November 1995 - tz - lists.iana.org

question regarding setting latest zone names in tzname [forwarded with permission]
by ado Nov. 20, 1995

Nov. 20, 1995

Has anybody instrumented the time zone code to determine where the sinks are? Is the area questioned below one of them? --ado > ...We have started to look at performance in this software. > I have a question that I was hoping you could answer about one piece of code > in particular in the routine settzname. It is the code filling in the > time zone name in tzname. The code fragment is: > > /* > ** And to get the latest zone names into tzname. . . > */ > for (i = 0; i < sp->timecnt; ++i) { > register const struct ttinfo * const ttisp = > > &sp->ttis[sp->types[i]]; > > tzname[ttisp->tt_isdst] = > (char *) &sp->chars[ttisp->tt_abbrind]; > } > > I am not sure why this code is looping so many times to fill in > tzname. tzname only has two fields, one for daylight savings time, > one for standard savings time, but the fields get filled in > over and over. I would really appreciate any information you have > explaining this. > > thanks in advance, > > Sandra Whitman > DEC C RTL

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tz data for Sudan
by Michael Ross Nov. 16, 1995

Nov. 16, 1995

Sudan no longer observes any form of daylight time change. I verified this today by telephone with the Sudan Mission to the United Nations: 212-573-6033 Cheers, --- Michael Ross Antigone Press, San Francisco, California e-mail: mross(a)antigone.com FAX: +1 415 550 1957 --- > > # Sudan > # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S > Rule Sudan 1931 only - Feb 8 0:00 0 - > Rule Sudan 1970 only - May 1 0:00 1:00 " DST" > Rule Sudan 1970 max - Oct 15 0:00 0 - > Rule Sudan 1971 only - Apr 30 0:00 1:00 " DST" > Rule Sudan 1972 max - Apr lastSun 0:00 1:00 " DST" > # Zone NAME GMTOFF RULES FORMAT [UNTIL] > Zone Africa/Khartoum 2:10:08 - LMT 1931 > 2:00 Sudan EET%s

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tz data for Burma
by Michael Ross Nov. 15, 1995

Nov. 15, 1995

Hello, You might want to use the offical new name: Myanmar... # Burma # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Rangoon 6:24:40 - LMT 1880 6:25 - RMT 1920 6:30 - BMT 1942 May 9:00 - JST 1945 May 3 6:30 - BMT --- Michael Ross Antigone Press, San Francisco, California e-mail: mross(a)antigone.com FAX: +1 415 550 1957 ---

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questions and comments on http://tycho.usno.navy.mil/tzones.html
by Paul Eggert Nov. 12, 1995

