- tz - lists.iana.org

[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

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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.

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[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

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[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

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[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

2 2

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

3 2

[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

4 6

How to force zic output to TZIF?
by Johan Kohler April 3, 2018

April 3, 2018

Hi, I have a tz client that expects the tzdata in format TZIF (that's version \nul). It has become necessary to update the tzdata but it is not feasible to update the client. Is it possible with the current 2018d release to generate output in TZIF format (as opposed to TZIF2 or TZIF3)? If so, what needs to be modified? If not, what is the suggested approach? Thanks, Johan

2 2

Western Australia time zone January 1, 2019
by Paul Eggert April 2, 2018

April 2, 2018

Today the Guardian Express of Perth reported that the government of Western Australia has decided to advance the clocks permanently from +0800 to +0900 on January 1, 2019. Presumably the time will still be called Australian Western Standard Time (AWST), as it will still differ by 30 minutes from ACST (+0930). For now, I suppose we should guess that Australia/Eucla will simultaneously switch from +0845 to +0915 so as to stay halfway between AWST and ACST. Proposed patch attached. The article concludes that the government has made several concessions to residents opposed to the measure, and lists some of them. One is that "people over the age of 60 concerned about colour bleaching from drapes and blinds can apply in writing to have the extra hour of sunshine removed from their area." See: Daylight saving coming to WA in 2019. Guardian Express. 2018-04-01. https://www.communitynews.com.au/guardian-express/news/exclusive-daylight-s…

5 5

US marks centennial of daylight saving
by Paul Eggert March 30, 2018

March 30, 2018

Tonight marks 100 years since the introduction of daylight saving time as United States federal law. On March 30/31, 1918, New York City held a New-Year's-style celebration for the public in Madison Square Garden, along with a reception at the Aldine Club for the elite. The guest of honor was Marcus M. Marks, president of the Daylight Saving Association, and uncle of the now-more-famous Johnny Marks (who was later to write "Rudolph the Red-Nosed Reindeer"). Among other things, Marks got to push the button that advanced the 8-meter clocks atop what is now known as the Met Life Tower. See: Change in time begins tomorrow. Government's new daylight regulation goes into effect at 2 A. M. No confusion expected. New York Times. 1918-03-30. https://www.nytimes.com/packages/html/mobile/change-in-time.pdf

1 0

[PROPOSED] * tz-link.html: Add worldclock.com.
by Paul Eggert March 26, 2018

March 26, 2018

--- tz-link.html | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tz-link.html b/tz-link.html index 7221777..6700c7f 100644 --- a/tz-link.html +++ b/tz-link.html @@ -239,8 +239,9 @@ These are listed roughly in ascending order of complexity and fanciness. <ul> <li><a href="https://time.is">Time.is</a> shows locations' time and zones.</li> -<li><a href="https://www.timejones.com">TimeJones.com</a> -and <a href="https://timezoneconverterapp.com">Time Zone Converter</a> +<li><a href="https://www.timejones.com">TimeJones.com</a>, +<a href="https://timezoneconverterapp.com">Time Zone Converter</a> and +<a href="http://worldclock.com">The World Clock</a> are time zone converters.</li> <li><a href="http://twiki.org/cgi-bin/xtra/tzdatepick.html">Date and Time Gateway</a> -- 2.7.4

1 0

Re: [tz] [PATCH1/1] Propose new zone for Crozet Islands
by REMI ACIEN March 25, 2018

March 25, 2018

Provenance : Courrier<https://go.microsoft.com/fwlink/?LinkId=550986> pour Windows 10 A new zone for Crozet Islands . Why not .

4 5

[PROPOSED] Spelling fixes
by Paul Eggert March 23, 2018

March 23, 2018

--- NEWS | 2 +- asia | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/NEWS b/NEWS index 8afe3a4..0297fd8 100644 --- a/NEWS +++ b/NEWS @@ -39,7 +39,7 @@ Release 2018d - 2018-03-22 07:05:46 -0700 Enderbury and Kiritimati skipped New Year's Eve 1994, not New Year's Day 1995. (Thanks to Kerry Shetline.) - Fix the 1912-01-01 transition for Portugual and its colonies. + Fix the 1912-01-01 transition for Portugal and its colonies. This transition was at 00:00 according to the new UT offset, not according to the old one. Also assume that Cape Verde switched on the same date as the rest, not in 1907. This affects diff --git a/asia b/asia index 998a7d4..7a6294a 100644 --- a/asia +++ b/asia @@ -2658,7 +2658,7 @@ Zone Asia/Karachi 4:28:12 - LMT 1907 # From Sharef Mustafa (2018-03-16): # Palestine summer time will start on Mar 24th 2018 by advancing the # clock by 60 minutes as per Palestinian cabinet decision published on -# the offical website, though the decree did not specify the exact +# the official website, though the decree did not specify the exact # time of the time shift. # http://www.palestinecabinet.gov.ps/Website/AR/NDecrees/ViewFile.ashx?ID=e7a… # -- 2.14.3

