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Update for tz-how-to.html?
by Kerry Shetline May 6, 2018

May 6, 2018

Could we get an update to the tz-how-to.html document which: 1) Explains how to parse tzdata files for vanguard, rearguard, and standard versions? It looks like the way vanguard sections are not commented out, and rearguard sections are, that any third-party parser for tzdata is going to pick up vanguard zones and rules by default, rather than main. What I’d like to know how to parse the tzdata files, directly as they are found in a standard distribution, with rearguard, main, or vanguard results in mind, and without to run "make tarballs” to get a specific version. 2) Demonstrates the usage of the new ’s' and ‘d' suffixes in SAVE columns? Any help with these issues would be much appreciated. -Kerry

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[PROPOSED] Today's North Korea change was at 23:30, not 24:00
by Paul Eggert May 5, 2018

May 5, 2018

* NEWS, asia (Asia/Pyongyang): Implement this. --- NEWS | 5 +++++ asia | 6 +++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/NEWS b/NEWS index 90452b7..79d9d80 100644 --- a/NEWS +++ b/NEWS @@ -2,6 +2,11 @@ News for the tz database Unreleased, experimental changes + Changes to past time stamps + + The 2018-05-05 North Korea 30-minute time zone change took place + at 23:30 the previous day, not at 00:00 that day. + Changes to build procedure New 'make' target 'rearguard_tarballs' to build the rearguard diff --git a/asia b/asia index 3d30864..2e829b8 100644 --- a/asia +++ b/asia @@ -1995,6 +1995,10 @@ Rule ROK 1987 1988 - Oct Sun>=8 3:00 0 S # Assembly, as published in Rodong Sinmun. # From Tim Parenti (2018-04-29): # It appears to be the front page story at the top in the right-most column. +# +# From Paul Eggert (2018-05-04): +# The BBC reported that the transition was from 23:30 to 24:00 today. +# https://www.bbc.com/news/world-asia-44010705 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Seoul 8:27:52 - LMT 1908 Apr 1 @@ -2007,7 +2011,7 @@ Zone Asia/Pyongyang 8:23:00 - LMT 1908 Apr 1 8:30 - KST 1912 Jan 1 9:00 - JST 1945 Aug 24 9:00 - KST 2015 Aug 15 00:00 - 8:30 - KST 2018 May 5 + 8:30 - KST 2018 May 4 23:30 9:00 - KST ############################################################################### -- 2.7.4

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Morocco TZ
by Sebastien WILLEMIJNS May 4, 2018

May 4, 2018

Morocco TZ changes in 8 days... i think the list knew... https://www.africatopsuccess.com/2018/05/03/maroc-changement-dhoraire-dhive… -- --- Sébastien WILLEMIJNS

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Re: [tz] [tz-announce] 2018e release of tz code and data available
by Paul Eggert May 4, 2018

May 4, 2018

On 05/04/2018 07:52 AM, J William Piggott wrote: > On 05/03/2018 08:22 PM, Paul Eggert wrote: > > 8< ... > >> ; effectively the main format now uses vanguard instead of rearguard format. > 8< ... > >> The full effect of this change is only in vanguard format; in rearguard and >> main format, the tm_isdst flag is still zero in winter and nonzero in summer. > ... > > Aren't these to statements contradictory? Yes they are, and that typo wasn't fixed until after the 2018e release was cut. You can see a copy of the fix here: https://mm.icann.org/pipermail/tz/2018-May/026447.html

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[tz-announce] 2018e release of tz code and data available
by Paul Eggert May 4, 2018