Nov. 12, 1995

Thanks for putting the USNO unofficial time zone info on the Web; it has helped me compose proposed patches for the public domain time zone history database at <ftp://elsie.nci.nih.gov/pub/tzdata95k.tar.gz>. After comparing the USNO data to other sources, I have some questions and comments. I'd appreciate any information you can send me to clear up the questions, especially pointers to other sources. The tzdata history database relies heavily on Thomas G. Shanks, The International Atlas (3rd edition), San Diego: ACS Publications (1991), a source that is now 4 years old, so some of the discrepancies noted below are undoubtedly because the time zones or daylight savings rules have changed recently. But I thought I'd tell you about the discrepancies just in case. <http://tycho.usno.navy.mil/tzones.html> (1995-11-11) says: Antarctica: -2 hours (Local summer -3 hours) Which part of Antarctica is that? I have the vague impression that different research stations in Antarctica use different local times. (The South Pole is the most interesting case, of course.) Armenia: +4 hours (Local summer +5 hours) Shanks has Armenia switching to +3 (+4 summer) in 1991. Perhaps they've switched back? Argentina western prov: -4 hours Shanks says Argentina has always had just one time zone. Azerbajian: +3 hours Shanks has Baku at +3 (+4 summer). Perhaps they've stopped using daylight savings time? Brazil Acre: -4 hours (Local summer -5 hours) Brazil Atlantic Islands: -1 hours (Local summer -2 hours) Brazil East: -3 hours (Local summer -1 hours) These must be typos. Here are proposed fixes. Brazil Acre: -5 hours (Local summer -4 hours) Brazil Atlantic Islands: -2 hours (Local summer -1 hours) Brazil East: -3 hours (Local summer -2 hours) Chatham Island: +12.75 hours (Local summer +13.75 hours) Do you have a source for when the transition to and from summer time takes place? Cocos (Keeling) Islands: ( hours (Local summer ) hours) This is a typo. The 1989 USNO listing has Cocos at +6.5 hours. Cook Islands: -10 hours Shanks has Cook at -9.5 during summer. The 1989 USNO listing had two entries for Cook, one at -10, the other at -10 (-9.5 summer) like Shanks. Equitorial Guinea: +1 hours This should be `Equatorial Guinea'. French Polynesia: -10 hours French Polynesia covers several time zones; e.g. I think the Marquesas and Gambier are part of French Polynesia, and they are at -9.5 and -9, respectively. Georgia: +4 hours Shanks says Georgia has summer time, but this may have changed with the rules change late last year (see _The Economist_, 1994-11-19, page 60). Is there a better source for this? Greenland Scoresbysun: -1 hours (Local summer 0 hours) This should be `Scoresbysund'. Guinea Bissau: - hours (Local summer 0 hours) This should be `0 hours', with no summer time. Kazakhstan: +6 hours (Local summer +7 hours) Shanks says Alma-Ata switched to +5 (+6 summer) in 1991. Perhaps they've switched back? Kiribati: +12 hours The country of Kiribati covers several time zones. Perhaps you could change `Kiribati' to `Tarawa'. Kwajalein: -12 hours In comp.risks 14.87 <http://catless.ncl.ac.uk/Risks/14.87.html#subj2> (1993-08-26), Peter Neumann writes that Kwajalein changed to +12 hours on 1993-08-20. Libya: +2 hours Shanks has Libya at +1 (summer +2). Mexico Baja Calif Norte: -8 hours (Local summer -7 hours) Shanks has Ensenada, southern Baja, at -8 all year. Mongolia: +8 hours Shanks says Mongolia has 3 time zones: +7 (+8 summer), +8 (+9 summer), and +9 (+10 summer). Namibia: +1 hours (Local summer +2 hours) Nicaragua: -6 hours (Local summer -5 hours) Shanks has Namibia at +2 all year, and Nicaragua at -6 all year. If these have changed recently, do you know when it changed, and what the transition times are? Russian Federation zone two: +4 hours (Local summer +5 hours) This must be a typo; it should be `+3 hours (Local summer +4 hours)'. Scotland: 0 hours Shanks and other sources have Scotland at +1 in summer. Tajikistan: +6 hours Shanks has Tajikistan at +5 (+6 summer). Perhaps they've switched? Tunisia: +1 hours Shanks has Tunisia at +2 in summer. Perhaps they've stopped using DST? Turkmenistan: +5 hours Shanks has Turkmenistan at +6 during summer. Perhaps they've stopped using DST? Ukraine: +2 hours (Local summer +3 hours) Ukraine has multiple time zones. _The Economist_ (1994-05-28, page 45) reports that Crimea switched to +3 (summer +4) last year. Uzbekistan: +5 hours Shanks has Tashkent at +5 (+6 summer). Perhaps they've stopped using daylight savings time?

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time zone sources on the Web
by Paul Eggert Nov. 6, 1995

Nov. 6, 1995

In the tz distribution, perhaps there could be an addition to README, or some new file, that lists useful Web references for time zones. Here is some possible text: The Web has several other sources for time zone and daylight savings data. Here are some recent links that may be of interest. Date and Time Gateway http://www.bsdi.com/date A text-based source for tables of current time throughout the world. Its point-and-click interface accesses a recent version of the tz data. Local Times Around the World http://www.hilink.com.au/times/ This text-based system contains links to local time servers throughout the world, and though the coverage is limited, the live data provide a nice way to check one's tables. World Time Zones http://tycho.usno.navy.mil/tzones.html US Naval Observatory data, used as the source for `usno1995'. Standard Time Zones of the World http://www.odci.gov/cia/publications/95fact/802389.gif [54 kB] http://www.odci.gov/cia/publications/95fact/802389h.gif [1317 kB] A static time zone map, available in both low-resolution and high-resolution versions. The quality is good, but the map does not indicate summer time, and parts of the data are a few years out of date. VIBE's World Map http://pathfinder.com/vibe/vibeworld An active time zone map. You can point to the map and find out what time it is at that location. The map and data are not as good as other sources.

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