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authorstefanf <stefanf@FreeBSD.org>2004-06-20 11:52:51 +0000
committerstefanf <stefanf@FreeBSD.org>2004-06-20 11:52:51 +0000
commit57534b2aa5b1f97b90aa7aca6cf42afcd44c4088 (patch)
tree481240850c1c701de114c8da4871d11c5a4d5d4e /usr.sbin/zic
parentaa456841b2ac37ef5d887fe1d9feb715d303cbee (diff)
parentac44a75e3d57edb02f32ab8cbbc19f583cb5ce8b (diff)
downloadFreeBSD-src-57534b2aa5b1f97b90aa7aca6cf42afcd44c4088.zip
FreeBSD-src-57534b2aa5b1f97b90aa7aca6cf42afcd44c4088.tar.gz
This commit was generated by cvs2svn to compensate for changes in r130777,
which included commits to RCS files with non-trunk default branches.
Diffstat (limited to 'usr.sbin/zic')
-rw-r--r--usr.sbin/zic/README20
-rw-r--r--usr.sbin/zic/Theory313
-rw-r--r--usr.sbin/zic/tz-art.htm278
-rw-r--r--usr.sbin/zic/tz-link.htm443
4 files changed, 1028 insertions, 26 deletions
diff --git a/usr.sbin/zic/README b/usr.sbin/zic/README
index 5de3d74..985a511 100644
--- a/usr.sbin/zic/README
+++ b/usr.sbin/zic/README
@@ -1,4 +1,4 @@
-@(#)README 7.10
+@(#)README 7.11
"What time is it?" -- Richard Deacon as The King
"Any time you want it to be." -- Frank Baxter as The Scientist
@@ -33,8 +33,22 @@ Since POSIX frowns on correct leap second handling, the default behavior of
the "zic" command (in the absence of a "-L" option) has been changed to omit
leap second information from its output files.
-Be sure to read the comments in "Makefile" and make any changes
-needed to make things right for your system.
+Here is a recipe for acquiring, building, installing, and testing the
+tz distribution on a GNU/Linux or similar host.
+
+ mkdir tz
+ cd tz
+ wget 'ftp://elsie.nci.nih.gov/pub/tz*.tar.gz'
+ gzip -dc tzcode*.tar.gz | tar -xf -
+ gzip -dc tzdata*.tar.gz | tar -xf -
+
+Be sure to read the comments in "Makefile" and make any changes needed
+to make things right for your system, especially if you are using some
+platform other than GNU/Linux. Then run the following commands,
+substituting your desired installation directory for "$HOME/tzdir":
+
+ make TOPDIR=$HOME/tzdir install
+ $HOME/tzdir/etc/zdump -v America/Los_Angeles
To use the new functions, use a "-ltz" option when compiling or linking.
diff --git a/usr.sbin/zic/Theory b/usr.sbin/zic/Theory
index 1c43133..cbf53b9 100644
--- a/usr.sbin/zic/Theory
+++ b/usr.sbin/zic/Theory
@@ -1,4 +1,4 @@
-@(#)Theory 7.6
+@(#)Theory 7.15
----- Outline -----
@@ -6,12 +6,14 @@
Time and date functions
Names of time zone regions
Time zone abbreviations
+ Calendrical issues
+ Time and time zones on Mars
----- Time and date functions -----
These time and date functions are upwards compatible with POSIX.1,
-an international standard for Unix-like systems.
+an international standard for UNIX-like systems.
As of this writing, the current edition of POSIX.1 is:
Information technology --Portable Operating System Interface (POSIX (R))
@@ -34,7 +36,7 @@ POSIX.1 has the following properties and limitations.
stdoffset[dst[offset],date[/time],date[/time]]
where:
-
+
std and dst
are 3 or more characters specifying the standard
and daylight saving time (DST) zone names.
@@ -143,7 +145,7 @@ Points of interest to folks with other systems:
since the format of zic's input changed slightly in late 1994,
and many vendors still do not support the new input format.
-* The Unix Version 7 "timezone" function is not present in this package;
+* The UNIX Version 7 "timezone" function is not present in this package;
it's impossible to reliably map timezone's arguments (a "minutes west
of GMT" value and a "daylight saving time in effect" flag) to a
time zone abbreviation, and we refuse to guess.
@@ -178,11 +180,34 @@ so much the better.
----- Names of time zone rule files -----
-The names of this package's installed time zone rule files are chosen to
-help minimize possible future incompatibilities due to political events.
-Ordinarily, names of countries are not used, to avoid incompatibilities
-when countries change their name (e.g. Zaire->Congo) or
-when locations change countries (e.g. Hong Kong from UK colony to China).
+The time zone rule file naming conventions attempt to strike a balance
+among the following goals:
+
+ * Uniquely identify every national region where clocks have all
+ agreed since 1970. This is essential for the intended use: static
+ clocks keeping local civil time.
+
+ * Indicate to humans as to where that region is. This simplifes use.
+
+ * Be robust in the presence of political changes. This reduces the
+ number of updates and backward-compatibility hacks. For example,
+ names of countries are ordinarily not used, to avoid
+ incompatibilities when countries change their name
+ (e.g. Zaire->Congo) or when locations change countries
+ (e.g. Hong Kong from UK colony to China).
+
+ * Be portable to a wide variety of implementations.
+ This promotes use of the technology.
+
+ * Use a consistent naming convention over the entire world.
+ This simplifies both use and maintenance.
+
+This naming convention is not intended for use by inexperienced users
+to select TZ values by themselves (though they can of course examine
+and reuse existing settings). Distributors should provide
+documentation and/or a simple selection interface that explains the
+names; see the 'tzselect' program supplied with this distribution for
+one example.
Names normally have the form AREA/LOCATION, where AREA is the name
of a continent or ocean, and LOCATION is the name of a specific
@@ -193,11 +218,16 @@ and `Pacific/Honolulu'.
Here are the general rules used for choosing location names,
in decreasing order of importance:
- Use only valid Posix file names. Use only Ascii letters, digits, `.',
- `-' and `_'. Do not exceed 14 characters or start with `-'.
- E.g. prefer `Brunei' to `Bandar_Seri_Begawan'.
+ Use only valid POSIX file name components (i.e., the parts of
+ names other than `/'). Within a file name component,
+ use only ASCII letters, `.', `-' and `_'. Do not use
+ digits, as that might create an ambiguity with POSIX
+ TZ strings. A file name component must not exceed 14
+ characters or start with `-'. E.g., prefer `Brunei'
+ to `Bandar_Seri_Begawan'.
Include at least one location per time zone rule set per country.
- One such location is enough.
+ One such location is enough. Use ISO 3166 (see the file
+ iso3166.tab) to help decide whether something is a country.
If all the clocks in a country's region have agreed since 1970,
don't bother to include more than one location
even if subregions' clocks disagreed before 1970.
@@ -209,9 +239,9 @@ in decreasing order of importance:
or regions, so that any future time zone changes do not split
locations into different time zones. E.g. prefer `Paris'
to `France', since France has had multiple time zones.
- Use traditional English spelling, e.g. prefer `Rome' to `Roma', and
+ Use mainstream English spelling, e.g. prefer `Rome' to `Roma', and
prefer `Athens' to the true name (which uses Greek letters).
- The Posix file name restrictions encourage this rule.
+ The POSIX file name restrictions encourage this rule.