May 4, 2018

The 2018e release of the tz code and data is available. It reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Briefly: North Korea switches back to +09 on 2018-05-05. The main format uses negative DST again, for Ireland etc. 'make tarballs' now also builds a rearguard tarball. New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines. Changes to past and future time stamps North Korea switches back from +0830 to +09 on 2018-05-05. (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon, and Tim Parenti.) Bring back the negative-DST changes of 2018a, except be more compatible with data parsers that do not support negative DST. Also, this now affects historical time stamps in Namibia and the former Czechoslovakia, not just Ireland. The main format now uses negative DST to model time stamps in Europe/Dublin (from 1971 on), Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This does not affect UT offsets, only time zone abbreviations and the tm_isdst flag. Also, this does not affect rearguard or vanguard formats; effectively the main format now uses vanguard instead of rearguard format. Data parsers that do not support negative DST can still use data from the rearguard tarball described below. Changes to build procedure The command 'make tarballs' now also builds the tarball tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz except that it uses rearguard format intended for trailing-edge data parsers. Changes to data format and to code The SAVE column of Rule and Zone lines can now have an 's' or 'd' suffix, which specifies whether the adjusted time is standard time or daylight saving time. If no suffix is given, daylight saving time is used if and only if the SAVE column is nonzero; this is the longstanding behavior. Although this new feature is not used in tzdata, it could be used to specify the legal time in Namibia 1994-2017, as opposed to the popular time (see below). Changes to past time stamps From 1994 through 2017 Namibia observed DST in winter, not summer. That is, it used negative DST, as Ireland still does. This change does not affect UTC offsets; it affects only the tm_isdst flag and the abbreviation used during summer, which is now CAT, not WAST. Although (as noted by Michael Deckers) summer and winter time were both simply called "standard time" in Namibian law, in common practice winter time was considered to be DST (as noted by Stephen Colebourne). The full effect of this change is only in vanguard format; in rearguard and main format, the tm_isdst flag is still zero in winter and nonzero in summer. In 1946/7 Czechoslovakia also observed negative DST in winter. The full effect of this change is only in vanguard format; in rearguard and main formats, it is modeled as plain GMT without daylight saving. Also, the dates of some 1944/5 DST transitions in Czechoslovakia have been changed. Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2018e.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2018e.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2018e.tar.lz As usual, links to the latest release files are here: https://www.iana.org/time-zones/repository/tzcode-latest.tar.gz https://www.iana.org/time-zones/repository/tzdata-latest.tar.gz https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz Links are also available via plain HTTP, and via FTP from ftp://ftp.iana.org/tz/releases with the same basenames as above. Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. This release corresponds to commit 4758e88f99c71af65d73ce730e87438466032a5f dated 2018-05-01 23:42:51 -0700 and tagged '2018e' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: 4a245cae2d0922b24539a94cf4a8ccc2bba1ee696e0aaefecb41c7c8d78724a7fcea6039909336177b8b26fec8fc47719e3e56ca9839dbaf52f9a4fec84d4717 tzcode2018e.tar.gz d059fcd381b2f6ecdafcd68fdd2a00451d1bf9b1affeb164ae7cabca2e022d499e77f0706ec3f3091b8e84c2211aa66da6c90937108771f1bf070cfebc105cae tzdata2018e.tar.gz afb7569cc9faef6e3d2be16ceef65f8531ac123dac14e3b40a4f54dab916e930b09eb665458e55f98398c4b8c5d108f34985a42bf711b2170de90d819bf0e630 tzdb-2018e.tar.lz Here are the GPG checksums for the release files: -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9nAAoJEO2X6Q5iqn40r+EQAJSt3ap8G8swYPzBg6TstckZ tOxrDcGlRu4km6jzIhHelOwj2Sxw8X/0JyRc09xbGbXGE/mv35DrzKC8ijfazu9pg Mr4eOclfFGq8l48aRag86hR33k62K84Xdl0WrwVFVefhlsRel9i6lXnBFcmgHl/C vSwJXyrZ2DgvZH88B6j8qnYkw/BMbsTKLM1L/3EHxKZqq/TCHS19Z1XbbkF6mm/u 73aHHmXEnpSVol+3aekEKuS+PSdc+loYaAMvibBJ34ci2bc1X1HkOPF30dRSTETW pVtKXp1qFtmHRR07I28l7/jEzmI+XPheCswhOKowWqKe59tA2CTiFnkhuBQUmoZS XDjKpcgvrad9RSES1aVAfVn2iCx78Inu0W8UIWZ/eiMOh0taQH3n7K1KBnLwCEKd rAB9ummGRK787XJEe2/xnH/h0lilU7Ye6EddNwuGf5Q3PlS9brDov66dnIUWi76L uPRTufummczt6XcA9YL0zEhwvAzjSSqQzoga7mXBKSIwakRoKXCIoux+EdQOWNOy /VUMH5NIkND+kRcRdqTXs93Whu7SCV14DKi5j1LL39YC8nqGi0q3u8wndm22AhCr ZR9uMv1Qq1iCXb09sIBfdi7bf0S8348jz1deb/d7jgJ4ISBR7v8UiR3Z/JO8hiPR QSP93j37rjAsFyBSWMxq =knlj -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9nAAoJEO2X6Q5iqn40qYUQAI21DF4x+Qr9uhMf5UL3u/UI BnLTeDqc4t1oLbuuJsbtgausc/m6EIgo2j9+uadXefnguP4fwKHJ2doReuRZ3njI hGnqP2+yCfTRNrZYBU3p6U+/OJq8r/UBsn9aGxNStcZHe6FswnxXWlzpRNbPdNBC nGeYMs2HOQjcdG08BF1sjGm4FC/NS6bugNhs0EcrMLaVa+c0keRWNg9o7Y/SvrZB awFAMz4LhOog2qxhGWtFgSVRAAj5aEDqugOXZL27VszgGPexiAaMCFyQARIHigIw 959D7RYmpeNuEeP6XbzGFgDO6aMbxahoUpP9cCOUI6qKShtDKnY2XkjPmVQiAfjZ zvpsE1dYbWyVTWqWhWL3z0lPCFN6B4eneY6UXY/KtENRl1jEafKN5/7JqKOMBSRo umE1Jy6qSSz5jLuz5pX59iOXWZETIlwtAW6lKe2s6l9xWPL9R8xXoPvbQRadqDxB uANcGZSrKD1jKuybPJa/6BZRF+FlldCkZVVKSSdXuPLF1HhohlvFZqi1WPmWvGd+ s/1+3OhWzB4BHyrp3Wbtj+ZwCtg9UVbJLBM2bgL9nGEyv/1XSxgLJEp3rneIMpJv AMK8rr3XehXLDkXAfx68Mzs3F4lYEdXk6y9f9ZsVj+IdBotwzzjJWeCfnlmJM52y 8cCrPGUjdneFidV9OZ+J =4LFO -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9pAAoJEO2X6Q5iqn40EBwP/1fxMc1IozcXCWSm+h/XZ3M+ bImmIdf8Ws/FZC5yXHWkU4n3DZN6A2Xf/dDTDaZPeyhL3rjd6ju0zxTsQpxdqRms FrEiqlq2CpIVe+pY4EeowfsFdKVYIxtiTw9BNytaDOIgYxRmokNUQusaHw2qrZg6 t6giUhH6bh1/YgZakFP65WItjESR8Dg4aJ7X1f8BJkSEyy9I2lnyWOG7LwB8xNvS YRPRjkVqdVXzdS9MtqO+U5b9pe1MvU6q0lRAOwUvZsGfB7fULkdQcS1XaYDVRdPA WdMKqn21S+oRHYzX5/BZHE68uGFlufPohikYfSCO6pk8eqDe0xbkOl6fpgjjqTZf wCAcZBBoCP11lH8Omdu8bW6LJ0q1jkwuCZxmLBPwonInoByPO/TeDstYSp39KCv2 +w0pl87uYe6/IEwSC1bH0HBF8kzcEq5q5JVHLyqwOKrAm6Nfm5sC5vWFhk3GmMGU FGpFLnwUJlTefy9X3ds8zEvmCAiFMisu5cciMRwfCLvTHSObRGEXtp5pxpr0VhBf A6Qc+83JPTwhEWdVQMVbEWRkkJNG50xAwOhjJaClXjjlvJqQtpUPHLR7fRaQWvm8 sCXhh+PeWpgIbbzaE7TzkVu9sLUGiIvbLiP2yNMOuoZp+UUnrsSaswbeCl0bkGe3 LSswAxioa5rs8zd8WtZe =/AeX -----END PGP SIGNATURE----- PS. If your tzdata parser does not yet support negative DST offsets,this particular release's data entries are also available in arearguard-format tarball and signature that does not contain suchoffsets. This is intended to be a temporary transition aid for theseparsers. The URLs are: https://web.cs.ucla.edu/~eggert/tz/release/2018e/tzdata2018e-rearguard.tar.… https://web.cs.ucla.edu/~eggert/tz/release/2018e/tzdata2018e-rearguard.tar.… with the following SHA-512 and GPG checksums: dd92cf2d01388d52731db7569360e3c7e673c3189c8cba807d031fb6b6ce8c115d3f4de3be1c7a6b1e038fa919efdd254cdd4f7731c3130b447dee2c7c5814a4 tzdata2018e-rearguard.tar.gz -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJa6V9oAAoJEO2X6Q5iqn40jJMP+gKGNy3VBhJ9B2/plNXta2nH M5fAwJphPXutCv2ums0LPVNbi0FWjPo9T2/6Lmy71vyyusW/9ltS+/bECSnmrZRO VEql2UWghxGMaV3Y2wpFI2XGqepQYsT9Xa1tgXUvXHakQPYe5Osx0J3P50F9ROMy kiWR4VSsSE3IZDiZC32HQjcHsREcUtpgYfn943Zr1Go2FRnp2esnbN0eQtTV5vJW uSYWdfSNWNsSqXR9O2cq9kzCeVKxZjjs2hi1adIrQLzQKy26RXUC9f4tepzRrPfT euHiHUrZXE5p2161Q702P1Nw3zPFrA/SHiFZTpP84mri60RVZTWPP21ityktFukt B+Ebkpd7EwyyFFZB1grbnb1uLc2qkM76gKtIPJAtkWEe7BwwwREh9d/92K/L9XTe opehULRUjX65UyOWNUD9dl3aiy1FHQyWAuX3fRF1u2vrh3WSuIHbO0Uq9RCMQtHP VSY45Ldwv3+PGfyaKlQvftqFAFJ2kjmIC7zQZe5HmBIYG8TIyUCS/P17XZzIrEpw aBNrPe4hV63DSVEvBYLHaCPMMIASASBvSZ2S5Rb2HopAzVd6xOYSvGCqwjdtFpr6 1bD4EeIb2wBxPWH8KFZiSDYK/FpfhuZR7teY6bzG+fsZMtzChP4pcQrebMD3RIPZ RBDXrhtfn+5b78wn6VMM =VPo7 -----END PGP SIGNATURE----- _______________________________________________ tz-announce mailing list tz-announce(a)iana.org https://mm.icann.org/mailman/listinfo/tz-announce

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Pyongyang Time transition plan announced
by Seo Sanghyeon May 3, 2018

May 3, 2018

Rodong Sinmun 2018-04-30 announced Pyongyang Time transition plan. https://www.nknews.org/kcna/wp-content/uploads/sites/5/2018/04/rodong-2018-… I won't translate, but even if you don't know Korean it should be easy to confirm that the transition date is 2018-05-05. 2018 is Juche 107. Citation should be Decree No. 2232 of April 30, 2018, of the Presidum of the Supreme People's Assembly, as published in Rodong Sinmun. -- Seo Sanghyeon

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[PROPOSED] Fix typos in 2018e historical NEWS
by Paul Eggert May 3, 2018

May 3, 2018

* NEWS: Fix typos in description of 2018e’s changes to historical timestamps in Namibia and Czechoslovakia. --- NEWS | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/NEWS b/NEWS index e985ce6..90452b7 100644 --- a/NEWS +++ b/NEWS @@ -64,12 +64,12 @@ Release 2018e - 2018-05-01 23:42:51 -0700 both simply called "standard time" in Namibian law, in common practice winter time was considered to be DST (as noted by Stephen Colebourne). The full effect of this change is only in vanguard - format; in rearguard and main format, the tm_isdst flag is still + and main format; in rearguard format, the tm_isdst flag is still zero in winter and nonzero in summer. In 1946/7 Czechoslovakia also observed negative DST in winter. - The full effect of this change is only in vanguard format; in - rearguard and main formats, it is modeled as plain GMT without + The full effect of this change is only in vanguard and main + formats; in rearguard format, it is modeled as plain GMT without daylight saving. Also, the dates of some 1944/5 DST transitions in Czechoslovakia have been changed. -- 2.17.0

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[PROPOSED] Port better to GCC 8
by Paul Eggert May 1, 2018

May 1, 2018

* private.h (ATTRIBUTE_MALLOC): New macro. Use this and related macros starting with GCC 3.0, not GCC 2.96 which was not an official release. * zdump.c (xmalloc): * zic.c (emalloc, ecpyalloc): Use it to pacify -Wsuggest-attribute=malloc with GCC 8. --- private.h | 4 +++- zdump.c | 2 +- zic.c | 4 ++-- 3 files changed, 6 insertions(+), 4 deletions(-) diff --git a/private.h b/private.h index 705544e..641f905 100644 --- a/private.h +++ b/private.h @@ -342,12 +342,14 @@ typedef unsigned long uintmax_t; #define SIZE_MAX ((size_t) -1) #endif -#if 2 < __GNUC__ + (96 <= __GNUC_MINOR__) +#if 3 <= __GNUC__ # define ATTRIBUTE_CONST __attribute__ ((const)) +# define ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) # define ATTRIBUTE_PURE __attribute__ ((__pure__)) # define ATTRIBUTE_FORMAT(spec) __attribute__ ((__format__ spec)) #else # define ATTRIBUTE_CONST /* empty */ +# define ATTRIBUTE_MALLOC /* empty */ # define ATTRIBUTE_PURE /* empty */ # define ATTRIBUTE_FORMAT(spec) /* empty */ #endif diff --git a/zdump.c b/zdump.c index 1081648..a4d9108 100644 --- a/zdump.c +++ b/zdump.c @@ -136,7 +136,7 @@ sumsize(size_t a, size_t b) /* Return a pointer to a newly allocated buffer of size SIZE, exiting on failure. SIZE should be nonzero. */ -static void * +static void * ATTRIBUTE_MALLOC xmalloc(size_t size) { void *p = malloc(size); diff --git a/zic.c b/zic.c index 90ae1f4..31f1092 100644 --- a/zic.c +++ b/zic.c @@ -447,7 +447,7 @@ memcheck(void *ptr) return ptr; } -static void * +static void * ATTRIBUTE_MALLOC emalloc(size_t size) { return memcheck(malloc(size)); @@ -459,7 +459,7 @@ erealloc(void *ptr, size_t size) return memcheck(realloc(ptr, size)); } -static char * +static char * ATTRIBUTE_MALLOC ecpyalloc (char const *str) { return memcheck(strdup(str)); -- 2.17.0