1 0

[tz-announce] 2018d release of tz code and data available
by Paul Eggert March 23, 2018

March 23, 2018

The 2018d 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: Palestine starts DST a week earlier in 2018. Add support for vanguard and rearguard data consumers. Add subsecond precision to source data format, though not to data. Changes to future time stamps In 2018, Palestine starts DST on March 24, not March 31. Adjust future predictions accordingly. (Thanks to Sharef Mustafa.) Changes to past and future time stamps Casey Station in Antarctica changed from +11 to +08 on 2018-03-11 at 04:00. (Thanks to Steffen Thorsen.) Changes to past time stamps Historical transitions for Uruguay, represented by America/Montevideo, have been updated per official legal documents, replacing previous data mainly originating from the inventions of Shanks & Pottenger. This has resulted in adjustments ranging from 30 to 90 minutes in either direction over at least two dozen distinct periods ranging from one day to several years in length. A mere handful of pre-1991 transitions are unaffected; data since then has come from more reliable contemporaneous reporting. These changes affect various timestamps in 1920-1923, 1936, 1939, 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990. Additionally, Uruguay's pre-standard-time UT offset has been adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to match the location of the Observatory of the National Meteorological Institute in Montevideo. (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.) Enderbury and Kiritimati skipped New Year's Eve 1994, not New Year's Day 1995. (Thanks to Kerry Shetline.) Fix the 1912-01-01 transition for Portugual and its colonies. This transition was at 00:00 according to the new UT offset, not according to the old one. Also assume that Cape Verde switched on the same date as the rest, not in 1907. This affects Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores, Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon. (Thanks to Michael Deckers.) Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in Turks & Caicos. Changes to past time zone abbreviations MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There is no clock change associated with the transition. Changes to build procedure The new DATAFORM macro in the Makefile lets the installer choose among three source data formats. The idea is to lessen downstream disruption when data formats are improved. * DATAFORM=vanguard installs from the latest, bleeding-edge format. DATAFORM=main (the default) installs from the format used in the 'africa' etc. files. DATAFORM=rearguard installs from a trailing-edge format. Eventually, elements of today's vanguard format should move to the main format, and similarly the main format's features should eventually move to the rearguard format. * In the current version, the main and rearguard formats are identical and match that of 2018c, so this change does not affect default behavior. The vanguard format currently contains one feature not in the main format: negative SAVE values. This improves support for Ireland, which uses Irish Standard Time (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has supported negative SAVE values for decades, and this feature should move to the main format soon. However, it will not move to the rearguard format for quite some time because some downstream parsers do not support it. * The build procedure constructs three files vanguard.zi, main.zi, and rearguard.zi, one for each format. The files represent the same data as closely as the formats allow. These three files are intended for downstream data consumers and are not installed. Zoneinfo parsers that do not support negative SAVE values should start using rearguard.zi, so that they will be unaffected when the negative-DST feature moves from vanguard to main. Bleeding-edge Zoneinfo parsers that support the new features already can use vanguard.zi; in this respect, current tzcode is bleeding-edge. The Makefile should now be safe for parallelized builds, and 'make -j to2050new.tzs' is now much faster on a multiprocessor host with GNU Make. When built with -DSUPPRESS_TZDIR, the tzcode library no longer prepends TZDIR/ to file names that do not begin with '/'. This is not recommended for general use, due to its security implications. (From a suggestion by Manuela Friedrich.) Changes to code zic now accepts subsecond precision in expressions like 00:19:32.13, which is approximately the legal time of the Netherlands from 1835 to 1937. However, because it is questionable whether the few recorded uses of non-integer offsets had subsecond precision in practice, there are no