Use the most populous among locations in a country's time zone,
e.g. prefer `Shanghai' to `Beijing'. Among locations with
similar populations, pick the best-known location,
@@ -225,13 +255,19 @@ in decreasing order of importance:
Use `_' to represent a space.
Omit `.' from abbreviations in names, e.g. prefer `St_Helena'
to `St._Helena'.
+ Do not change established names if they only marginally
+ violate the above rules. For example, don't change
+ the existing name `Rome' to `Milan' merely because
+ Milan's population has grown to be somewhat greater
+ than Rome's.
+ If a name is changed, put its old spelling in the `backward' file.
The file `zone.tab' lists the geographical locations used to name
time zone rule files.
Older versions of this package used a different naming scheme,
and these older names are still supported.
-See the file `backwards' for most of these older names
+See the file `backward' for most of these older names
(e.g. `US/Eastern' instead of `America/New_York').
The other old-fashioned names still supported are
`WET', `CET', `MET', `EET' (see the file `europe'),
@@ -245,25 +281,39 @@ like `EST' to be compatible with human tradition and POSIX.1.
Here are the general rules used for choosing time zone abbreviations,
in decreasing order of importance:
- Use abbreviations that consist of 3 or more upper-case Ascii letters,
- except use "___" for locations while uninhabited.
- Posix.1 requires at least 3 characters, and the restriction to
- upper-case Ascii letters follows most traditions.
+ Use abbreviations that consist of three or more ASCII letters.
Previous editions of this database also used characters like
' ' and '?', but these characters have a special meaning to
the shell and cause commands like
set `date`
- to have unexpected effects. In theory, the character set could
- be !%./@A-Z^_a-z{}, but these tables use only upper-case
- Ascii letters (and "___").
+ to have unexpected effects.
+ Previous editions of this rule required upper-case letters,
+ but the Congressman who introduced Chamorro Standard Time
+ preferred "ChST", so the rule has been relaxed.
+
+ This rule guarantees that all abbreviations could have
+ been specified by a POSIX.1 TZ string. POSIX.1
+ requires at least three characters for an
+ abbreviation. POSIX.1-1996 says that an abbreviation
+ cannot start with ':', and cannot contain ',', '-',
+ '+', NUL, or a digit. Draft 7 of POSIX 1003.1-200x
+ changes this rule to say that an abbreviation can
+ contain only '-', '+', and alphanumeric characters in
+ the current locale. To be portable to both sets of
+ rules, an abbreviation must therefore use only ASCII
+ letters, as these are the only letters that are
+ alphabetic in all locales.
+
Use abbreviations that are in common use among English-speakers,
e.g. `EST' for Eastern Standard Time in North America.
We assume that applications translate them to other languages
as part of the normal localization process; for example,
a French application might translate `EST' to `HNE'.
+
For zones whose times are taken from a city's longitude, use the
traditional xMT notation, e.g. `PMT' for Paris Mean Time.
The only name like this in current use is `GMT'.
+
If there is no common English abbreviation, abbreviate the English
translation of the usual phrase used by native speakers.
If this is not available or is a phrase mentioning the country
@@ -278,8 +328,225 @@ in decreasing order of importance:
and then append `T', `ST', etc. as before;
e.g. `VLAST' for VLAdivostok Summer Time.
+ Use "zzz" for locations while uninhabited. The mnemonic is that
+ these locations are, in some sense, asleep.
+
Application writers should note that these abbreviations are ambiguous
in practice: e.g. `EST' has a different meaning in Australia than
it does in the United States. In new applications, it's often better
to use numeric UTC offsets like `-0500' instead of time zone
abbreviations like `EST'; this avoids the ambiguity.
+
+
+----- Calendrical issues -----
+
+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,
+<a href="http://emr.cs.uiuc.edu/home/reingold/calendar-book/index.shtml">
+Calendrical Calculations
+</a>, Cambridge University Press (1997). Other information and
+sources are given below. They sometimes disagree.
+
+
+France
+
+Gregorian calendar adopted 1582-12-20.
+French Revolutionary calendar used 1793-11-24 through 1805-12-31,
+and (in Paris only) 1871-05-06 through 1871-05-23.
+
+
+Russia
+
+From Chris Carrier <72157.3334@CompuServe.COM> (1996-12-02):
+On 1929-10-01 the Soviet Union instituted an ``Eternal Calendar''
+with 30-day months plus 5 holidays, with a 5-day week.
+On 1931-12-01 it changed to a 6-day week; in 1934 it reverted to the
+Gregorian calendar while retaining the 6-day week; on 1940-06-27 it
+reverted to the 7-day week. With the 6-day week the usual days
+off were the 6th, 12th, 18th, 24th and 30th of the month.
+(Source: Evitiar Zerubavel, _The Seven Day Circle_)
+
+
+Mark Brader reported a similar story in "The Book of Calendars", edited
+by Frank Parise (1982, Facts on File, ISBN 0-8719-6467-8), page 377. But:
+
+From: Petteri Sulonen (via Usenet)
+Date: 14 Jan 1999 00:00:00 GMT
+Message-ID: <Petteri.Sulonen-1401991626030001@lapin-kulta.in.helsinki.fi>
+
+If your source is correct, how come documents between 1929 -- 1940 were
+still dated using the conventional, Gregorian calendar?
+
+I can post a scan of a document dated December 1, 1934, signed by
+Yenukidze, the secretary, on behalf of Kalinin, the President of the
+Executive Committee of the Supreme Soviet, if you like.
+
+
+
+Sweden (and Finland)
+
+From: msb@sq.com (Mark Brader)
+<a href="news:1996Jul6.012937.29190@sq.com">
+Subject: Re: Gregorian reform -- a part of locale?
+</a>
+Date: 1996-07-06
+
+In 1700, Denmark made the transition from Julian to Gregorian. Sweden
+decided to *start* a transition in 1700 as well, but rather than have one of
+those unsightly calendar gaps :-), they simply decreed that the next leap
+year after 1696 would be in 1744 -- putting the whole country on a calendar
+different from both Julian and Gregorian for a period of 40 years.
+
+However, in 1704 something went wrong and the plan was not carried through;
+they did, after all, have a leap year that year. And one in 1708. In 1712
+they gave it up and went back to Julian, putting 30 days in February that
+year!...
+
+Then in 1753, Sweden made the transition to Gregorian in the usual manner,
+getting there only 13 years behind the original schedule.
+
+(A previous posting of this story was challenged, and Swedish readers
+produced the following references to support it: "Tiderakning och historia"
+by Natanael Beckman (1924) and "Tid, en bok om tiderakning och
+kalendervasen" by Lars-Olof Lode'n (no date was given).)