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[PROPOSED] Use GCC 8 for debugging
by Paul Eggert April 30, 2018

April 30, 2018

* Makefile (GCC_DEBUG_FLAGS): Use flags appropriate for GCC 8. --- Makefile | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/Makefile b/Makefile index 3ac1a67..21fa488 100644 --- a/Makefile +++ b/Makefile @@ -236,14 +236,16 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ $(GCC_INSTRUMENT) \ -Wall -Wextra \ -Walloc-size-larger-than=100000 -Warray-bounds=2 \ - -Wbad-function-cast -Wcast-align -Wdate-time \ + -Wbad-function-cast -Wcast-align=strict -Wdate-time \ -Wdeclaration-after-statement -Wdouble-promotion \ -Wformat=2 -Wformat-overflow=2 -Wformat-signedness -Wformat-truncation \ -Winit-self -Wjump-misses-init -Wlogical-op \ -Wmissing-declarations -Wmissing-prototypes -Wnested-externs \ -Wold-style-definition -Woverlength-strings -Wpointer-arith \ - -Wshadow -Wshift-overflow=2 -Wstrict-prototypes -Wstringop-overflow=5 \ + -Wshadow -Wshift-overflow=2 -Wstrict-prototypes -Wstringop-overflow=4 \ + -Wstringop-truncation -Wsuggest-attribute=cold \ -Wsuggest-attribute=const -Wsuggest-attribute=format \ + -Wsuggest-attribute=malloc \ -Wsuggest-attribute=noreturn -Wsuggest-attribute=pure \ -Wtrampolines -Wundef -Wuninitialized -Wunused \ -Wvariadic-macros -Wvla -Wwrite-strings \ -- 2.17.0

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DPRK to revert to UTC+9 from UTC+8:30
by Kang Seonghoon April 30, 2018

April 30, 2018

On 2018-04-29 (+09:00), according to Yoon Young-chan, senior presidental secretary for public relations of South Korea, has announced that North Korea will revert its time zone from UTC+8:30 (PYT; Pyongyang Time) back to UTC+9 (KST; Korea Standard Time), in lieu of the recent Panmunjom Declaration. Yet another time to change tzdata? Source: South and North agreed to unify PYT to KST, Yonhap News http://m.yna.co.kr/kr/contents/?cid=AKR20180429018500001 (no English translation exists right now) -- -- Kang Seonghoon | https://mearie.org/ -- Opinions expressed in this email do not necessarily represent the views of my employer. --

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North Korea timezone to become GMT+9 from May 5 2018
by Phake Nick April 30, 2018

April 30, 2018

The URL to the announcement cannot be directly copied, but you can access www.kcna.kp then select "English" on top right hand corner, and then there will be an article titled "SPA Presidium of DPRK Decides to Reset Pyongyang Time" which talk about the upcoming change in time in North Korea. Media outside North Korea have reported about it too. However, there are no info with respect to exactly which moment in May 5 are they switching their timezone

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North Korea to match South Korea's time zone
by Arthur David Olson April 29, 2018

April 29, 2018

A tweet from Jef Poskanzer... https://twitter.com/jef_poskanzer/status/990430801903865856 ...alerted me to North Korea's plan to match South Korea's time zone. An AP item on the matter... https://apnews.com/301adfec088647c1b1cbc69eb4b0949a ...cites South Korean President Moon Jae-in's spokesperson Yoon Young-chan; referring to North Korean leader Kim Jong Un, " Yoon said Kim...revealed plans to re-adjust its current time zone to match the South’s." No word in the AP item on specifics of the plan. @dashdashado

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[PROPOSED] Support zi parsers that mishandle negative DST offsets
by Paul Eggert April 23, 2018

