \ rm -fr $@.dir mkdir $@.dir ./zic -d $@.dir tzdata.zi now=$(CHECK_NOW_TIMESTAMP) && \ future=`expr $(CHECK_NOW_FUTURE_SECS) + $$now` && \ ./zdump -i -t $$now,$$future \ $$(find $$PWD/$@.dir/????*/ -type f) \ >$@.dir/zdump.tab $(AWK) \ -v zdump_table=$@.dir/zdump.tab \ -f checknow.awk zonenow.tab rm -fr $@.dir done touch $@ thanks Stephen

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Issue with "April" in northamerica file also breaks Elixir tzdata lib updater (":tzdata_release_updater terminating..."), a dependency of timex
by greg＠rumandcode.io Sept. 12, 2024

Sept. 12, 2024

Just wanted to add to the list of libraries impacted by this issue. tzdata is a dependency of the timex library, one of the most popular in the elixir ecosystem. A 2024c release with the fix would be much appreciated. Best regards, Greg McDonald

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Tzdb: Apr-April Issue: Request to provide ETA for next release with the fix - 2024c
by sattisrinivas89＠gmail.com Sept. 10, 2024

Sept. 10, 2024

Greetings Team, I am writing to bring to your attention a critical issue we've encountered with the recent release of https://github.com/eggert/tz -version 2024b. We are using https://github.com/HowardHinnant/date library for our scheduler, the changes with 2024b have caused our schedulers to fail across thousands of agents. Given the scale of our deployment, manually fixing each affected agent is not a feasible solution for us. I see the issue has been fixed in the repo, I really appreciate making a quick fix. Could you please provide an estimated timeline for when we can expect a new release with the fix. If possible, we would greatly appreciate it if you could expedite the release with the fix. Thank you very much for your prompt attention to this matter. We look forward to your response. Thanks Srinivas.

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2024b
by Christopher Burke Sept. 9, 2024

Sept. 9, 2024

Greetings, I am not sure if this is technically an error from your perspective or not; but the latest 2024b DB does not load using the Azul ZUUpdater Tool. It fails with the following message: Failed: java.lang.Exception: Failed while parsing file '/tmp/ziupdater1990610874409301294343524276772419/srcdir/northamerica' on line 2633 'Rule Mexico 1931 only - April 30 0:00 1:00 D' From looking at the source files this is the only occurrence of a full month string I could find; the rest are 3 letter abbreviations, e.g. Apr. I thought I would let you know in case this was a mistake. Regards Chris Burke This message may contain confidential and/or privileged information and is intended solely for the named recipient. Please notify Air New Zealand immediately if received in error and delete the message (do not distribute further). Views expressed are those of the sender and may not represent Air New Zealand. For more information on the Air New Zealand Group, visit us online at https://www.airnewzealand.com/

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