+
+
+Grotefend's data
+
+From: "Michael Palmer" <mpalmer@netcom.com> [with one obvious typo fixed]
+Subject: Re: Gregorian Calendar (was Re: Another FHC related question
+Newsgroups: soc.genealogy.german
+Date: Tue, 9 Feb 1999 02:32:48 -800
+Message-ID: <199902091032.CAA09644@netcom10.netcom.com>
+
+The following is a(n incomplete) listing, arranged chronologically, of
+European states, with the date they converted from the Julian to the
+Gregorian calendar:
+
+04/15 Oct 1582 - Italy (with exceptions), Spain, Portugal, Poland (Roman
+ Catholics and Danzig only)
+09/20 Dec 1582 - France, Lorraine
+
+21 Dec 1582/
+ 01 Jan 1583 - Holland, Brabant, Flanders, Hennegau
+10/21 Feb 1583 - bishopric of Liege (L"uttich)
+13/24 Feb 1583 - bishopric of Augsburg
+04/15 Oct 1583 - electorate of Trier
+05/16 Oct 1583 - Bavaria, bishoprics of Freising, Eichstedt, Regensburg,
+ Salzburg, Brixen
+13/24 Oct 1583 - Austrian Oberelsass and Breisgau
+20/31 Oct 1583 - bishopric of Basel
+02/13 Nov 1583 - duchy of J"ulich-Berg
+02/13 Nov 1583 - electorate and city of K"oln
+04/15 Nov 1583 - bishopric of W"urzburg
+11/22 Nov 1583 - electorate of Mainz
+16/27 Nov 1583 - bishopric of Strassburg and the margraviate of Baden
+17/28 Nov 1583 - bishopric of M"unster and duchy of Cleve
+14/25 Dec 1583 - Steiermark
+
+06/17 Jan 1584 - Austria and Bohemia
+11/22 Jan 1584 - Luzern, Uri, Schwyz, Zug, Freiburg, Solothurn
+12/23 Jan 1584 - Silesia and the Lausitz
+22 Jan/
+ 02 Feb 1584 - Hungary (legally on 21 Oct 1587)
+ Jun 1584 - Unterwalden
+01/12 Jul 1584 - duchy of Westfalen
+
+16/27 Jun 1585 - bishopric of Paderborn
+
+14/25 Dec 1590 - Transylvania
+
+22 Aug/
+ 02 Sep 1612 - duchy of Prussia
+
+13/24 Dec 1614 - Pfalz-Neuburg
+
+ 1617 - duchy of Kurland (reverted to the Julian calendar in
+ 1796)
+
+ 1624 - bishopric of Osnabr"uck
+
+ 1630 - bishopric of Minden
+
+15/26 Mar 1631 - bishopric of Hildesheim
+
+ 1655 - Kanton Wallis
+
+05/16 Feb 1682 - city of Strassburg
+
+18 Feb/
+ 01 Mar 1700 - Protestant Germany (including Swedish possessions in
+ Germany), Denmark, Norway
+30 Jun/
+ 12 Jul 1700 - Gelderland, Zutphen
+10 Nov/
+ 12 Dec 1700 - Utrecht, Overijssel
+
+31 Dec 1700/
+ 12 Jan 1701 - Friesland, Groningen, Z"urich, Bern, Basel, Geneva,
+ Turgau, and Schaffhausen
+
+ 1724 - Glarus, Appenzell, and the city of St. Gallen
+
+01 Jan 1750 - Pisa and Florence
+
+02/14 Sep 1752 - Great Britain
+
+17 Feb/
+ 01 Mar 1753 - Sweden
+
+1760-1812 - Graub"unden
+
+The Russian empire (including Finland and the Baltic states) did not
+convert to the Gregorian calendar until the Soviet revolution of 1917.
+
+Source: H. Grotefend, _Taschenbuch der Zeitrechnung des deutschen
+Mittelalters und der Neuzeit_, herausgegeben von Dr. O. Grotefend
+(Hannover: Hahnsche Buchhandlung, 1941), pp. 26-28.
+
+
+----- Time and time zones on Mars -----
+
+Some people have adjusted their work schedules to fit Mars time.
+Dozens of special Mars watches were built for Jet Propulsion
+Laboratory workers who kept Mars time during the Mars Exploration
+Rovers mission (2004). These timepieces look like normal Seikos and
+Citizens but use Mars seconds rather than terrestrial seconds.
+
+A Mars solar day is called a "sol" and has a mean period equal to
+about 24 hours 39 minutes 35.244 seconds in terrestrial time. It is
+divided into a conventional 24-hour clock, so each Mars second equals
+about 1.02749125 terrestrial seconds.
+
+The prime meridian of Mars goes through the center of the crater
+Airy-0, named in honor of the British astronomer who built the
+Greenwich telescope that defines Earth's prime meridian. Mean solar
+time on the Mars prime meridian is called Mars Coordinated Time (MTC).
+
+Each landed mission on Mars has adopted a different reference for
+solar time keeping, so there is no real standard for Mars time zones.
+For example, the Mars Exploration Rover project (2004) defined two
+time zones "Local Solar Time A" and "Local Solar Time B" for its two
+missions, each zone designed so that its time equals local true solar
+time at approximately the middle of the nominal mission. Such a "time
+zone" is not particularly suited for any application other than the
+mission itself.
+
+Many calendars have been proposed for Mars, but none have achieved
+wide acceptance. Astronomers often use Mars Sol Date (MSD) which is a
+sequential count of Mars solar days elapsed since about 1873-12-29
+12:00 GMT.
+
+The tz database does not currently support Mars time, but it is
+documented here in the hopes that support will be added eventually.
+
+Sources:
+
+Michael Allison and Robert Schmunk,
+"Technical Notes on Mars Solar Time as Adopted by the Mars24 Sunclock"
+<http://www.giss.nasa.gov/tools/mars24/help/notes.html> (2004-03-15).
+
+Jia-Rui Chong, "Workdays Fit for a Martian", Los Angeles Times
+(2004-01-14), pp A1, A20-A21.