April 23, 2018

This is intended to provide a way to support both clients that require data to have only positive DST offsets, and clients that do not have this restriction. * Makefile (XDST, SDST): New macros. (TZDATA_ZI_DEPS): Add zidst.awk. (DSTDATA_ZI_DEPS): New macro. (all): Depend on fulldata.zi and pdstdata.zi. (fulldata.zi pdstdata.zi): New rule. (tzdata.zi): Use $(XDST)data.zi instead of reading original source. (check_zishrink): Check zidst.awk, too. (clean): Remove all *.zi files, not just tzdata.zi. * NEWS, europe: Mention this. * zidst.awk: New file. --- Makefile | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++----------- NEWS | 30 ++++++++++++++++++++++++++++++ europe | 39 ++++++++++++++++++++++----------------- zidst.awk | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 154 insertions(+), 28 deletions(-) create mode 100644 zidst.awk diff --git a/Makefile b/Makefile index 8c84cd9..92ddb80 100644 --- a/Makefile +++ b/Makefile @@ -10,6 +10,26 @@ VERSION= unknown # Email address for bug reports. BUGEMAIL= tz(a)iana.org +# To install the full data, which can contain daylight saving time +# offsets that are negative (relative to standard time), use +# XDST= full +# To install data containing only positive daylight saving time +# offsets, but otherwise as close to the full data as practical, use +# XDST= pdst +XDST= pdst +# Parsers requiring DST offsets to be positive should use the file +# pdstdata.zi, which contains almost all the data of 'africa' etc., +# except with positive DST offsets. This works around a problem that +# was discovered in January 2018 with negative DST in tests for ICU +# and OpenJDK. See: +# https://mm.icann.org/pipermail/tz/2018-January/025825.html +# https://mm.icann.org/pipermail/tz/2018-January/025822.html +# Currently the 'africa' etc. files use pdst form if comments are +# ignored, to ease transition for parsers that do not support +# negative DST offsets. This is intended to change to full form at +# some point, so that full-featured zi parsers that use the 'africa' +# files will get the full data without changing anything. + # Change the line below for your time zone (after finding the zone you want in # the time zone files, or adding it to a time zone file). # Alternately, if you discover you've got the wrong time zone, you can just @@ -463,7 +483,8 @@ TDATA= $(YDATA) $(NDATA) $(BACKWARD) ZONETABLES= zone1970.tab zone.tab TABDATA= iso3166.tab $(TZDATA_TEXT) $(ZONETABLES) LEAP_DEPS= leapseconds.awk leap-seconds.list -TZDATA_ZI_DEPS= zishrink.awk version $(TDATA) $(PACKRATDATA) +TZDATA_ZI_DEPS= zidst.awk zishrink.awk version $(TDATA) $(PACKRATDATA) +DSTDATA_ZI_DEPS= zidst.awk $(TDATA) $(PACKRATDATA) DATA= $(TDATA_TO_CHECK) backzone iso3166.tab leap-seconds.list \ leapseconds yearistype.sh $(ZONETABLES) AWK_SCRIPTS= checklinks.awk checktab.awk leapseconds.awk zishrink.awk @@ -500,7 +521,8 @@ VERSION_DEPS= \ SHELL= /bin/sh -all: tzselect yearistype zic zdump libtz.a $(TABDATA) +all: tzselect yearistype zic zdump libtz.a $(TABDATA) \ + fulldata.zi pdstdata.zi ALL: all date $(ENCHILADA) @@ -535,11 +557,15 @@ version: $(VERSION_DEPS) printf '%s\n' "$$V" >$@.out mv $@.out $@ -# This file can be tailored by setting BACKWARD, PACKRATDATA, etc. -tzdata.zi: $(TZDATA_ZI_DEPS) +# These files can be tailored by setting BACKWARD, PACKRATDATA, etc. +fulldata.zi pdstdata.zi: $(DSTDATA_ZI_DEPS) + $(AWK) -v outfile='$@' -f zidst.awk $(TDATA) $(PACKRATDATA) \ + >$@.out + mv $@.out $@ +tzdata.zi: $(XDST)data.zi version version=`sed 1q version` && \ LC_ALL=C $(AWK) -v version="$$version" -f zishrink.awk \ - $(TDATA) $(PACKRATDATA) >$@.out + $(XDST)data.zi >$@.out mv $@.out $@ version.h: version @@ -721,17 +747,32 @@ check_tzs: $(TZS) $(TZS_NEW) check_web: tz-how-to.html $(VALIDATE_ENV) $(VALIDATE) $(VALIDATE_FLAGS) tz-how-to.html -# Check that tzdata.zi generates the same binary data that its sources do. -check_zishrink: tzdata.zi zic leapseconds $(PACKRATDATA) $(TDATA) +# The format of the source files, either full or pdst. +# Currently they are in pdst format, but this is expected to change. +SDST = pdst + +# Check that zishrink.awk does not alter the data, and that zidst.awk +# preserves $(SDST) data. +check_zishrink: zic leapseconds $(PACKRATDATA) $(TDATA) \ + $(XDST)data.zi tzdata.zi for type in posix right; do \ - mkdir -p time_t.dir/$$type time_t.dir/$$type-shrunk && \ + mkdir -p time_t.dir/$$type time_t.dir/$$type-$(SDST) \ + time_t.dir/$$type-shrunk && \ case $$type in \ right) leap='-L leapseconds';; \ *) leap=;; \ esac && \ - $(ZIC) $$leap -d time_t.dir/$$type $(TDATA) && \ - $(AWK) '/^Rule/' $(TDATA) | \ + $(ZIC) $$leap -d time_t.dir/$$type $(XDST)data.zi && \ + $(AWK) '/^Rule/' $(XDST)data.zi | \ $(ZIC) $$leap -d time_t.dir/$$type - $(PACKRATDATA) && \ + case $(XDST) in \ + $(SDST)) \ + $(ZIC) $$leap -d time_t.dir/$$type-$(SDST) $(TDATA) && \ + $(AWK) '/^Rule/' $(TDATA) | \ + $(ZIC) $$leap -d time_t.dir/$$type-$(SDST) \ + $(XDST)data.zi && \ + diff -r time_t.dir/$$type time_t.dir/$$type-$(SDST);; \ + esac && \ $(ZIC) $$leap -d time_t.dir/$$type-shrunk tzdata.zi && \ diff -r time_t.dir/$$type time_t.dir/$$type-shrunk || exit; \ done @@ -741,7 +782,7 @@ clean_misc: rm -f core *.o *.out \ date tzselect version.h zdump zic yearistype libtz.a clean: clean_misc - rm -fr *.dir tzdata.zi tzdb-*/ $(TZS_NEW) + rm -fr *.dir *.zi tzdb-*/ $(TZS_NEW) maintainer-clean: clean @echo 'This command is intended for maintainers to use; it' diff --git a/NEWS b/NEWS index 4f763c0..c455f3c 100644 --- a/NEWS +++ b/NEWS @@ -2,6 +2,36 @@ News for the tz database Unreleased, experimental changes + Briefly: + Support zi parsers that mishandle negative DST offsets + + Changes to build procedure + + The new XDST macro in the Makefile lets the installer choose + XDST=full, which allows arbitrary DST offsets in the data, or + XDST=pdst, which allows only positive DST offsets. Choosing + XDST=full is arguably more correct for Ireland, which observes + Irish Standard Time (IST, UTC+01) in summer and GMT (UTC) in + winter. Choosing XDST=pdst is better for zoneinfo parsers that do + not work well with negative DST offsets, notably OpenJDK+CLDR. + On platforms using tzcode or similar APIs, XDST should not affect + any behavior other than that depending on the tm_isdst flag. + + For now this change does not affect client-visible behavior by + default, as the Makefile defaults to XDST=pdst and uncommented + parts of the data source files contain only pdst-format data. + After a bit of time for testing, XDST=full and full-format source + files are planned to become the default, so that parsers that + support negative DST offsets can get full data without changing + their build procedures. Parsers requiring positive DST offsets + should use the new file pdstdata.zi instead of tzdata.zi or the + source files 'africa' etc.: pdstdata.zi is pdst-compatible, it is + automatically built from the data source files, and it will + continue to be pdst-compatible regardless of XDST. To get + full-format data now, use the new file fulldata.zi, which will + continue to be full-format regardless of XDST. To get the format + selected by XDST, use tzdata.zi. + Changes to code The code is a bit more portable to MS-Windows. (Thanks to Manuela diff --git a/europe b/europe index 6c1ccbe..5aeda33 100644 --- a/europe +++ b/europe @@ -508,11 +508,27 @@ Link Europe/London Europe/Jersey Link Europe/London Europe/Guernsey Link Europe/London Europe/Isle_of_Man -# From Paul Eggert (2018-01-19): +# From Paul Eggert (2018-01-30): +# In January 2018 we discovered that the negative DST offsets in the +# Eire rules cause problems with tests for ICU: +# https://mm.icann.org/pipermail/tz/2018-January/025825.html +# and with tests for OpenJDK: +# https://mm.icann.org/pipermail/tz/2018-January/025822.html +# To work around this problem, zidst.awk translates the following data +# lines into two forms. First, fulldata.zi contains the full data, +# which includes negative DST offsets. Second, pdstdata.zi uses a +# traditional approximation for Irish time stamps after 1971-10-31 +# 02:00 UTC; although this approximation has tm_isdst flags that are +# the reverse of the full data, its UTC offsets are correct and this +# suffices for ICU and OpenJDK. Although this source file currently +# has pdstdata.zi lines active and fulldata.zi lines commented out, +# this is intended to change in the near future and downstream code +# should not rely on it. +# # The following is like GB-Eire and EU, except with standard time in # summer and negative daylight saving time in winter. -# Although currently commented out, this will need to become uncommented -# once the ICU/OpenJDK workaround is removed; see below. +# This rule set is active in fulldata.zi and is commented out in +# pdstdata.zi. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S #Rule Eire 1971 only - Oct 31 2:00u -1:00 GMT #Rule Eire 1972 1980 - Mar Sun>=16 2:00u 0 IST @@ -533,24 +549,13 @@ Zone Europe/Dublin -0:25:00 - LMT 1880 Aug 2 0:00 1:00 IST 1947 Nov 2 2:00s 0:00 - GMT 1948 Apr 18 2:00s 0:00 GB-Eire GMT/IST 1968 Oct 27 -# From Paul Eggert (2018-01-18): -# The next line should look like this: +# The next line is active in fulldata.zi and commented out in pdstdata.zi. # 1:00 Eire IST/GMT -# However, in January 2018 we discovered that the Eire rules cause -# problems with tests for ICU: -# https://mm.icann.org/pipermail/tz/2018-January/025825.html -# and with tests for OpenJDK: -# https://mm.icann.org/pipermail/tz/2018-January/025822.html -# To work around this problem, use a traditional approximation for -# time stamps after 1971-10-31 02:00 UTC, to give ICU and OpenJDK -# developers breathing room to fix bugs. This approximation has -# correct UTC offsets, but results in tm_isdst flags are the reverse -# of what they should be. This workaround is temporary and should be -# removed reasonably soon. +# These three lines are active in pdstdata.zi and commented out in +# fulldata.zi. 1:00 - IST 1971 Oct 31 2:00u 0:00 GB-Eire GMT/IST 1996 0:00 EU GMT/IST -# End of workaround for ICU and OpenJDK bugs. ############################################################################### diff --git a/zidst.awk b/zidst.awk new file mode 100644 index 0000000..7885e9a --- /dev/null +++ b/zidst.awk @@ -0,0 +1,50 @@ +# Convert tzdata source into full or positive-DST form + +# Contributed by Paul Eggert. This file is in the public domain. + +# This is not a general-purpose converter; it is designed for current tzdata. +# +# When converting to full form, the output can use negative DST offsets. +# +# When converting to positive-DST form, the output uses only positive +# DST offsets. The idea is for the output data to simulate the +# behavior of the input data as best it can within the constraints of +# positive DST offsets. +# +# In the input, lines requiring the full format are commented #[full] +# and the positive DST near-equivalents are commented #[pdst]. + +BEGIN { + dst_type["full"] = 1 + dst_type["pdst"] = 1 + + # The command line should set OUTFILE to the name of the output file, + # which should start with either "full" or "pdst". + todst = substr(outfile, 1, 4) + if (!dst_type[todst]) exit 1 +} + +/^Zone/ { zone = $2 } + +{ + in_comment = /^#/ + + # Test whether this line should differ between the full and the pdst versions. + Rule_Eire = /^#?Rule[\t ]+Eire[\t ]/ + Zone_Dublin_post_1968 \ + = (zone == "Europe/Dublin" && /^#?[\t ]+[01]:00[\t ]/ \ + && (!$(in_comment + 4) || 1968 < $(in_comment + 4))) + + # If so, uncomment the desired version and comment out the undesired one. + if (Rule_Eire || Zone_Dublin_post_1968) { + if ((Rule_Eire \ + || (Zone_Dublin_post_1968 && $(in_comment + 3) == "IST/GMT")) \ + == (todst == "full")) { + sub(/^#/, "") + } else if (/^[^#]/) { + sub(/^/, "#") + } + } +} + +{ print } -- 2.14.3