plans for tzdata to use this feature. (Thanks to Steve Allen for pointing out the limitations of historical data in this area.) The code is a bit more portable to MS-Windows. Installers can compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that reserve identifiers like 'localtime'. (Thanks to Manuela Friedrich). Changes to documentation and commentary theory.html now outlines tzdb's extensions to POSIX's model for civil time, and has a section "POSIX features no longer needed" that lists POSIX API components that are now vestigial. (From suggestions by Steve Summit.) It also better distinguishes time zones from tz regions. (From a suggestion by Guy Harris.) Commentary is now more consistent about using the phrase "daylight saving time", to match the C name tm_isdst. Daylight saving time need not occur in summer, and need not have a positive offset from standard time. Commentary about historical transitions in Uruguay has been expanded with links to many relevant legal documents. (Thanks to Tim Parenti.) Commentary now uses some non-ASCII characters with Unicode value less than U+0100, as they can be useful and should work even with older editors such as XEmacs. Here are links to the release files: https://www.iana.org/time-zones/repository/releases/tzcode2018d.tar.gz https://www.iana.org/time-zones/repository/releases/tzdata2018d.tar.gz https://www.iana.org/time-zones/repository/releases/tzdb-2018d.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 bd850bce5d292caaa5eba2c2088f6d4ad8024647 dated 2018-03-22 07:05:46 -0700 and tagged '2018d' in the development GitHub repository at <https://github.com/eggert/tz>. Here are the SHA-512 checksums for the release files: e79a95e235cd384247e4112d5154f30eb7b40f28dab4872ed9153e45bf56569949d0845bc1b9ad24b7a5f9609bdadfc892959dbf0d540dbca79b18398dc4f930 tzcode2018d.tar.gz ee961aedc34e134172523a29fb8a9358f42649d06ffcd2d8a6ad86eeb174a80af5bfc4637e9e52ecdc51fa3d01afef9fff660a69ed72904ff747a59b5634830b tzdata2018d.tar.gz 12c839846c147b83ace915e399fe447f93e83b500327fb4549b6039615f548d7167594168b5c4779ee1f33d7a1b8c2e294aa13cd35823d778617065ad9ad8ea5 tzdb-2018d.tar.lz Here are the GPG checksums for the release files: -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJas7pNAAoJEO2X6Q5iqn40dn8P+gI1f6sWKcA8iuDkRWundwBk Y92iYPChJDbgUSiWw3o+qyFmVUz0P1PZkB3rCTFhtyY8u6zCiO4+6xADyS+le3II iwwIg2yCqPxBXDXYkcFvSrXDuOo1hG009L1k9nKmv6RvO7lvr/o0K/pRQTWKiV2w jS9gPZeZ/ggTdcyaD9tzFNwDe0nCg54rwFs3Gy+YK2+8fNhLmYJCp3WJydza9zgU pBMMP868h1ZY9uWEZcWX3mstyKD4egFRfyHMj4XPVrnGwpMT5u7groiq2TZv/MXV A/HDxa4jU+El6RW0TwAVnGEwUSJ3L3I7B6/Pbf3jf+VCTYkw67cX/WrtSNop1E03 ujPZVqYr5N8HLu/VO/R2R+OccvMZ1X/URehA4068w/+ESG8X8AbRVBYGavpFmnUv uHOeOFgzcJUQqFU1fqAEdhlrYqqbnsRFJN8QX1QWwQs5fUAzNSAkAB+kTEVCAvhK 1xaxlNaZqoWqT0bYvD2TL+VLkPNHvu8RMpa/rhmjE23AWfYuSJsAABNMBpB5t6ux SbBOBeJ+a5a1rZwya0hxeX6A3BCBPXKBjnt8MjBnV1s8Ns4Ng7jQ5ZqOXtlSo4ER fYHbVQITXnE+DbuM1zF6RY1dwmCLvkxpdM5lifgiYCdcDzttsifDdrq5WM+pJsz5 3yTFJFsk6et2ekpHRugZ =MMy8 -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJas7pNAAoJEO2X6Q5iqn40BqwP/A8PU9mzxssBdQirWsuGhN3E +3hk6i7UFLrCHixbpN03y7r8ujkhRvkjLSrA2tcrYEK9t8NLkhQIrnmlVjEOQEcz +qiZWJV55kd2dhk2EE+pc8xXuqRsnId4r/xCF+D2wxl6IZpMEFelRCRiCGgszhDS FSv3UjlnpBv3uB5UgKdOFJKYcTvfOZ5jmpt1O6Ma9YNxqlc2+s8hUBR3VEtzancU +AyCoL/sUrijfGOZPSznhGJJ3lC5LkjkWqC0BYB5EI3YeClVtGWoZlD64jShJhWT pe3CAimaEibz1ty1tGz4Agdd0vQErvyCPQY6wy1pRYPW5wb++JomMVub7Uh7w/6o pvrkVaVqeiWeENoI6NRnmC+ANSaz6/lF61HM36VZ1XaCgmeCDaLHn31WKHRPctse r26++PyCIJwllaTNfGynjkAKUeBJJwwR8a/sjPeqEfEgoDKV1EpQVCBbPna3hmTq 8nzt11WsTNG+aocYr3hevSYiyxEWOLp5O9UaiTtVDc91Mhk2U9E9Fa7Zva35ZhjJ oRPS+AU5GFfWzgiW8XOLURqvwRNqUUudNaXy2wVuzwROdmboyewzB//MBavkI+r+ raI+coG2ZJoPcQmuRCUcjs1+JnNBL3sZT68/jTy2w0LURfUP9V+dUuJgjtRbMCtb Myzq3RCYNI/x3EjU/xcb =ibli -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJas7pOAAoJEO2X6Q5iqn40ursP/02PBDqd4eb8qrKrjScYt+I4 wnXMcjy9AmsfhPq1k1x6ZUI5qIbidrMD9S9m4NwKBGyvGxxcneWWJ5Yoln+K95YJ tCtm40eHypeVUlsXJExv3JB0hJ7d7eY2olbY/DcK6CTYt7R4amGU/ClCQpEIVTz2 HcVeH8oOPRUG0STyzKh2lPF0Wua6LUGp9/nZWgsETsXrAQ8MaC/vlyrjiEJsvwP1 65bOoNiRKiGU7tp6JhFE8v85vLKgkzmHeysWJdMt0aczH1DMwlSWS9ViEauLugK7 K0ERNC22WwEzya0EKmTMcRFHYIT1B9/dg0Tbb2h2KKRqu7kzd2NVr6ap5Cu6ezYO hThz6i09OL6ADSwSk4c6JeUUjX7rGG6DNu0pCQYlNJ9xIhi+U/FAuTvzBfU3uJe3 8akO1UGwUWA/TwtnQTv08uGGia+Wt/GbQStkidZFVvdbXcjSH39GlhRXRWDKSOCv wDVNMkopDQOsxwoFgAE45dacQZh2Qv29eT4pG6Eo2J+eXJR2lb5edQkDZNLk2DcE 6frcVchrdBeaUUSA1+ssH3B+hVwwJ7IX/FCwhKDZgxyy67oqGVChkeUjes4GJ5vB 0t7/XZTORvsH6XwBNDKoXS0fswtZiwhPr3YV1nZHwKCa0OWIs9WsPt587K82Hlsf mROMmzivSut43pdALRCr =zKoc -----END PGP SIGNATURE----- _______________________________________________ tz-announce mailing list tz-announce(a)iana.org https://mm.icann.org/mailman/listinfo/tz-announce