diff --git a/usr.sbin/zic/tz-art.htm b/usr.sbin/zic/tz-art.htm
new file mode 100644
index 0000000..56f78ac
--- /dev/null
+++ b/usr.sbin/zic/tz-art.htm
@@ -0,0 +1,278 @@
+<?xml version="1.0" encoding="US-ASCII"?>
+<!DOCTYPE html
+PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+"DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+<head>
+<meta http-equiv="Content-type" content='text/html; charset="US-ASCII"' />
+<title>Time and the Arts</title>
+</head>
+<body>
+<h1>Time and the Arts</h1>
+<address>
+@(#)tz-art.htm 7.53
+</address>
+<p>
+Please send corrections to this web page to the
+<a href="mailto:tz@elsie.nci.nih.gov">time zone mailing list</a>.</p>
+<p>
+See also <a href="tz-link.htm">Sources for Time Zone and Daylight Saving Time Data</a>.</p>
+<hr />
+<p>
+Data on recordings of "Save That Time," Russ Long, Serrob Publishing, BMI:</p>
+<table>
+<tr><td>Artist</td><td>Karrin Allyson</td></tr>
+<tr><td>CD</td><td>I Didn't Know About You</td></tr>
+<tr><td>Copyright Date</td><td>1993</td></tr>
+<tr><td>Label</td><td>Concord Jazz, Inc.</td></tr>
+<tr><td>ID</td><td>CCD-4543</td></tr>
+<tr><td>Track Time</td><td>3:44</td></tr>
+<tr><td>Personnel</td><td>Karrin Allyson, vocal;
+Russ Long, piano;
+Gerald Spaits, bass;
+Todd Strait, drums</td></tr>
+<tr><td>Notes</td><td>CD notes "additional lyric by Karrin Allyson;
+arranged by Russ Long and Karrin Allyson"</td></tr>
+<tr><td>ADO Rating</td><td>1 star</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=A1fdovw9ta92k">AMG Rating</a></td><td>4 stars</td></tr>
+<tr><td>Penguin Rating</td><td>3.5 stars</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Kevin Mahogany</td></tr>
+<tr><td>CD</td><td>Double Rainbow</td></tr>
+<tr><td>Copyright Date</td><td>1993</td></tr>
+<tr><td>Label</td><td>Enja Records</td></tr>
+<tr><td>ID</td><td>ENJ-7097 2</td></tr>
+<tr><td>Track Time</td><td>6:27</td></tr>
+<tr><td>Personnel</td><td>Kevin Mahogany, vocal;
+Kenny Barron, piano;
+Ray Drummond, bass;
+Ralph Moore, tenor saxophone;
+Lewis Nash, drums</td></tr>
+<tr><td>ADO Rating</td><td>1.5 stars</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=Akikbikzjbb19">AMG Rating</a></td><td>3 stars</td></tr>
+<tr><td>Penguin Rating</td><td>3 stars</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Joe Williams</td></tr>
+<tr><td>CD</td><td>Here's to Life</td></tr>
+<tr><td>Copyright Date</td><td>1994</td></tr>
+<tr><td>Label</td><td>Telarc International Corporation</td></tr>
+<tr><td>ID</td><td>CD-83357</td></tr>
+<tr><td>Track Time</td><td>3:58</td></tr>
+<tr><td>Personnel</td><td>Joe Williams, vocal
+The Robert Farnon [39 piece] Orchestra</td></tr>
+<tr><td>Notes</td><td>This CD is also available as part of a 3-CD package from
+Telarc, "Triple Play" (CD-83461)</td></tr>
+<tr><td>ADO Rating</td><td>black dot</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=Amyyvad6kt8w1">AMG Rating</a></td><td>2 stars</td></tr>
+<tr><td>Penguin Rating</td><td>3 stars</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Charles Fambrough</td></tr>
+<tr><td>CD</td><td>Keeper of the Spirit</td></tr>
+<tr><td>Copyright Date</td><td>1995</td></tr>
+<tr><td>Label</td><td>AudioQuest Music</td></tr>
+<tr><td>ID</td><td>AQ-CD1033</td></tr>
+<tr><td>Track Time</td><td>7:07</td></tr>
+<tr><td>Personnel</td><td>Charles Fambrough, bass;
+Joel Levine, tenor recorder;
+Edward Simon, piano;
+Lenny White, drums;
+Marion Simon, percussion</td></tr>
+<tr><td>Notes</td><td>On-line information and samples available at
+<a href="http://wwmusic.com/~music/audioq/rel/1033.html">http://wwmusic.com/~music/audioq/rel/1033.html</a></td></tr>
+<tr><td>ADO Rating</td><td>2 stars</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=A5rkcikcjbb89">AMG Rating</a></td><td>unrated</td></tr>
+<tr><td>Penguin Rating</td><td>3 stars</td></tr>
+</table>
+<hr />
+<p>Also of note:</p>
+<table>
+<tr><td>Artist</td><td>Holly Cole Trio</td></tr>
+<tr><td>CD</td><td>Blame It On My Youth</td></tr>
+<tr><td>Copyright Date</td><td>1992</td></tr>
+<tr><td>Label</td><td>Manhattan</td></tr>
+<tr><td>ID</td><td>CDP 7 97349 2</td></tr>
+<tr><td>Total Time</td><td>37:45</td></tr>
+<tr><td>Personnel</td><td>Holly Cole, voice;
+Aaron Davis, piano;
+David Piltch, string bass</td></tr>
+<tr><td>Notes</td><td>Lyrical reference to "Eastern Standard Time" in
+Tom Waits' "Purple Avenue"</td></tr>
+<tr><td>ADO Rating</td><td>2.5 stars</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=A3a9ds37ya3dg">AMG Rating</a></td><td>3 stars</td></tr>
+<tr><td>Penguin Rating</td><td>unrated</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Milt Hinton</td></tr>
+<tr><td>CD</td><td>Old Man Time</td></tr>
+<tr><td>Copyright Date</td><td>1990</td></tr>
+<tr><td>Label</td><td>Chiaroscuro</td></tr>
+<tr><td>ID</td><td>CR(D) 310</td></tr>
+<tr><td>Total Time</td><td>149:38 (two CDs)</td></tr>
+<tr><td>Personnel</td><td>Milt Hinton, bass;
+Doc Cheatham, Dizzy Gillespie, Clark Terry, trumpet;
+Al Grey, trombone;
+Eddie Barefield, Joe Camel (Flip Phillips), Buddy Tate,
+clarinet and saxophone;
+John Bunch, Red Richards, Norman Simmons, Derek Smith,
+Ralph Sutton, piano;
+Danny Barker, Al Casey, guitar;
+Gus Johnson, Gerryck King, Bob Rosengarden, Jackie Williams,
+drums;
+Lionel Hampton, vibraphone;
+Cab Calloway, Joe Williams, vocal;
+Buck Clayton, arrangements</td></tr>
+<tr><td>Notes</td><td>tunes include Old Man Time, Time After Time,
+Sometimes I'm Happy,
+A Hot Time in the Old Town Tonight,
+Four or Five Times, Now's the Time,
+Time on My Hands, This Time It's Us,
+and Good Time Charlie
+On-line samples available at
+<a href="http://www.chiaroscurojazz.com/albuminfo.php4?albumid=49">http://www.chiaroscurojazz.com/albuminfo.php3?albumid=49</a></td></tr>
+<tr><td>ADO Rating</td><td>3 stars</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=A1cbyxdab8ola">AMG Rating</a></td><td>4.5 stars</td></tr>
+<tr><td>Penguin Rating</td><td>3 stars</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Alan Broadbent</td></tr>
+<tr><td>CD</td><td>Pacific Standard Time</td></tr>
+<tr><td>Copyright Date</td><td>1995</td></tr>
+<tr><td>Label</td><td>Concord Jazz, Inc.</td></tr>
+<tr><td>ID</td><td>CCD-4664</td></tr>
+<tr><td>Total Time</td><td>62:42</td></tr>
+<tr><td>Personnel</td><td>Alan Broadbent, piano;
+Putter Smith, Bass;
+Frank Gibson, Jr., drums</td></tr>
+<tr><td>Notes</td><td>The CD cover features an analemma for equation-of-time fans</td></tr>
+<tr><td>ADO Rating</td><td>1 star</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=Asl8zefuk8gfo">AMG Rating</a></td><td>4 stars</td></tr>
+<tr><td>Penguin Rating</td><td>3.5 stars</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Anthony Braxton/Richard Teitelbaum</td></tr>
+<tr><td>CD</td><td>Silence/Time Zones</td></tr>
+<tr><td>Copyright Date</td><td>1996</td></tr>
+<tr><td>Label</td><td>Black Lion</td></tr>
+<tr><td>ID</td><td>BLCD 760221</td></tr>
+<tr><td>Total Time</td><td>72:58</td></tr>
+<tr><td>Personnel</td><td>Anthony Braxton, sopranino and alto saxophones,
+contrebasse clarinet, miscellaneous instruments;
+Leo Smith, trumpet and miscellaneous instruments;
+Leroy Jenkins, violin and miscellaneous instruments;
+Richard Teitelbaum, modular moog and micromoog synthesizer</td></tr>
+<tr><td>ADO Rating</td><td>black dot</td></tr>
+<tr><td><a href="http://www.allmusic.com/cg/amg.dll?p=amg&amp;sql=A5bkvu3xjan1k">AMG Rating</a></td><td>unrated</td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Artist</td><td>Jules Verne</td></tr>
+<tr><td>Book</td><td>Le Tour du Monde en Quatre-Vingts Jours
+(Around the World in Eighty Days)</td></tr>
+<tr><td>Notes</td><td>Wall-clock time plays a central role in the plot.