7 14

[PATCH] Fix ziguard.awk Namibia invalid assumption
by Paul Eggert April 22, 2018

April 22, 2018

* ziguard.awk: Don’t assume input is in rearguard format. --- ziguard.awk | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/ziguard.awk b/ziguard.awk index 7cdceab..dbe64d6 100644 --- a/ziguard.awk +++ b/ziguard.awk @@ -63,7 +63,11 @@ outfile != "main.zi" { || (1994 <= $(in_comment + 4) && $(in_comment + 4) <= 2017) \ || in_comment + 3 == NF)) if (Rule_Namibia || Zone_using_Namibia_rule) { - if (in_comment == vanguard) { + if ((Rule_Namibia \ + ? ($(in_comment + 9) ~ /^-/ \ + || ($(in_comment + 9) == 0 && $(in_comment + 10) == "CAT")) \ + : $(in_comment + 1) == "2:00" && $(in_comment + 2) == "Namibia") \ + == vanguard) { uncomment = in_comment } else { comment_out = !in_comment -- 2.14.3

1 0

[PROPOSED] Update and/or clean up POSIX version info
by Paul Eggert April 15, 2018

April 15, 2018

--- asctime.c | 12 +++--------- localtime.c | 7 +++---- theory.html | 2 +- 3 files changed, 7 insertions(+), 14 deletions(-) diff --git a/asctime.c b/asctime.c index a55f785..56c54b3 100644 --- a/asctime.c +++ b/asctime.c @@ -1,3 +1,5 @@ +/* asctime and asctime_r a la POSIX and ISO C, except pad years before 1000. */ + /* ** This file is in the public domain, so clarified as of ** 1996-06-05 by Arthur David Olson. @@ -29,7 +31,7 @@ ** leading zeroes to get the newline in the traditional place. ** The -4 ensures that we get four characters of output even if ** we call a strftime variant that produces fewer characters for some years. -** The ISO C 1999 and POSIX 1003.1-2004 standards prohibit padding the year, +** The ISO C and POSIX standards prohibit padding the year, ** but many implementations pad anyway; most likely the standards are buggy. */ #ifdef __GNUC__ @@ -64,10 +66,6 @@ static char buf_asctime[MAX_ASCTIME_BUF_SIZE]; -/* -** A la ISO/IEC 9945-1, ANSI/IEEE Std 1003.1, 2004 Edition. -*/ - char * asctime_r(register const struct tm *timeptr, char *buf) { @@ -117,10 +115,6 @@ asctime_r(register const struct tm *timeptr, char *buf) } } -/* -** A la ISO/IEC 9945-1, ANSI/IEEE Std 1003.1, 2004 Edition. -*/ - char * asctime(register const struct tm *timeptr) { diff --git a/localtime.c b/localtime.c index b6b82bb..5b5a5b1 100644 --- a/localtime.c +++ b/localtime.c @@ -88,9 +88,8 @@ static const char gmt[] = "GMT"; /* ** The DST rules to use if TZ has no rules and we can't load TZDEFRULES. ** Default to US rules as of 2017-05-07. -** POSIX 1003.1 section 8.1.1 says that the default DST rules are -** implementation dependent; for historical reasons, US rules are a -** common default. +** POSIX does not specify the default DST rules; +** for historical reasons, US rules are a common default. */ #ifndef TZDEFRULESTRING #define TZDEFRULESTRING ",M3.2.0,M11.1.0" @@ -2211,7 +2210,7 @@ timeoff(struct tm *tmp, long offset) #ifdef STD_INSPIRED /* -** IEEE Std 1003.1-1988 (POSIX) legislates that 536457599 +** IEEE Std 1003.1 (POSIX) says that 536457599 ** shall correspond to "Wed Dec 31 23:59:59 UTC 1986", which ** is not the case if we are accounting for leap seconds. ** So, we provide the following conversion routines for use diff --git a/theory.html b/theory.html index b27b212..fc2102b 100644 --- a/theory.html +++ b/theory.html @@ -68,7 +68,7 @@ standard for <a href="https://en.wikipedia.org/wiki/Unix">UNIX</a>-like systems. As of this writing, the current edition of POSIX is: <a href="http://pubs.opengroup.org/onlinepubs/9699919799/"> The Open -Group Base Specifications Issue 7</a>, IEEE Std 1003.1-2008, 2016 +Group Base Specifications Issue 7</a>, IEEE Std 1003.1-2017, 2018 Edition. Because the database's scope encompasses real-world changes to civil timekeeping, its model for describing time is more complex than the -- 2.7.4

1 0

[PROPOSED] * europe: Adjust to kalendar.beda.cz correction.
by Paul Eggert April 15, 2018

April 15, 2018

--- europe | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/europe b/europe index 160be9f..6b97fd0 100644 --- a/europe +++ b/europe @@ -971,14 +971,9 @@ Zone Europe/Sofia 1:33:16 - LMT 1880 # Czech Republic / Czechia # -# From Paul Eggert (2018-04-14): -# The source for Czech data is: Kdy začíná a končí letní čas. +# From Paul Eggert (2018-04-15): +# The source for Czech data is: Kdy začíná a končí letní čas. 2018-04-15. # https://kalendar.beda.cz/kdy-zacina-a-konci-letni-cas -# with one correction, taken from: -# Sbírka zákonů a nařízení republiky Československé, částka 92/1946. -# http://ftp.aspi.cz/opispdf/1946/092-1946.pdf -# which says that the winter time (negative DST) starting 1946-12-01 -# was a switch from 03:00 to 02:00 (not from 02:00 to 01:00). # We know of no English-language name for historical Czech winter time; # abbreviate it as "GMT", as it happened to be GMT. # -- 2.14.3

1 0

start of 1946 winter time in "Kdy začíná a končí letní čas"
by Paul Eggert April 14, 2018

April 14, 2018

I recently proposed some tz database changes for Prague; see <https://en.wikipedia.org/wiki/Tz_database> and <https://mm.icann.org/pipermail/tz/2018-April/026415.html>. I used your web page <https://kalendar.beda.cz/kdy-zacina-a-konci-letni-cas> as the main source for these fixes; thank you! I noticed what appears to be a typographical error in your web page. It says: 1946-7 zimní čas 1. prosinec (2:00) 23. únor (2:00) However, the primary source <http://ftp.aspi.cz/opispdf/1946/092-1946.pdf> says: "§1. Počátek zimního času v roce 1946 se určuje na den 1. prosince 1946 o třetí hodiné ranní středoevropského času a provede se posunutím hodinových ručiček na druhou hodinu." Google Translate suggests this means the transition was December 1 at 03:00, not December 1 at 02:00. That is, the clock was 03:00 before the transition, and 02:00 afterwards. The attached patch contains a proposed fix to kalendar.beda.cz. I am CC:ing this to the time zone mailing list to give them a heads-up as to why I made this change in the tz database.

