"Olson, Arthur David \(NIH/NCI\)" <olsona@dc37a.nci.nih.gov> writes:
The systemv stuff was included way back in 1986 when System V was still relevant; twenty years later it can presumably be dispensed with.
That sounds good to me. By the way, I tried but failed to find documentation about exactly which TZ settings Unix System V supported, and when this was introduced (SVR1? SVR3? etc.). If anybody has more concrete information about this please let me know. For now, the patch below sticks with the same small set of seven backward-compatibility settings that the current tz database supports.
If we do end up with two copies of the US rules, we'll want to make sure that there's a comment with each copy indicating the need to keep it in sync with the other copy.
Elsewhere we have been using two copies (e.g., Russia in "europe" versus RussiaAsia in "asia") so it is a little more consistent to keep doing that, until we come up with a better way to attack the issue. Here's a revised patch along those lines. It assumes that the "systemv" file is removed. --- backward 2005/08/29 15:54:31 2005.13 +++ backward 2005/11/22 18:05:09 2005.13.0.3 @@ -42,7 +42,6 @@ Link America/Rio_Branco Brazil/Acre Link America/Noronha Brazil/DeNoronha Link America/Sao_Paulo Brazil/East Link America/Manaus Brazil/West -Link America/Chicago CST6CDT Link America/Halifax Canada/Atlantic Link America/Winnipeg Canada/Central Link America/Regina Canada/East-Saskatchewan @@ -55,8 +54,6 @@ Link America/Whitehorse Canada/Yukon Link America/Santiago Chile/Continental Link Pacific/Easter Chile/EasterIsland Link America/Havana Cuba -Link America/Panama EST -Link America/New_York EST5EDT Link Africa/Cairo Egypt Link Europe/Dublin Eire Link Europe/London Europe/Belfast @@ -67,7 +64,6 @@ Link Etc/GMT GMT+0 Link Etc/GMT GMT-0 Link Etc/GMT GMT0 Link Etc/GMT Greenwich -Link Pacific/Honolulu HST Link Asia/Hong_Kong Hongkong Link Atlantic/Reykjavik Iceland Link Asia/Tehran Iran @@ -76,8 +72,6 @@ Link America/Jamaica Jamaica Link Asia/Tokyo Japan Link Pacific/Kwajalein Kwajalein Link Africa/Tripoli Libya -Link America/Phoenix MST -Link America/Denver MST7MDT Link America/Tijuana Mexico/BajaNorte Link America/Mazatlan Mexico/BajaSur Link America/Mexico_City Mexico/General @@ -85,7 +79,6 @@ Link Pacific/Auckland NZ Link Pacific/Chatham NZ-CHAT Link America/Denver Navajo Link Asia/Shanghai PRC -Link America/Los_Angeles PST8PDT Link Pacific/Pago_Pago Pacific/Samoa Link Pacific/Truk Pacific/Yap Link Europe/Warsaw Poland @@ -111,3 +104,35 @@ Link Etc/UTC UTC Link Etc/UTC Universal Link Europe/Moscow W-SU Link Etc/UTC Zulu + + +# A copy of the US rules from the "northamerica" file. +# The copy is so that "backward" can be compiled independently. +# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S +Rule US-back 1918 1919 - Mar lastSun 2:00 1:00 D +Rule US-back 1918 1919 - Oct lastSun 2:00 0 S +Rule US-back 1942 only - Feb 9 2:00 1:00 W # War +Rule US-back 1945 only - Aug 14 23:00u 1:00 P # Peace +Rule US-back 1945 only - Sep 30 2:00 0 S +Rule US-back 1967 2006 - Oct lastSun 2:00 0 S +Rule US-back 1967 1973 - Apr lastSun 2:00 1:00 D +Rule US-back 1974 only - Jan 6 2:00 1:00 D +Rule US-back 1975 only - Feb 23 2:00 1:00 D +Rule US-back 1976 1986 - Apr lastSun 2:00 1:00 D +Rule US-back 1987 2006 - Apr Sun>=1 2:00 1:00 D +Rule US-back 2007 max - Mar Sun>=8 2:00 1:00 D +Rule US-back 2007 max - Nov Sun>=1 2:00 0 S +# Keep the above rules in sync with the "US" rules in the "northamerica" file. + +# The following zones are for backward compatibility with TZ settings +# supported by 1980s-era Unix System V. + +# Zone NAME GMTOFF RULES FORMAT +Zone EST -5:00 - EST +Zone MST -7:00 - MST +Zone HST -10:00 - HST + +Zone EST5EDT -5:00 US-back E%sT +Zone CST6CDT -6:00 US-back C%sT +Zone MST7MDT -7:00 US-back M%sT +Zone PST8PDT -8:00 US-back P%sT --- northamerica 2005/11/18 06:54:05 2005.14.0.1 +++ northamerica 2005/11/22 18:04:38 2005.14.0.2 @@ -130,6 +130,7 @@ Rule US 1976 1986 - Apr lastSun 2:00 1:0 Rule US 1987 2006 - Apr Sun>=1 2:00 1:00 D Rule US 2007 max - Mar Sun>=8 2:00 1:00 D Rule US 2007 max - Nov Sun>=1 2:00 0 S +# Keep the above rules in sync with the "US-back" rules in the "backward" file. # From Bob Devine (1988-01-28): # ...Alaska (and Hawaii) had the timezone names changed in 1967. --- Makefile 2005/07/14 18:13:37 2005.10 +++ Makefile 2005/11/22 18:07:53 2005.10.0.2 @@ -261,11 +261,10 @@ DOCS= README Theory $(MANS) date.1 Make PRIMARY_YDATA= africa antarctica asia australasia \ europe northamerica southamerica YDATA= $(PRIMARY_YDATA) pacificnew etcetera factory backward -NDATA= systemv SDATA= solar87 solar88 solar89 -TDATA= $(YDATA) $(NDATA) $(SDATA) +TDATA= $(YDATA) $(SDATA) TABDATA= iso3166.tab zone.tab -DATA= $(YDATA) $(NDATA) $(SDATA) $(TABDATA) leapseconds yearistype.sh +DATA= $(TDATA) $(TABDATA) leapseconds yearistype.sh WEB_PAGES= tz-art.htm tz-link.htm MISC= usno1988 usno1989 usno1989a usno1995 usno1997 usno1998 \ itca.jpg $(WEB_PAGES) checktab.awk workman.sh