+European readers of the 1870s clearly held the U.S. press in
+deep contempt; the protagonists cross the U.S. without once
+reading a paper.
+An on-line French-language version of the book
+"with illustrations from the original 1873 French-language edition"
+is available at
+<a href="http://fourmilab.ch/etexts/www/tdm80j">http://fourmilab.ch/etexts/www/tdm80j</a>
+An on-line English-language translation of the book is available at
+<a href="http://www.literature.org/Works/Jules-Verne/eighty">http://www.literature.org/Works/Jules-Verne/eighty</a></td></tr>
+<tr><td>&nbsp;</td></tr>
+<tr><td>Film</td><td>Bell Science - About Time</td></tr>
+<tr><td>Notes</td><td>The Frank Baxter/Richard Deacon extravaganza
+Information on ordering is available at
+<a href="http://www.videoflicks.com/VF2/1035/1035893.ihtml">http://www.videoflicks.com/VF2/1035/1035893.ihtml</a></td></tr>
+</table>
+<hr />
+<ul>
+<li>
+An episode of "The Adventures of Superman" entitled "The Mysterious
+Cube," first aired 1958-02-24, had Superman convincing the controllers
+of WWV to broadcast time signals five minutes ahead of actual time;
+doing so got a crook trying to beat the statute of limitations to
+emerge a bit too early from the titular enclosure.
+</li>
+<li>
+The 1960s ITC television series "The Prisoner" included an episode
+entitled "The Chimes of Big Ben" in which our protagonist tumbled to
+the fraudulent nature of a Poland-to-England escape upon hearing "Big
+Ben" chiming on Polish local time.
+</li>
+<li>
+The series "Seinfeld" included an episode entitled "The Susie," first
+broadcast 1997-02-13, in which Kramer decides that daylight saving time
+isn't coming fast enough, so he sets his watch ahead an hour.
+</li>
+<li>
+The syndicated comic strip "Dilbert" featured an all-too-rare example of
+time zone humor on 1998-03-14.
+</li>
+<li>
+Surrealist artist Guy Billout's work "Date Line" appeared on page 103
+of the 1999-11 Atlantic Monthly.
+</li>
+<li>
+"Gloom, Gloom, Go Away" by Walter Kirn appeared on page 106 of Time
+Magazine's 2002-11-11 issue; among other things, it proposed
+year-round DST as a way of lessening wintertime despair.
+</li>
+<li>
+The "20 Hours in America" episode of "The West Wing," first aired 2002-09-25,
+saw White House staffers stranded in Indiana; they thought they had time to
+catch Air Force One but were done in by intra-Indiana local time changes.
+</li>
+<li>
+"In what time zone would you find New York City?" was a $200 question on
+the 1999-11-13 United States airing of "Who Wants to Be a Millionaire?"
+"In 1883, what industry led the movement to divide the U.S. into four time
+zones?" was a $32,000 question on the 2001-05-23 United States airing of
+"Who Wants to Be a Millionaire?" At this rate, the million-dollar time-zone
+question should have been asked 2002-06-04.
+</li>
+</ul>
+<hr />
+<ul>
+<li>
+"We're been using the five-cent nickle in this country since 1492.
+Now that's pretty near 100 years, daylight savings [sic]."
+(Groucho Marx as Captain Spaulding in "Animal Crackers", 1930,
+as noted by Will Fitzerald, wfitzgerald@ameritech.net)
+</li>
+<li>
+"Good news."
+"What did they do? Extend Daylight Saving Time year round?"
+(Professional tanner George Hamilton, in dialog from a
+May, 1999 episode of the syndicated television series "Baywatch")
+</li>
+<li>
+"A fundamental belief held by Americans is that if you are on land, you
+cannot be killed by a fish...So most Americans remain on land, believing
+they're safe. Unfortunately, this belief&mdash;like so many myths, such as that
+there's a reason for 'Daylight Saving Time'&mdash;is false."
+(Dave Barry column, 2000-07-02)
+</li>
+<li>
+"I once had sex for an hour and five minutes, but that was on the day
+when you turn the clocks ahead."
+(Garry Shandling, 52nd Annual Emmys, 2000-09-10)
+</li>
+<li>
+"Would it impress you if I told you I invented Daylight Savings Time?"
+("Sahjhan" to "Lilah" in dialog from the "Loyalty" episode of "Angel,"
+originally aired 2002-02-25)
+</li>
+<li>
+"I thought you said Tulsa was a three hour flight."
+"Well, you're forgetting about the time difference."
+("Chandler" and "Joey" in dialog from the episode of "Friends" first
+aired 2002-12-05)
+</li>
+<li>
+"Is that a pertinent fact,
+or are you trying to dazzle me with your command of time zones?"
+(Kelsey Grammer as "Frasier Crane")
+</li>
+<li>
+"Don't worry about the world coming to an end today.
+It is already tomorrow in Australia."
+(Charles M. Schulz, provided by Steve Summit)
+</li>
+</ul>
+</body>
+</html>
diff --git a/usr.sbin/zic/tz-link.htm b/usr.sbin/zic/tz-link.htm
new file mode 100644
index 0000000..0e63073
--- /dev/null
+++ b/usr.sbin/zic/tz-link.htm
@@ -0,0 +1,443 @@
+<?xml version="1.0" encoding="US-ASCII"?>
+<!DOCTYPE html
+ PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+ "DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
+<head>
+<title>Sources for Time Zone and Daylight Saving Time Data</title>
+<link rel="schema.DC" href="http://purl.org/DC/elements/1.1/" />
+<meta http-equiv="Content-type" content='text/html; charset="US-ASCII"' />
+<meta name="DC.Creator" content="Eggert, Paul" />
+<meta name="DC.Contributor" content="Olson, Arthur David" />
+<meta name="DC.Date" content="2004-05-24" />
+<meta name="DC.Description"
+ content="Sources of information about time zones and daylight saving time" />
+<meta name="DC.Identifier" content="http://www.twinsun.com/tz/tz-link.htm" />
+<meta name="Keywords"
+ content="database,daylight saving,DST,time zone,timezone,tz,zoneinfo" />
+</head>
+<body>
+<h1>Sources for Time Zone and Daylight Saving Time Data</h1>
+<address>
+@(#)tz-link.htm 7.42
+</address>
+<p>
+Please send corrections to this web page to the
+<a href="mailto:tz@elsie.nci.nih.gov">time zone mailing list</a>.
+</p>
+<h2>The <code>tz</code> database</h2>
+<p>
+The public-domain 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 UTC offsets and daylight-saving rules.