1 0

[PROPOSED 1/2] Czechs had negative DST in 1946/7
by Paul Eggert April 14, 2018

April 14, 2018

* NEWS: Document this. * europe (Czech): Adjust 1945 transition dates to match new source. (Europe/Prague): Likewise. Add negative DST in 1946/7. * tz-link.html: Link to kalendar.beda.cz. * ziguard.awk: Adjust to Czech changes. --- NEWS | 6 ++++++ europe | 24 +++++++++++++++++++++--- tz-link.html | 4 ++++ ziguard.awk | 10 ++++++++++ 4 files changed, 41 insertions(+), 3 deletions(-) diff --git a/NEWS b/NEWS index 17492b3..13652fc 100644 --- a/NEWS +++ b/NEWS @@ -29,6 +29,12 @@ Unreleased, experimental changes format; in rearguard and main format, the tm_isdst flag is still zero in winter and nonzero in summer. + In 1946/7 Czechoslovakia also observed negative DST in winter. + The full effect of this change is only in vanguard format; in + rearguard and main formats, it is modeled as plain GMT without + daylight saving. Also, the dates of some 1944/5 DST transitions + in Czechoslovakia have been changed. + Release 2018d - 2018-03-22 07:05:46 -0700 diff --git a/europe b/europe index 20eb4e8..5edb686 100644 --- a/europe +++ b/europe @@ -970,9 +970,21 @@ Zone Europe/Sofia 1:33:16 - LMT 1880 # Please see the 'asia' file for Asia/Nicosia. # Czech Republic / Czechia +# +# From Paul Eggert (2018-04-14): +# The source for Czech data is: Kdy začíná a končí letní čas. +# https://kalendar.beda.cz/kdy-zacina-a-konci-letni-cas +# with one correction, taken from: +# Sbírka zákonů a nařízení republiky Československé, částka 92/1946. +# http://ftp.aspi.cz/opispdf/1946/092-1946.pdf +# which says that the winter time (negative DST) starting 1946-12-01 +# was a switch from 03:00 to 02:00 (not from 02:00 to 01:00). +# We know of no English-language name for historical Czech winter time; +# abbreviate it as "GMT", as it happened to be GMT. +# # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S -Rule Czech 1945 only - Apr 8 2:00s 1:00 S -Rule Czech 1945 only - Nov 18 2:00s 0 - +Rule Czech 1945 only - Apr Mon>=1 2:00s 1:00 S +Rule Czech 1945 only - Oct 1 2:00s 0 - Rule Czech 1946 only - May 6 2:00s 1:00 S Rule Czech 1946 1949 - Oct Sun>=1 2:00s 0 - Rule Czech 1947 only - Apr 20 2:00s 1:00 S @@ -981,7 +993,13 @@ Rule Czech 1949 only - Apr 9 2:00s 1:00 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Prague 0:57:44 - LMT 1850 0:57:44 - PMT 1891 Oct # Prague Mean Time - 1:00 C-Eur CE%sT 1944 Sep 17 2:00s + 1:00 C-Eur CE%sT 1945 May 9 + 1:00 Czech CE%sT 1946 Dec 1 3:00 +# Vanguard section, for zic and other parsers that support negative DST. +# 1:00 -1:00 GMT 1947 Feb 23 2:00 +# Rearguard section, for parsers that do not support negative DST. + 0:00 - GMT 1947 Feb 23 2:00 +# End of rearguard section. 1:00 Czech CE%sT 1979 1:00 EU CE%sT # Use Europe/Prague also for Slovakia. diff --git a/tz-link.html b/tz-link.html index 6700c7f..13a824d 100644 --- a/tz-link.html +++ b/tz-link.html @@ -728,6 +728,10 @@ zones & daylight saving time</a>.</dd> <dd>The Hydrographic and Oceanographic Service of the Chilean Navy publishes a <a href="http://www.horaoficial.cl/historia_hora.html" hreflang="es">history of Chile's official time (in Spanish)</a>.</dd> +<dt>Czech Republic</dt> +<dd><a href="https://kalendar.beda.cz/kdy-zacina-a-konci-letni-cas" +hreflang="cs">When daylight saving time starts and ends (in Czech)</a> +summarizes and cites historical DST regulations.</dd> <dt>Germany</dt> <dd>The National Institute for Science and Technology maintains the <a href="https://www.ptb.de/cms/en/fachabteilungen/abt4/fb-44/ag-441/realisation-of-…">Realisation diff --git a/ziguard.awk b/ziguard.awk index 5bfaebb..7cdceab 100644 --- a/ziguard.awk +++ b/ziguard.awk @@ -28,6 +28,16 @@ outfile != "main.zi" { in_comment = /^#/ uncomment = comment_out = 0 + # If the line should differ due to Czechoslovakia using negative SAVE values, + # uncomment the desired version and comment out the undesired one. + if (zone == "Europe/Prague" && /1947 Feb 23/) { + if (($(in_comment + 2) != "-") == vanguard) { + uncomment = in_comment + } else { + comment_out = !in_comment + } + } + # If this line should differ due to Ireland using negative SAVE values, # uncomment the desired version and comment out the undesired one. Rule_Eire = /^#?Rule[\t ]+Eire[\t ]/ -- 2.7.4

1 1

[PROPOSED] * europe: Remove "exactly" from comment; it was not exactly right.
by Paul Eggert April 14, 2018

April 14, 2018

--- europe | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/europe b/europe index 3f092a4..20eb4e8 100644 --- a/europe +++ b/europe @@ -2016,7 +2016,7 @@ Rule Neth 1938 1939 - May 15 2:00s 1:00 S Rule Neth 1945 only - Apr 2 2:00s 1:00 S Rule Neth 1945 only - Sep 16 2:00s 0 - # -# Amsterdam Mean Time was +00:19:32.13 exactly, but the .13 is omitted +# Amsterdam Mean Time was +00:19:32.13, but the .13 is omitted # below because the current format requires GMTOFF to be an integer. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Amsterdam 0:19:32 - LMT 1835 -- 2.14.3

1 0

[PROPOSED] Namibia was on DST until 2017-10-24
by Paul Eggert April 9, 2018

April 9, 2018

While we're at it, use negative DST offsets in vanguard format, since Namibia (like Ireland) used negative DST in winter. * NEWS, africa (Namibia, Africa/Windhoek), ziguard.awk: Implement this. --- NEWS | 10 ++++++++++ africa | 19 +++++++++++++++++-- ziguard.awk | 28 +++++++++++++++++++++++++--- 3 files changed, 52 insertions(+), 5 deletions(-) diff --git a/NEWS b/NEWS index 0297fd8..3bbb829 100644 --- a/NEWS +++ b/NEWS @@ -1,5 +1,15 @@ News for the tz database +Unreleased, experimental changes + + Changes to past time stamps + + For Namibia's transition from +01/+02 to plain +02, change the + transition date from 2017-09-03 at 03:00 to 2017-10-24 at 00:00. + This does not affect UTC offsets, only whether a DST regime was + in place. + + Release 2018d - 2018-03-22 07:05:46 -0700 Briefly: diff --git a/africa b/africa index 2f7217a..e564906 100644 --- a/africa +++ b/africa @@ -992,9 +992,20 @@ Link Africa/Maputo Africa/Lusaka # Zambia # the same time they would normally start DST, the first Sunday in September: # https://www.timeanddate.com/news/time/namibia-new-time-zone.html +# From Paul Eggert (2017-04-05): +# The official date of the time zone change was 2017-10-24. See: +# http://www.lac.org.na/laws/annoSTAT/Namibian%20Time%20Act%209%20of%202017.p… + # RULE NAME FROM TO TYPE IN ON AT SAVE LETTER/S +# The following has standard time in summer and negative daylight +# saving time in winter. It is for when negative SAVE values are used. +# For more about this, see the comments in 'europe' for Rule Eire. +#Rule Namibia 1994 only - Mar 21 0:00 -1:00 +01 +#Rule Namibia 1994 2017 - Sep Sun>=1 2:00 0 CAT +#Rule Namibia 1995 2017 - Apr Sun>=1 2:00 -1:00 +01 +# The following is for when SAVE values are always nonnegative. Rule Namibia 1994 only - Mar 21 0:00 0 - -Rule Namibia 1994 2016 - Sep Sun>=1 2:00 1:00 S +Rule Namibia 1994 2017 - Sep Sun>=1 2:00 1:00 S Rule Namibia 1995 2017 - Apr Sun>=1 2:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Africa/Windhoek 1:08:24 - LMT 1892 Feb 8 @@ -1003,7 +1014,11 @@ Zone Africa/Windhoek 1:08:24 - LMT 1892 Feb 8 2:00 1:00 SAST 1943 Mar 21 2:00 2:00 - SAST 1990 Mar 21 # independence 2:00 - CAT 1994 Mar 21 0:00 - 1:00 Namibia WA%sT 2017 Sep 3 2:00 +# The next line is for when negative SAVE values are used. +# 2:00 Namibia %s 2017 Oct 24 +# The next line is for when SAVE values are always nonnegative. + 1:00 Namibia WA%sT 2017 Oct 24 +# End of daylight saving. 2:00 - CAT # Niger diff --git a/ziguard.awk b/ziguard.awk index 6da3691..710b630 100644 --- a/ziguard.awk +++ b/ziguard.awk @@ -26,6 +26,7 @@ BEGIN { outfile != "main.zi" { in_comment = /^#/ + uncomment = comment_out = 0 # If this line should differ due to Ireland using negative SAVE values, # uncomment the desired version and comment out the undesired one. @@ -37,11 +38,32 @@ outfile != "main.zi" { if ((Rule_Eire \ || (Zone_Dublin_post_1968 && $(in_comment + 3) == "IST/GMT")) \ == vanguard) { - sub(/^#/, "") - } else if (/^[^#]/) { - sub(/^/, "#") + uncomment = in_comment + } else { + comment_out = !in_comment } } + + # If this line should differ due to Namibia using negative SAVE values, + # uncomment the desired version and comment out the undesired one. + Rule_Namibia = /^#?Rule[\t ]+Namibia[\t ]/ + Zone_using_Namibia_rule \ + = (zone == "Africa/Windhoek" && /^#?[\t ]+[12]:00[\t ]/ \ + && $(in_comment + 2) == "Namibia") + if (Rule_Namibia || Zone_using_Namibia_rule) { + if (in_comment == vanguard) { + uncomment = in_comment + } else { + comment_out = !in_comment + } + } + + if (uncomment) { + sub(/^#/, "") + } + if (comment_out) { + sub(/^/, "#") + } } # If a Link line is followed by a Zone line for the same data, comment -- 2.14.3

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[PATCH] * Makefile, strftime.c, zic.8: alternate -> alternative
by Paul Eggert April 9, 2018