1 0

[PROPOSED] * tz-link.html: Tweak URLs.
by Paul Eggert March 22, 2018

March 22, 2018

--- tz-link.html | 56 +++++++++++++++++++++++++++----------------------------- 1 file changed, 27 insertions(+), 29 deletions(-) diff --git a/tz-link.html b/tz-link.html index f3ac4ed..7221777 100644 --- a/tz-link.html +++ b/tz-link.html @@ -7,7 +7,9 @@ <body> <h1>Sources for time zone and daylight saving time data</h1> <p> -Time zone and daylight saving rules are controlled by individual +<a href="https://en.wikipedia.org/wiki/Time_zone">Time zone</a> and +<a href="https://en.wikipedia.org/wiki/Daylight_saving_time">daylight-saving</a> +rules are controlled by individual governments. They are sometimes changed with little notice, and their histories and planned futures are often recorded only fitfully. Here is a summary of attempts to organize and record relevant data in this @@ -20,12 +22,9 @@ time zone database contains code and data that represent the history of local time for many representative locations around the globe. It is updated periodically to reflect changes made by political bodies -to <a href="https://en.wikipedia.org/wiki/Time_zone">time zone</a> -boundaries and -<a href="https://en.wikipedia.org/wiki/Daylight_saving_time">daylight-saving</a> -rules. -This database (often called <code>zoneinfo</code> or -<code><abbr>tz</abbr></code>) +to time zone boundaries and daylight saving rules. +This database (known as <code><abbr>tz</abbr></code>, +<code><abbr>tzdb</abbr></code>, or <code>zoneinfo</code>) is used by several implementations, including <a href="https://www.gnu.org/software/libc/">the @@ -109,7 +108,7 @@ gzip -dc tzdata-latest.tar.gz | tar -xf - release in a single-tarball format containing extra data useful for regression testing:</p> <pre style="margin-left: 2em"><code>wget <a href="https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz">https://www.iana.org/time-zones/repository/tzdb-latest.tar.lz</a> -<a href="http://www.nongnu.org/lzip/">lzip</a> -dc tzdb-latest.tar.lz | tar -xf - +<a href="https://www.nongnu.org/lzip/">lzip</a> -dc tzdb-latest.tar.lz | tar -xf - </code></pre> <p>These commands use convenience links to the latest release of the <code><abbr>tz</abbr></code> database hosted by the @@ -130,7 +129,7 @@ Since version 2016h, each release has contained a text file named The releases are also available in an <a href="ftp://ftp.iana.org/tz/releases/"><abbr title="File Transfer Protocol">FTP</abbr> directory</a> via a -less-secure protocol .</p> +less-secure protocol.</p> <p>Alternatively, a development repository of code and data can be retrieved from <a href="https://github.com">GitHub</a> via the shell command:</p> @@ -192,7 +191,7 @@ href="http://www.oracle.com/technetwork/java/javase/tzupdater-readme-136440.html Java, <a href="http://www.joda.org/joda-time/tz_update.html">Joda-Time</a>, <a href="https://dev.mysql.com/doc/refman/en/time-zone-support.html">MySQL</a>, and <a -href="http://nodatime.org/userguide/tzdb">Noda Time</a> (see below). +href="https://nodatime.org/userguide/tzdb">Noda Time</a> (see below). </p> <p>Sources for the <code><abbr>tz</abbr></code> database are <a href="https://en.wikipedia.org/wiki/UTF-8"><abbr @@ -203,7 +202,7 @@ title="linefeed">LF</abbr></a>, which can be modified by common text editors such as <a href="https://www.gnu.org/software/emacs/">GNU Emacs</a>, <a href="https://wiki.gnome.org/Apps/Gedit">gedit</a>, and -<a href="http://www.vim.org">vim</a>. +<a href="https://www.vim.org">vim</a>. Specialized source-file editing can be done via the <a href="https://packagecontrol.io/packages/zoneinfo">Sublime zoneinfo</a> package for <a @@ -258,7 +257,7 @@ timezone information for all countries</a> displays tables of DST rules. Worldwide</a> lets you sort zone names and convert times.</li> <li><a href="https://24timezones.com">24TimeZones</a> has a world time map and a time converter.