+This database (often called <code>tz</code> or <code>zoneinfo</code>)
+is used by several implementations,
+including
+<a href="http://www.gnu.org/software/libc/">the GNU C Library</a> used in
+<a href="http://www.linux.org/">GNU/Linux</a>,
+<a href="http://www.freebsd.org/">FreeBSD</a>,
+<a href="http://www.netbsd.org/">NetBSD</a>,
+<a href="http://www.openbsd.org/">OpenBSD</a>,
+<a href="http://www.cygwin.com/">Cygwin</a>,
+<a href="http://www.delorie.com/djgpp/">DJGPP</a>,
+<a href="http://www.hp.com/products1/unix/operating/">HP-UX</a>,
+<a href="http://www.sgi.com/developers/technology/irix/">IRIX</a>,
+<a href="http://www.apple.com/macosx/">Mac OS X</a>,
+<a href="http://h71000.www7.hp.com/">OpenVMS</a>,
+<a href="http://wwws.sun.com/software/solaris/">Solaris</a>,
+<a href="http://www.tru64unix.compaq.com/">Tru64</a>, and
+<a href="http://www.sco.com/products/unixware/">UnixWare</a>.</p>
+<p>
+Each location in the database represents a national region where all
+clocks keeping local time have agreed since 1970.
+Locations are identified by continent or ocean and then by the name of
+the location, which is typically the largest city within the region.
+For example, <code>America/New_York</code>
+represents most of the US eastern time zone;
+<code>America/Indianapolis</code> represents most of Indiana, which
+uses eastern time without daylight saving time (DST);
+<code>America/Detroit</code> represents most of Michigan, which uses
+eastern time but with different DST rules in 1975;
+and other entries represent smaller regions like Starke County,
+Kentucky, which switched from central to eastern time in 1991.
+To use the database, set the <code>TZ</code> environment variable to
+the location's full name, e.g., <code>TZ="America/New_York"</code>.</p>
+<p>
+In the <code>tz</code> database's
+<a href="ftp://elsie.nci.nih.gov/pub/">FTP distribution</a>,
+the code is in the file <code>tzcode<var>C</var>.tar.gz</code>,
+where <code><var>C</var></code> is the code's version;
+similarly, the data are in <code>tzdata<var>D</var>.tar.gz</code>,
+where <code><var>D</var></code> is the data's version.
+The following shell commands download
+these files to a GNU/Linux or similar host; see the downloaded
+<code>README</code> file for what to do next.</p>
+<pre style="margin-left: 2em"><code><a href="http://www.gnu.org/software/wget/">wget</a> 'ftp://elsie.nci.nih.gov/pub/tz*.tar.gz'
+<a href="http://www.gnu.org/software/gzip/">gzip</a> -dc tzcode*.tar.gz | <a href="http://www.gnu.org/software/tar/">tar</a> -xf -
+gzip -dc tzdata*.tar.gz | tar -xf -
+</code></pre>
+<p>
+The code lets you compile the <code>tz</code> source files into
+machine-readable binary files, one for each location. It also lets
+you read a <code>tz</code> binary file and interpret time stamps for that
+location.</p>
+<p>
+The data are by no means authoritative. If you find errors, please
+send changes to the <a href="mailto:tz@elsie.nci.nih.gov">time zone
+mailing list</a>. You can also <a
+href="mailto:tz-request@elsie.nci.nih.gov">subscribe</a> to the
+mailing list, retrieve the <a
+href="ftp://elsie.nci.nih.gov/pub/tzarchive.gz">archive of old
+messages</a> (in gzip compressed format), or retrieve <a
+href="ftp://munnari.oz.au/pub/oldtz/">archived older versions of code
+and data</a>.</p>
+<p>
+The Web has several other sources for time zone and daylight saving time data.
+Here are some recent links that may be of interest.
+</p>
+<h2>Web pages using recent versions of the <code>tz</code> database</h2>
+<ul>
+<li><a href="http://twiki.org/cgi-bin/xtra/tzdate">Date and Time Gateway</a>
+is a text-based point-and-click interface to tables of current time
+throughout the world.</li>
+<li>Fancier web interfaces, roughly in ascending order of complexity, include:
+<ul>
+<li><a href="http://www.hilink.com.au/times/">Local Times Around the
+World</a></li>
+<li><a href="http://www.convertit.com/Go/ConvertIt/World_Time/Current_Time.ASP">Current Time in 1000 Places</a></li>
+<li><a href="http://timezoneconverter.com/">Time Zone Converter</a></li>
+</ul></li>
+<li><a href="http://www.holidayfestival.com/">The Worldwide Holiday
+&amp; Festival Site</a> lists DST-related clock changes along with
+holidays.</li>
+<li><a href="http://www.timeanddate.com/worldclock/">The World Clock -
+Time Zones</a>
+is a web interface to a time zone database derived from
+<code>tz</code>'s.</li>
+</ul>
+<h2>Other time zone database formats</h2>
+<ul>
+<li>The <a href="ftp://ftp.rfc-editor.org/in-notes/rfc2445.txt">
+Internet Calendaring and Scheduling Core Object Specification
+(iCalendar)</a> specification published by the <a
+href="http://www.ietf.org/html.charters/calsch-charter.html">IETF
+Calendaring and Scheduling Working Group (calsch)</a> covers time zone
+data; see its VTIMEZONE calendar component.</li>
+<li>The <a
+href="http://lists.w3.org/Archives/Public/www-rdf-calendar/">www-rdf-calendar</a>
+list discusses <a href="http://www.w3.org/RDF/">RDF</a>-based calendar
+and group scheduling systems, and has a <a
+href="http://www.w3.org/2002/12/cal/#tzd">workspace on time zone
+data</a> converted from <code>tz</code>. An earlier <a
+href="http://www.w3.org/2000/01/foo">schema</a> was sketched out by <a
+href="http://www.w3.org/People/Berners-Lee/">Tim Berners-Lee</a>.</li>
+<li><a
+href="http://www.calsch.org/ietf/archives/draft-ietf-calsch-many-xcal-02.txt">XCal</a>
+was a draft <a href="http://www.w3.org/XML/">XML</a> document type
+definition that corresponded to iCalendar.</li>
+</ul>
+<h2>Other <code>tz</code> compilers</h2>
+<ul>
+<li><a href="http://www.dachaplin.dsl.pipex.com/vzic">Vzic iCalendar
+Timezone Converter</a> describes a program Vzic that compiles
+<code>tz</code> source into iCalendar-compatible VTIMEZONE files.
+Vzic is freely
+available under the <a href="http://www.gnu.org/copyleft/gpl.html">GNU
+General Public License (GPL)</a>.</li>
+<li><a
+href="http://search.cpan.org/dist/DateTime-TimeZone/">DateTime::TimeZone</a>
+contains a script <code>parse_olson</code> that compiles
+<code>tz</code> source into <a href="http://www.perl.org/">Perl</a>
+modules. It is part of the Perl <a
+href="http://datetime.perl.org/">DateTime Project</a>, which is freely
+available under both the GPL and the Perl <a
+href="http://www.perl.com/language/misc/Artistic.html">Artistic
+License</a>. DateTime::TimeZone also contains a script
+<code>tests_from_zdump</code> that generates test cases for each clock
+transition in the <code>tz</code> database.</li>
+<li><a href="http://oss.software.ibm.com/icu/">International Components for
+Unicode (ICU)</a> contains a C/C++ library for internationalization that
+has a compiler from <samp>tz</samp> source into an ICU-specific format.