April 9, 2018

--- Makefile | 4 ++-- strftime.c | 2 +- zic.8 | 8 ++++---- 3 files changed, 7 insertions(+), 7 deletions(-) diff --git a/Makefile b/Makefile index 23599ce..2365d7c 100644 --- a/Makefile +++ b/Makefile @@ -21,7 +21,7 @@ DATAFORM= main # Change the line below for your time zone (after finding the zone you want in # the time zone files, or adding it to a time zone file). -# Alternately, if you discover you've got the wrong time zone, you can just +# Alternatively, if you discover you've got the wrong time zone, you can just # zic -l rightzone # to correct things. # Use the command @@ -38,7 +38,7 @@ LOCALTIME= GMT # template file are used to determine "spring forward" and "fall back" days and # times; the environment variable itself specifies UT offsets of standard and # daylight saving time. -# Alternately, if you discover you've got the wrong time zone, you can just +# Alternatively, if you discover you've got the wrong time zone, you can just # zic -p rightzone # to correct things. # Use the command diff --git a/strftime.c b/strftime.c index 6da3fb9..e855890 100644 --- a/strftime.c +++ b/strftime.c @@ -224,7 +224,7 @@ label: ** %Ec %EC %Ex %EX %Ey %EY ** %Od %oe %OH %OI %Om %OM ** %OS %Ou %OU %OV %Ow %OW %Oy - ** are supposed to provide alternate + ** are supposed to provide alternative ** representations. */ goto label; diff --git a/zic.8 b/zic.8 index 4251868..97644ac 100644 --- a/zic.8 +++ b/zic.8 @@ -372,7 +372,7 @@ begin the field with a minus sign if time must be subtracted from UT. .TP .B RULES The name of the rules that apply in the time zone or, -alternately, an amount of time to add to local standard time. +alternatively, an amount of time to add to local standard time. If this field is .B \*- then standard time always applies in the time zone. @@ -386,7 +386,7 @@ The pair of characters is used to show where the .q "variable part" of the time zone abbreviation goes. -Alternately, a format can use the pair of characters +Alternatively, a format can use the pair of characters .B %z to stand for the UT offset in the form .RI \(+- hh , @@ -399,7 +399,7 @@ using the shortest form that does not lose information, where and .I ss are the hours, minutes, and seconds east (+) or west (\(mi) of UT. -Alternately, +Alternatively, a slash (/) separates standard and daylight abbreviations. To conform to POSIX, a time zone abbreviation should contain only @@ -455,7 +455,7 @@ field should appear as the field in some zone line. The .B LINK-NAME -field is used as an alternate name for that zone; +field is used as an alternative name for that zone; it has the same syntax as a zone line's .B NAME field. -- 2.7.4

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[PROPOSED 1/2] * .gitignore: Ignore .patch and .tzs files.
by Paul Eggert April 8, 2018

April 8, 2018

--- .gitignore | 2 ++ 1 file changed, 2 insertions(+) diff --git a/.gitignore b/.gitignore index bc6fc25..1e62d11 100644 --- a/.gitignore +++ b/.gitignore @@ -3,8 +3,10 @@ *.a *.asc *.o +*.patch *.tar.* *.txt +*.tzs *.zi *~ ChangeLog -- 2.14.3

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[PROPOSED] Mention Zone names with two slashes
by Paul Eggert April 6, 2018