</li> -<li><a href="http://www.zeitverschiebung.net/en/">Time Difference</a> +<li><a href="https://www.zeitverschiebung.net/en/">Time Difference</a> calculates the current time difference between locations.</li> <li><a href="http://www.wx-now.com">Weather Now</a> and <a href="http://www.thetimenow.com">The Time Now</a> list the weather too.</li> @@ -290,7 +289,7 @@ variant <a href="https://tools.ietf.org/html/rfc6321">xCal</a> title="Extensible Markup Language">XML</abbr></a> format, and a variant <a href="https://tools.ietf.org/html/rfc7265">jCal</a> (Internet <abbr>RFC</abbr> 7265) -uses <a href="http://www.json.org"><abbr +uses <a href="https://www.json.org"><abbr title="JavaScript Object Notation">JSON</abbr></a> format.</li> </ul> <h2 id="compilers">Other <code><abbr>tz</abbr></code> compilers</h2> @@ -374,7 +373,7 @@ License">LGPL</abbr>)</a>.</li> <li><abbr>ICU</abbr> (mentioned <a href="#ICU">above</a>) contains compilers and Java-based libraries.</li> </ul> -<li><a href="http://nodatime.org">Noda Time – Date and +<li><a href="https://nodatime.org">Noda Time – Date and time <abbr>API</abbr> for .NET</a> and <a href="http://www.babiej.demon.nl/Tz4Net/main.htm">TZ4Net</a> are similar to Joda-Time and Time4J, but for the .NET framework instead of @@ -458,7 +457,7 @@ library that reads tz binary files and converts time stamps from one time zone or format to another. It is used by <a href="https://secure.php.net"><abbr title="PHP: Hypertext Preprocessor">PHP</abbr></a>, -<a href="http://hhvm.com"><abbr title="HipHop Virtual Machine">HHVM</abbr></a>, +<a href="https://hhvm.com"><abbr title="HipHop Virtual Machine">HHVM</abbr></a>, and <a href="https://www.mongodb.com">MongoDB</a>. It is freely available under the <abbr>MIT</abbr> license.</li> <li><a href="https://github.com/bigeasy/timezone">Timezone</a> is a @@ -518,7 +517,7 @@ the older, proprietary method of Microsoft Windows 2000 and later, which stores time zone data in the <a href="https://en.wikipedia.org/wiki/Windows_Registry">Windows Registry</a>. The <a -href="http://unicode.org/cldr/charts/latest/supplemental/zone_tzid.html">Zone → +href="https://unicode.org/cldr/charts/latest/supplemental/zone_tzid.html">Zone → Tzid table</a> or <a href="https://unicode.org/repos/cldr/trunk/common/supplemental/windowsZones.xml"><abbr>XML</abbr> file</a> of the <abbr>CLDR</abbr> data maps proprietary zone IDs @@ -528,7 +527,7 @@ href="https://www.oracle.com/java/index.html">Oracle Java</a> contains a copy of a subset of a recent <code><abbr>tz</abbr></code> database in a Java-specific format.</li> -<li><a href="http://www.relativedata.com/time-zone-master">Time Zone +<li><a href="https://www.relativedata.com/time-zone-master">Time Zone Master</a> is a Microsoft Windows clock program that can automatically download, compile and use <code>tz</code> releases. The Basic version is free.</li> @@ -543,8 +542,8 @@ licenses</a> to <code><abbr>tz</abbr></code> contributors.</li> <li><a href="https://www.astro.com/atlas">Time-zone Atlas</a> is Astrodienst's Web version of Shanks and Pottenger's time zone history atlases also published in <a -href="http://astrocom.com/astrology-products/software/acs-atlas-software">software</a> -form by <a href="http://astrocom.com">ACS-Starcrafts</a>. +href="https://astrocom.com/astrology-products/software/acs-atlas-software">software</a> +form by <a href="https://astrocom.com">ACS-Starcrafts</a>. These atlases are extensive but unreliable, as Shanks appears to have guessed many <abbr>UT</abbr> offsets and transitions. The atlases cite no sources and do not indicate which entries are guesswork.</li> @@ -552,7 +551,7 @@ sources and do not indicate which entries are guesswork.</li> its own <code>tztab</code>(4) format.</li> <li>Microsoft Windows has proprietary data mentioned <a href="#System.TimeZoneInfo">above</a>.