* 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-legal-time-in-germany.html">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