+ICU is freely available under a BSD-style license.</li>
+<li><a href="http://joda-time.sourceforge.net/">Joda Time - Java date
+and time API</a> contains a class
+<code>org.joda.time.tz.ZoneInfoCompiler</code> that compiles
+<code>tz</code> source into a Joda-specific binary format. Joda Time
+is freely available under a BSD-style license.</li>
+</ul>
+<h2>Other <code>tz</code> binary file readers</h2>
+<ul>
+<li>The <a href="http://www.gnu.org/software/libc/">GNU C Library</a>
+has an independent, thread-safe implementation of
+a <code>tz</code> binary file reader.
+This library is freely available under the
+<a href="http://www.gnu.org/copyleft/lesser.html">
+GNU Lesser General Public License (LGPL)</a>,
+and is widely used in GNU/Linux systems.</li>
+<li><a href="http://www.bmsi.com/java/#TZ">ZoneInfo.java</a>
+is a <code>tz</code> binary file reader written in Java.
+It is freely available under the GNU LGPL.</li>
+<li><a href="http://s.keim.free.fr/tz/doc.html">Python time zones</a>
+is a <code>tz</code> binary file reader written in <a
+href="http://www.python.org/">Python</a>. It is freely available
+under a BSD-style license.</li>
+</ul>
+<h2>Other <code>tz</code>-based time zone conversion software</h2>
+<ul>
+<li><a href="http://java.sun.com/">Sun Java</a> releases since 1.4
+contain a copy of a recent <samp>tz</samp> database in a Java-specific
+format.</li>
+<li><a
+href="http://www1.tip.nl/~t876506/AboutTimeZonesHC.html">HyperCard
+time zones calculator</a> is a HyperCard stack.</li>
+<li><a
+href="http://www.cimmyt.org/timezone/">World Time Explorer</a> is a
+Microsoft Windows program.</li>
+</ul>
+<h2>Other time zone databases</h2>
+<ul>
+<li><a href="http://www.astro.com/cgi-bin/atlw3/aq.cgi?lang=e">Atlas Query
+- Astrodienst</a> is Astrodienst's Web version of Shanks's
+excellent time zone history atlases published in both <a
+href="http://astrocom.com/software/pcatlas.php">computer</a> and <a
+href="http://astrocom.com/books/xrefa.php#SHANKS">book</a> form by <a
+href="http://astrocom.com/">Astro Communications Services</a>.</li>
+<li><a href="http://worldtime.com/">WORLDTIME: interactive atlas,
+time info, public holidays</a>
+contains information on local time, sunrise and sunset,
+and public holidays in several hundred cities around the world.</li>
+<li><a href="http://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 US Naval Observatory
+(USNO), used as the source
+for the <code>usno*</code> files in the <code>tz</code> distribution.</li>
+<li><a href="http://www.airportcitycodes.com/aaa/">Airlines, Airplanes
+and Airports</a> lists current standard times for thousands of
+airports around the world. This seems to be derived from
+the <a href="http://www.iata.org/sked/publications/">Standard
+Schedules Information Manual (SSIM)</a> of the
+the <a href="http://www.iata.org/">International Air Transport
+Association</a>,
+which gives current time zone rules for
+all the airports served by commercial aviation.</li>
+</ul>
+<h2>Maps</h2>
+<ul>
+<li>The <a href="http://www.odci.gov/">United States Central
+Intelligence Agency (CIA)</a> publishes a <a
+href="http://www.odci.gov/cia/publications/factbook/reference_maps/pdf/time_zones.pdf">time
+zone map</a>; the
+<a
+href="http://www.lib.utexas.edu/maps/world.html">Perry-Casta&ntilde;eda
+Library Map Collection</a>
+of the University of Texas at Austin has copies of
+recent editions.
+The pictorial quality is good,
+but the maps do not indicate summer time,
+and parts of the data are a few years out of date.</li>
+<li><a href="http://worldtimezone.com/">World timezones map with
+current time</a>
+has several fancy time zone maps; it covers Russia particularly well.
+The maps' pictorial quality is not quite as good as the CIA's
+but the maps are more up to date.</li>
+</ul>
+<h2>Time zone boundaries</h2>
+<ul>
+<li><a href="http://home-4.tiscali.nl/~t876506/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://www.manifold.net/download/freemaps.html">Free Maps and
+GIS Data</a> includes a Manifold-format map of world time zone
+boundaries distributed under the GPL. The GeoCommunity's <a
+href="http://software.geocomm.com/data/intl_timezones.html">International
+Time Zones</a> publishes the same data in other formats.</li>
+<li>The US Geological Survey's National Atlas of the United States
+publishes the <a href="http://www.nationalatlas.gov/timeznm.html">Time
+Zones of the United States</a> in the public domain.</li>
+<li>The GeoCommunity lists several commercial sources for <a
+href="http://spatialnews.geocomm.com/features/timezones/">International
+Time Zones and Time Zone Data</a>.</li>
+</ul>
+<h2>Civil time concepts and history</h2>
+<ul>
+<li><a href="http://physics.nist.gov/time">A Walk through Time</a>
+surveys the evolution of timekeeping.</li>
+<li><a href="http://webexhibits.org/daylightsaving/">About Daylight
+Saving Time - History, rationale, laws and dates</a>
+is an overall history of DST.</li>
+<li><a href="http://toi.iriti.cnr.it/">The
+Time of Internet</a>
+describes time zones and daylight saving time,
+with diagrams.
+The time zone map is out of date, however.</li>
+<li><a href="http://www.phys.uu.nl/~vgent/idl/idl.htm">A History of
+the International Date Line</a> tells the story of the most important
+time zone boundary.</li>
+<li><a href="http://www.statoids.com/tconcept.html">Basic Time
+Zone Concepts</a> discusses terminological issues behind time zones.</li>
+</ul>
+<h2>National histories of legal time</h2>
+<dl>
+<dt>Australia</dt>
+<dd>The Community Relations Division of the New South Wales (NSW)
+Attorney General's Department maintains a <a
+href="http://www.lawlink.nsw.gov.au/crd.nsf/pages/time2">history of
+daylight saving in NSW</a>.</dd>
+<dt>Austria</dt>
+<dd>The Federal Office of Metrology and Surveying publishes a
+table of <a href="http://www.metrologie.at/pdf/sommerzeit.pdf"
+hreflang="de">daylight saving time in Austria (in German)</a>.</dd>
+<dt>Belgium</dt>
+<dd>The Royal Observatory of Belgium maintains a table of <a
+href="http://www.astro.oma.be/GENERAL/INFO/nli001a.html"
+hreflang="nl">time in Belgium (in Dutch)</a>.</dd>
+<dt>Brazil</dt>
+<dd>The Time Service Department of the National Observatory
+records <a href="http://pcdsh01.on.br/DecHV.html"
+hreflang="pt-BR">Brazil's daylight saving time decrees (in
+Portuguese)</a>.</dd>
+<dt>Canada</dt>
+<dd>The Institute for National Measurement Standards publishes current
+and some older information about <a
+href="http://inms-ienm.nrc-cnrc.gc.ca/time_services/daylight_savings_e.html">Time
+Zones and Daylight Saving Time</a>.</dd>
+<dt>Chile</dt>
+<dd>WebExhibits publishes a <a
+href="http://webexhibits.org/daylightsaving/chile.html"
+hreflang="es">history of official time (in Spanish)</a> originally
+written by the Chilean Hydrographic and Oceanographic Service.</dd>
+<dt>Germany</dt>
+<dd>The National Institute for Science and Technology maintains the <a
+href="http://www.ptb.de/en/org/4/44/441/dars_e.htm">Realisation of
+Legal Time in Germany</a>.</dd>
+<dt>Israel</dt>
+<dd>The Interior Ministry periodically issues <a
+href="ftp://ftp.cs.huji.ac.il/pub/tz/announcements/"
+hreflang="he">announcements (in Hebrew)</a>.</dd>
+<dt>Mexico</dt>
+<dd>The Investigation and Analysis Service of the Mexican Library of
+Congress has published a <a
+href="http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/"
+hreflang="es">history of Mexican local time (in Spanish)</a>.</dd>
+<dt>Malaysia</dt>
+<dd>See Singapore below.</dd>
+<dt>Netherlands</dt>
+<dd><a href="http://www.phys.uu.nl/~vgent/wettijd/wettijd.htm"
+hreflang="nl">Legal time in the Netherlands (in Dutch)</a>
+covers the history of local time in the Netherlands from ancient times.</dd>
+<dt>New Zealand</dt>
+<dd>The Department of Internal Affairs maintains a brief history <a
+href="http://www.dia.govt.nz/diawebsite.nsf/wpg_URL/Resource-material-Information-We-Provide-About-Daylight-Saving">about
+daylight saving</a>. The privately-maintained <a
+href="http://www.astrologyhouse.co.nz/timechanges.htm">Time Changes in
+New Zealand</a> has more details.</dd>
+<dt>Singapore</dt>
+<dd><a
+href="http://www.math.nus.edu.sg/aslaksen/teaching/timezone.html">Why
+is Singapore in the "Wrong" Time Zone?</a> details the
+history of legal time in Singapore and Malaysia.</dd>
+<dt>United Kingdom</dt>
+<dd><a
+href="http://www.srcf.ucam.org/~jsm28/british-time/">History of
+legal time in Britain</a> discusses in detail the country
+with perhaps the best-documented history of clock adjustments.