</li> -<li><a href="http://www.worldtimeserver.com">World Time Server</a> +<li><a href="https://www.worldtimeserver.com">World Time Server</a> is another time zone database.</li> <li><a href="http://tycho.usno.navy.mil/tzones.html">World Time Zones</a> contains data from the Time Service Department of the @@ -578,14 +577,14 @@ recent editions. The pictorial quality is good, but the maps do not indicate daylight saving time, and parts of the data are a few years out of date.</li> -<li><a href="http://www.worldtimezone.com">Current time around the world +<li><a href="https://www.worldtimezone.com">Current time around the world and standard time zones map of the world</a> has several fancy time zone maps; it covers Russia particularly well. The maps' pictorial quality is not quite as good as the <abbr>CIA</abbr>'s but the maps are more up to date.</li> <li><a -href="http://blog.poormansmath.net/how-much-is-time-wrong-around-the-world/">How +href="https://blog.poormansmath.net/how-much-is-time-wrong-around-the-world/">How much is time wrong around the world?</a> maps the difference between mean solar and standard time, highlighting areas such as western China where the two differ greatly. It's a bit out of date, unfortunately.</li> @@ -666,9 +665,8 @@ political subdivision data related to time zones.</li> <li><a href="http://home.kpn.nl/vanadovv/time/Multizones.html">Time zone boundaries for multizone countries</a> summarizes legal boundaries between time zones within countries.</li> -<li>Manifold.net's <a -href="http://manifold.net/info/freestuff.shtml">Free Downloads for -Manifold System Users</a> includes a Manifold-format map of +<li><a href="http://manifold.net/info/freestuff.shtml">Manifold Software +– GIS and Database Tools</a> includes a Manifold-format map of world time zone boundaries distributed under the <abbr>GPL</abbr>.</li> <li>A ship within the <a @@ -808,12 +806,12 @@ href="https://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol"><abbr>D option for a server to configure a client's time zone and daylight saving settings automatically.</li> <li><a -href="http://www.cv.nrao.edu/~rfisher/Ephemerides/times.html">Astronomical +href="https://www.cv.nrao.edu/~rfisher/Ephemerides/times.html">Astronomical Times</a> explains more abstruse astronomical time scales like <abbr title="Terrestrial Dynamic Time">TDT</abbr>, <abbr title="Geocentric Coordinate Time">TCG</abbr>, and <abbr title="Barycentric Dynamic Time">TDB</abbr>. -<a href="http://www.ucolick.org/~sla/leapsecs/timescales.html">Time +<a href="https://www.ucolick.org/~sla/leapsecs/timescales.html">Time Scales</a> goes into more detail, particularly for historical variants.</li> <li>The <a href="https://www.iau.org"><abbr title="International Astronomical Union">IAU</abbr></a>'s <a @@ -859,7 +857,7 @@ and Klepczynski's 1999 proposal to discontinue leap seconds</a>, discussed further in <a href="https://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf">The leap second: its history and possible future</a>. -<a href="http://www.ucolick.org/~sla/leapsecs/"><abbr>UTC</abbr> +<a href="https://www.ucolick.org/~sla/leapsecs/"><abbr>UTC</abbr> might be redefined without Leap Seconds</a> gives pointers on this contentious issue, which was active until 2015 and could become active @@ -873,7 +871,7 @@ zone names, abbreviations, identifiers, and formats. For example, it contains French translations for "Eastern European Summer Time", "<abbr title="Eastern European Summer Time">EEST</abbr>", and "Bucharest". Its -<a href="http://unicode.org/cldr/charts/latest/by_type/">by-type +<a href="https://unicode.org/cldr/charts/latest/by_type/">by-type charts</a> show these values for many locales. Data values are available in both <abbr title="Locale Data Markup Language">LDML</abbr> (an <abbr>XML</abbr> format) and <abbr>JSON</abbr>. -- 2.7.4