April 6, 2018

* theory.html: Mention that some zone names have two slashes, e.g., America/Indiana/Petersburg. Use past tense for Mars Pathfinder. Avoid contractions. Use full zone names in examples and omit no-longer-needed quotes. Add URLs and fix typos. --- theory.html | 105 +++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 61 insertions(+), 44 deletions(-) diff --git a/theory.html b/theory.html index 596b32c..ba57653 100644 --- a/theory.html +++ b/theory.html @@ -53,7 +53,7 @@ However, the database is not designed for and does not suffice for applications requiring accurate handling of all past times everywhere, as it would take far too much effort and guesswork to record all details of pre-1970 civil timekeeping. -Athough some information outside the scope of the database is +Although some information outside the scope of the database is collected in a file <code>backzone</code> that is distributed along with the database proper, this file is less reliable and does not necessarily follow database guidelines. @@ -79,7 +79,7 @@ flip back and forth between two alternatives, and the rules themselves can change at times. Whether and when a <code><abbr>tz</abbr></code> region changes its clock, and even the region's notional base offset from UTC, are variable. -It doesn't even really make sense to talk about a region's +It does not always make sense to talk about a region's "base offset", since it is not necessarily a single number. </p> @@ -92,8 +92,8 @@ Each <code><abbr>tz</abbr></code> region has a unique name that corresponds to a set of time zone rules. Inexperienced users are not expected to select these names unaided. Distributors should provide documentation and/or a simple selection -interface that explains the names; for one example, see the 'tzselect' -program in the <code><abbr>tz</abbr></code> code. +interface that explains the names; for one example, see the +<code>tzselect</code> program in the <code><abbr>tz</abbr></code> code. The <a href="http://cldr.unicode.org/">Unicode Common Locale Data Repository</a> contains data that may be useful for other selection interfaces. @@ -137,6 +137,9 @@ region. North and South America share the same area, '<code>America</code>'. Typical names are '<code>Africa/Cairo</code>', '<code>America/New_York</code>', and '<code>Pacific/Honolulu</code>'. +Some names are further qualified to help avoid confusion; for example, +'<code>America/Indiana/Petersburg</code>' distinguishes Petersburg, +Indiana from other Petersburgs in America. </p> <p> @@ -159,7 +162,8 @@ in decreasing order of importance: <code>TZ</code> strings</a>. A file name component must not exceed 14 characters or start with '<code>-</code>'. - E.g., prefer '<code>Brunei</code>' to '<code>Bandar_Seri_Begawan</code>'. + E.g., prefer <code>Asia/Brunei</code> to + <code>Asia/Bandar_Seri_Begawan</code>. Exceptions: see the discussion of legacy names below. </li> <li> @@ -177,8 +181,8 @@ in decreasing order of importance: name <var>AB</var> (ignoring case), then <var>B</var> must not start with '<code>/</code>', as a regular file cannot have the same name as a directory in POSIX. - For example, '<code>America/New_York</code>' precludes - '<code>America/New_York/Bronx</code>'. + For example, <code>America/New_York</code> precludes + <code>America/New_York/Bronx</code>. </li> <li> Uninhabited regions like the North Pole and Bouvet Island @@ -193,50 +197,56 @@ in decreasing order of importance: </li> <li> If all the clocks in a region have agreed since 1970, - don't bother to include more than one location + do not bother to include more than one location even if subregions' clocks disagreed before 1970. Otherwise these tables would become annoyingly large. </li> <li> If a name is ambiguous, use a less ambiguous alternative; e.g., many cities are named San José and Georgetown, so - prefer '<code>Costa_Rica</code>' to '<code>San_Jose</code>' and - '<code>Guyana</code>' to '<code>Georgetown</code>'. + prefer <code>America/Costa_Rica</code> to + <code>America/San_Jose</code> and <code>America/Guyana</code> + to <code>America/Georgetown</code>. </li> <li> Keep locations compact. Use cities or small islands, not countries or regions, so that any future changes do not split individual locations into different <code><abbr>tz</abbr></code> regions. - E.g., prefer '<code>Paris</code>' to '<code>France</code>', since + E.g., prefer <code>Europe/Paris</code> to <code>Europe/France</code>, + since <a href="https://en.wikipedia.org/wiki/Time_in_France#History">France has had multiple time zones</a>. </li> <li> - Use mainstream English spelling, e.g., prefer '<code>Rome</code>' - to '<code>Roma</code>', and prefer '<code>Athens</code>' to the - Greek '<code>Αθήνα</code>' or the Romanized '<code>Athína</code>'. + Use mainstream English spelling, e.g., prefer + <code>Europe/Rome</code> to <code>Europe/Roma</code>, and + prefer <code>Europe/Athens</code> to the Greek + <code>Europe/Αθήνα</code> or the Romanized + <code>Europe/Athína</code>. The POSIX file name restrictions encourage this guideline. </li> <li> Use the most populous among locations in a region, - e.g., prefer '<code>Shanghai</code>' to - '<code>Beijing</code>'. + e.g., prefer <code>Asia/Shanghai</code> to + <code>Asia/Beijing</code>. Among locations with similar populations, pick the best-known - location, e.g., prefer '<code>Rome</code>' to - '<code>Milan</code>'. + location, e.g., prefer <code>Europe/Rome</code> to + <code>Europe/Milan</code>. </li> <li> - Use the singular form, e.g., prefer '<code>Canary</code>' to - '<code>Canaries</code>'. + Use the singular form, e.g., prefer <code>Atlantic/Canary</code> to + <code>Atlantic/Canaries</code>. </li> <li> Omit common suffixes like '<code>_Islands</code>' and '<code>_City</code>', unless that would lead to ambiguity. - E.g., prefer '<code>Cayman</code>' to - '<code>Cayman_Islands</code>' and '<code>Guatemala</code>' to - '<code>Guatemala_City</code>', but prefer - '<code>Mexico_City</code>' to '<code>Mexico</code>' + E.g., prefer <code>America/Cayman</code> to + <code>America/Cayman_Islands</code> and + <code>America/Guatemala</code> to + <code>America/Guatemala_City</code>, but prefer + <code>America/Mexico_City</code> to + <code>America/Mexico</code> because <a href="https://en.wikipedia.org/wiki/Time_in_Mexico">the country of Mexico has several time zones</a>. </li> @@ -245,13 +255,14 @@ in decreasing order of importance: </li> <li> Omit '<code>.</code>' from abbreviations in names. - E.g., prefer '<code>St_Helena</code>' to '<code>St._Helena</code>'. + E.g., prefer <code>Atlantic/St_Helena</code> to + <code>Atlantiic/St._Helena</code>. </li> <li> Do not change established names if they only marginally violate the above guidelines. - For example, don't change the existing name '<code>Rome</code>' to - '<code>Milan</code>' merely because Milan's population has grown + For example, do not change the existing name <code>Europe/Rome</code> to + <code>Europe/Milan</code> merely because Milan's population has grown to be somewhat greater than Rome's. </li> <li> @@ -318,8 +329,10 @@ in decreasing order of importance: Use three to six characters that are ASCII alphanumerics or '<code>+</code>' or '<code>-</code>'. Previous editions of this database also used characters like - '<code> </code>' and '<code>?</code>', but these characters have a - special meaning to the shell and cause commands like + space and '<code>?</code>', but these characters have a + special meaning to the + <a href="https://en.wikipedia.org/wiki/Unix_shell">UNIX shell</a> + and cause commands like '<code><a href="http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set">set</a> `<a href="http://pubs.opengroup.org/onlinepubs/9699919799/utilities/date.html">date</a>`</code>' to have unexpected effects. @@ -688,7 +701,7 @@ href="https://www.dissentmagazine.org/blog/booked-a-global-history-of-time-vanes subsecond accuracy is needed. </li> <li> - Civil time was not based on atomic time before 1972, and we don't + Civil time was not based on atomic time before 1972, and we do not know the history of <a href="https://en.wikipedia.org/wiki/Earth's_rotation">earth's rotation</a> accurately enough to map <a @@ -720,7 +733,7 @@ href="https://www.dissentmagazine.org/blog/booked-a-global-history-of-time-vanes Ideally it would contain information about when data entries are incomplete or dicey. Partial temporal knowledge is a field of active research, though, - and it's not clear how to apply it here. + and it is not clear how to apply it here. </li> </ul> @@ -764,7 +777,7 @@ an older <code>zic</code>. Unfortunately, the POSIX <code>TZ</code> string takes a form that is hard to describe and is error-prone in practice. - Also, POSIX <code>TZ</code> strings can't deal with daylight + Also, POSIX <code>TZ</code> strings cannot deal with daylight saving time rules not based on the Gregorian calendar (as in Iran), or with situations where more than two time zone abbreviations or <abbr>UT</abbr> offsets are used in an area. @@ -874,7 +887,7 @@ an older <code>zic</code>. need access to multiple time zone rulesets. </li> <li> - In POSIX, there's no tamper-proof way for a process to learn the + In POSIX, there is no tamper-proof way for a process to learn the system's best idea of local wall clock. (This is important for applications that an administrator wants used only at certain times – without regard to whether the @@ -973,14 +986,16 @@ an older <code>zic</code>. by subsequent calls to <code>localtime</code>. Source code for portable applications that "must" run on local wall clock time should call <code>tzsetwall</code>; - if such code is moved to "old" systems that don't - provide <code>tzsetwall</code>, you won't be able to generate an + if such code is moved to "old" systems that do not + provide <code>tzsetwall</code>, you will not be able to generate an executable program. (These functions also arrange for local wall clock time to be used if <code>tzset</code> is called – directly or - indirectly – and there's no <code>TZ</code> environment + indirectly – and there is no <code>TZ</code> environment variable; portable applications should not, however, rely on this - behavior since it's not the way SVR2 systems behave.) + behavior since it is not the way <a + href="https://en.wikipedia.org/wiki/UNIX_System_V#SVR2"><abbr>SVR2</abbr></a> + systems behave.) </li> <li> Negative <code>time_t</code> values are supported, on systems @@ -1040,7 +1055,7 @@ The vestigial <abbr>API</abbr>s are: <li> The <a href="https://en.wikipedia.org/wiki/Version_7_Unix">7th Edition UNIX</a> <code>timezone</code> function is not present in this - package; it's impossible to reliably map <code>timezone</code>'s + package; it is impossible to reliably map <code>timezone</code>'s arguments (a "minutes west of <abbr>GMT</abbr>" value and a "daylight saving time in effect" flag) to a time zone abbreviation, and we refuse to guess. @@ -1052,7 +1067,9 @@ The vestigial <abbr>API</abbr>s are: zone abbreviation to use. </li> <li> - The <abbr>4.2BSD</abbr> <code>gettimeofday</code> function is not + The <a + href="https://en.wikipedia.org/wiki/History_of_the_Berkeley_Software_Distribution…"><abbr>4.2BSD</abbr></a> + <code>gettimeofday</code> function is not used in this package. This formerly let users obtain the current <abbr>UTC</abbr> offset and <abbr>DST</abbr> flag, but this functionality was removed in @@ -1061,7 +1078,7 @@ The vestigial <abbr>API</abbr>s are: <li> In <abbr>SVR2</abbr>, time conversion fails for near-minimum or near-maximum <code>time_t</code> values when doing conversions - for places that don't use <abbr>UT</abbr>. + for places that do not use <abbr>UT</abbr>. This package takes care to do these conversions correctly. A comment in the source code tells how to get compatibly wrong results. @@ -1170,11 +1187,11 @@ They sometimes disagree. <p> Some people's work schedules use <a href="https://en.wikipedia.org/wiki/Timekeeping on Mars">Mars time</a>. -Jet Propulsion Laboratory (JPL) coordinators have kept Mars time on -and off at least since 1997 for the +Jet Propulsion Laboratory (JPL) coordinators kept Mars time on +and off during the <a href="https://en.wikipedia.org/wiki/Mars_Pathfinder#End_of_mission">Mars Pathfinder</a> mission. -Some of their family members have also adapted to Mars time. +Some of their family members also adapted to Mars time. Dozens of special Mars watches were built for JPL workers who kept Mars time during the Mars Exploration Rovers mission (2004). These timepieces look like normal Seikos and Citizens but use Mars @@ -1262,7 +1279,7 @@ Sources for time on other planets: Jia-Rui Chong, "<a href="http://articles.latimes.com/2004/jan/14/science/sci-marstime14">Workdays Fit for a Martian</a>", <cite>Los Angeles Times</cite> - (2004-01-14), pp A1, A20-A21. + (2004-01-14), pp A1, A20–A21. </li> <li> Tom Chmielewski, -- 2.14.3

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Namibia Time Zone
by Mark Plaatje April 4, 2018

April 4, 2018

Good Day Kindly update your database to reflect that no Daylight Savings Time will be effected in 2018. https://www.timeanddate.com/time/change/namibia/windhoek?year=2018 https://www.namibian.com.na/65921/read/No-time-change-on-Sunday http://www.xinhuanet.com/english/2018-04/03/c_137086167.htm https://www.namibian.com.na/65942/read/Confusion-over-time-change Regards, Mark Plaatje Manager : Fraud Mobile Telecommunications Ltd Tel: +264818882842 Fax: E-mail: MPlaatje(a)mtc.com.na <mailto:MPlaatje@mtc.com.na>http://www.mtc.com.na [X]<http://www.mtc.com.na/> ________________________________ This e-mail message and any attachment are subject to the following terms and conditions http://www.mtc.com.na/legal/disclaimer

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[PROPOSED] New edition of Calendrical Calculations
by Paul Eggert April 3, 2018

April 3, 2018

* theory.html (Calendrical issues): Update Reingold & Dershowitz citation to 4th edition. --- theory.html | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/theory.html b/theory.html index 4d8726d..596b32c 100644 --- a/theory.html +++ b/theory.html @@ -1155,10 +1155,10 @@ based on guesswork and these guesses may be corrected or improved. Calendrical issues are a bit out of scope for a time zone database, but they indicate the sort of problems that we would run into if we extended the time zone database further into the past. -An excellent resource in this area is Nachum Dershowitz and Edward M. -Reingold, <cite><a -href="https://www.cs.tau.ac.il/~nachum/calendar-book/third-edition/">Calendrical -Calculations: Third Edition</a></cite>, Cambridge University Press (2008). +An excellent resource in this area is Edward M. Reingold +and Nachum Dershowitz, <cite><a +href="https://www.cambridge.org/fr/academic/subjects/computer-science/computing-g…">Calendrical +Calculations: The Ultimate Edition</a></cite>, Cambridge University Press (2018). Other information and sources are given in the file '<code>calendars</code>' in the <code><abbr>tz</abbr></code> distribution. They sometimes disagree. -- 2.7.4

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