+The National Physical Laboratory also maintains an <a
+href="http://www.npl.co.uk/time/summer_time_archive.html">archive
+of summer time dates</a>.</dd>
+</dl>
+<h2>Precision timekeeping</h2>
+<ul>
+<li><a
+href="http://literature.agilent.com/litwebbin/purl.cgi?org_id=tmo&amp;pub_id=5965-7984E">The
+Science of Timekeeping</a> is a thorough introduction
+to the theory and practice of precision timekeeping.</li>
+<li><a href="http://www.ntp.org/">NTP: The Network Time Protocol</a>
+discusses how to synchronize clocks of
+Internet hosts.</li>
+<li><a href="http://gauss.gge.unb.ca/GMT.UT.and.the.RGO.txt"
+charset="macintosh">A
+Few Facts Concerning GMT, UT, and the RGO</a>
+answers questions like "What is the difference between GMT and UTC?"</li>
+<li><a
+href="http://www.gb.nrao.edu/~rfisher/Ephemerides/times.html">Astronomical
+Times</a> explains more abstruse astronomical time scales like TT, TCG,
+and TDB.</li>
+<li>The <a href="http://www.iau.org/">IAU</a>'s <a
+href="http://www.iau-sofa.rl.ac.uk/">Standards Of Fundamental
+Astronomy</a> (SOFA) initiative publishes Fortran code for converting
+among time scales like TAI, TDB, TT and UTC.</li>
+<li><a href="http://www.jpl.nasa.gov/basics/bsf2-3.htm">Basics of
+Space Flight - Reference Systems - Time Conventions</a>
+briefly explains interplanetary space flight timekeeping.</li>
+<li><a
+href="http://www.giss.nasa.gov/tools/mars24/help/notes.html">Technical
+Notes on Mars Solar Time as Adopted by the Mars24 Sunclock</a> briefly
+describes Mars Coordinated Time (MTC) and the diverse local time
+scales used by each landed mission on Mars.</li>
+<li><a
+href="http://hpiers.obspm.fr/eop-pc/products/bulletins/bulletins.html">Bulletins
+maintained by the IERS EOP (PC)</a> contains official publications of
+the Earth Orientation Parameters Product Center of the
+International Earth Rotation Service, the committee that decides
+when leap seconds occur.</li>
+<li>The <a
+href="http://www.mail-archive.com/leapsecs@rom.usno.navy.mil/">Leap
+Second Discussion List</a> covers McCarthy and Klepczynski's proposal
+to discontinue leap seconds, published in <a
+href="http://www.gpsworld.com/">GPS World</a> <strong>10</strong>, 11
+(1999-11), 50&ndash;57 and discussed further in R. A. Nelson et al.,
+<a href="http://www.cl.cam.ac.uk/~mgk25/time/metrologia-leapsecond.pdf">The
+leap second: its history and possible future</a>,
+<a href="http://www.bipm.fr/metrologia/metrologia.html">Metrologia</a>
+<strong>38</strong> (2001), 509&ndash;529.
+<a href="http://www.ucolick.org/~sla/leapsecs/onlinebib.html">The
+Future of Leap Seconds</a> catalogs information about this
+contentious issue.</li>
+</ul>
+<h2>Time notation</h2>
+<ul>
+<li>
+<a href="http://www.cl.cam.ac.uk/~mgk25/iso-time.html">A Summary of
+the International Standard Date and Time Notation</a> is a good
+summary of ISO
+8601:1988 - Data elements and interchange formats - Information interchange
+- Representation of dates and times (which has been superseded by
+<a href="http://www.iso.org/iso/en/CatalogueDetailPage.CatalogueDetail?CSNUMBER=26780">ISO 8601:2000</a>).</li>
+<li>
+Section 3.3 of <a
+href="ftp://ftp.rfc-editor.org/in-notes/rfc2822.txt">Internet RFC 2822</a>
+specifies the time notation used in email and <a
+href="ftp://ftp.rfc-editor.org/in-notes/rfc2616.txt">HTTP</a> headers.</li>
+<li>
+<a href="ftp://ftp.rfc-editor.org/in-notes/rfc3339.txt">Internet RFC
+3339</a> specifies an ISO 8601 profile for use in new Internet
+protocols.</li>
+<li>
+<a href="http://www.exit109.com/~ghealton/y2k/yrexamples.html">The
+Best of Dates, the Worst of Dates</a> covers many problems encountered
+by software developers when handling dates and time stamps.</li>
+<li>
+Alphabetic time zone abbreviations should not be used as unique
+identifiers for UTC offsets as they are ambiguous in practice. For
+example, "EST" denotes 5 hours behind UTC in English-speaking North
+America, but it denotes 10 or 11 hours ahead of UTC in Australia;
+and French-speaking North Americans prefer "HNE" to "EST". For
+compatibility with <a href="http://www.pasc.org/#POSIX">POSIX</a> the
+<code>tz</code> database contains English abbreviations for all time
+stamps but in many cases these are merely inventions of the database
+maintainers.</li>
+</ul>
+<h2>Related indexes</h2>
+<ul>
+<li><a href="tz-art.htm">Time and the Arts</a></li>
+<li><a href="http://dmoz.org/Reference/Time/">Open Directory -
+Reference: Time</a></li>
+<li><a href="http://directory.google.com/Top/Reference/Time/">Google Directory - Reference &gt; Time</a></li>
+<li><a href="http://dir.yahoo.com/Science/Measurements_and_Units/Time/">Yahoo! Science &gt; Measurements and Units &gt; Time</a></li>
+</ul>
+</body>
+</html>
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