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Re: [tz] proposed tz data changes for Iran, Sri Lanka, Alberta, Thule, etc.
by REMI ACIEN March 21, 2018

March 21, 2018

Provenance : Courrier<https://go.microsoft.com/fwlink/?LinkId=550986> pour Windows 10 For Zone Asia/Seoul +8 :27 :52 . Why not .

3 2

[PROPOSED] Put ziguard.awk in tzdata and tzdb tarballs
by Paul Eggert March 20, 2018

March 20, 2018

(Problem reported by Patsy Franklin.) * Makefile (AWK_SCRIPTS): Add ziguard.awk. --- Makefile | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 3c0479a..c69e01b 100644 --- a/Makefile +++ b/Makefile @@ -486,7 +486,8 @@ TZDATA_ZI_DEPS= ziguard.awk zishrink.awk version $(TDATA) $(PACKRATDATA) DSTDATA_ZI_DEPS= ziguard.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 +AWK_SCRIPTS= checklinks.awk checktab.awk leapseconds.awk \ + ziguard.awk zishrink.awk MISC= $(AWK_SCRIPTS) zoneinfo2tdf.pl TZS_YEAR= 2050 TZS= to$(TZS_YEAR).tzs @@ -903,6 +904,9 @@ tarballs traditional_tarballs signatures traditional_signatures: version VERSION=`cat version` && \ $(MAKE) VERSION="$$VERSION" $@_version +# These *_version rules are intended for use if VERSION is set by some +# other means. Ordinarily these rules are used only by the above +# non-_version rules, which set VERSION on the 'make' command line. tarballs_version: traditional_tarballs_version tzdb-$(VERSION).tar.lz traditional_tarballs_version: \ tzcode$(VERSION).tar.gz tzdata$(VERSION).tar.gz -- 2.14.3

1 0

switches at 1883-11-18 at the same instant
by Michael H Deckers March 20, 2018

March 20, 2018

On 2018-03-19 09:18, Glenn A. Walsh wrote in a post to a different mailing list: > Centennial: Official Enactment of U.S. Time Zones & Daylight Saving Time > A century ago today (March 19), U.S.President Woodrow Wilson signed into law the Standard Time Act of1918, which officially established time zones in the United States aswell as Daylight Saving Time. Although time zones had beenunofficially observed for a few decades. > MORE INFO - CLICK ON IMAGE OR LINK --- LIKE THIS POST? - PLEASE SHARE! > Link >>> http://spacewatchtower.blogspot.com/2018/03/centennial-official-enactment-o… > The link describes (among many other things) how the Allegheny Observatory synchronized the switch of US railway times to grid time zones. As one would expect, the switch was done at a single instant, when UT was 1883-11-18 + 18 h. This differs from the current description in tzdb which uses different instants for different target time zones -- not a likely choice for simplifying a nationwide railway schedule. Thus I propose: - Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:07:02 + Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 10:07:02 - Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:15:11 + Zone America/Boise -7:44:49 - LMT 1883 Nov 18 10:15:11 - Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 11:31:42 + Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 10:31:42 - Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00:04 + Zone America/Denver -6:59:56 - LMT 1883 Nov 18 11:00:04 - Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 12:12:53 + Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 11:12:53 - Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 12:14:21 + Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 11:14:21 - Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 12:14:48 + Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 11:14:48 - Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:03:58 + Zone America/New_York -4:56:02 - LMT 1883 Nov 18 13:03:58 Michael Deckers.

3 5

[PROPOSED] Update .PHONY list
by Paul Eggert March 20, 2018

March 20, 2018

* Makefile (.PHONY): Update to match current Makefile contents. --- Makefile | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/Makefile b/Makefile index 979c0a2..3c0479a 100644 --- a/Makefile +++ b/Makefile @@ -964,14 +964,17 @@ zic.o: private.h tzfile.h version.h .KEEP_STATE: .PHONY: ALL INSTALL all -.PHONY: check check_character_set check_links +.PHONY: check check_character_set check_links check_name_lengths .PHONY: check_public check_sorted check_tables .PHONY: check_time_t_alternatives check_tzs check_web check_white_space .PHONY: check_zishrink -.PHONY: clean clean_misc force_tzs +.PHONY: clean clean_misc dummy.zd force_tzs .PHONY: install install_data maintainer-clean names .PHONY: posix_only posix_packrat posix_right .PHONY: public right_only right_posix signatures signatures_version -.PHONY: tarballs tarballs_version typecheck +.PHONY: tarballs tarballs_version +.PHONY: traditional_signatures traditional_signatures_version +.PHONY: traditional_tarballs traditional_tarballs_version +.PHONY: typecheck .PHONY: zonenames zones .PHONY: $(ZDS) -- 2.14.3

1 0

Re: [tz] [PATCH] * asia (Asia/Seoul) correct DST.
by REMI ACIEN March 19, 2018

March 19, 2018

For Zone Asia/Seoul LMT + 8 :26 :52 . Provenance : Courrier<https://go.microsoft.com/fwlink/?LinkId=550986> pour Windows 10

2 1

Re: [tz] more on Palm Springs
by Paul Eggert March 18, 2018

March 18, 2018

Steve Allen wrote: > If inserting the Palm Springs story into tzdb is going to happen then > UCR has scanned copies of the local paper. Thanks for the URLs. Another city of two-timers, eh? Proposed patches attached.

1 0

[PATCH] * backzone: Chillicothe, city of two-timers.
by Paul Eggert March 18, 2018

March 18, 2018

--- backzone | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/backzone b/backzone index 71cb066..de247f0 100644 --- a/backzone +++ b/backzone @@ -274,6 +274,16 @@ Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown -5:07:10 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST +# United States +# +# From Paul Eggert (2018-03-18): +# America/Chillicothe would be tricky, as it was a city of two-timers: +# "To prevent a constant mixup at Chillicothe, caused by the courthouse +# clock running on central time and the city running on 'daylight saving' +# time, a third hand was added to the dial of the courthouse clock." +# -- Ohio news in brief. The Cedarville Herald. 1920-05-21;43(21):1 (col. 5) +# https://digitalcommons.cedarville.edu/cedarville_herald/794 + # Canada Zone America/Coral_Harbour -5:32:40 - LMT 1884 -5:00 NT_YK E%sT 1946 -- 2.14.3

1 0