1308265SgjbREADME for the tz distribution
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3345670Sphilip"Where do I set the hands of the clock?" -- Les Tremayne as The King
4345670Sphilip"Oh that--you can set them any place you want." -- Frank Baxter as The Scientist
5308265Sgjb					(from the Bell System film "About Time")
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7339630SphilipThe Time Zone Database (called tz, tzdb or zoneinfo) contains code and
8308265Sgjbdata that represent the history of local time for many representative
9308265Sgjblocations around the globe.  It is updated periodically to reflect
10308265Sgjbchanges made by political bodies to time zone boundaries, UTC offsets,
11308265Sgjband daylight-saving rules.
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13309792SbaptSee <https://www.iana.org/time-zones/repository/tz-link.html> or the
14328475Sphilipfile tz-link.html for how to acquire the code and data.  Once acquired,
15309792Sbaptread the comments in the file 'Makefile' and make any changes needed
16308265Sgjbto make things right for your system, especially if you are using some
17308265Sgjbplatform other than GNU/Linux.  Then run the following commands,
18308265Sgjbsubstituting your desired installation directory for "$HOME/tzdir":
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20308265Sgjb	make TOPDIR=$HOME/tzdir install
21328475Sphilip	$HOME/tzdir/usr/bin/zdump -v America/Los_Angeles
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23366625SphilipSee the file tz-how-to.html for examples of how to read the data files.
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25339630SphilipThis database of historical local time information has several goals:
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27339630Sphilip * Provide a compendium of data about the history of civil time that
28339630Sphilip   is useful even if not 100% accurate.
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30339630Sphilip * Give an idea of the variety of local time rules that have existed
31339630Sphilip   in the past and thus may be expected in the future.
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33339630Sphilip * Test the generality of the local time rule description system.
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35308265SgjbThe information in the time zone data files is by no means authoritative;
36308265Sgjbfixes and enhancements are welcome.  Please see the file CONTRIBUTING
37308265Sgjbfor details.
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39308265SgjbThanks to these Time Zone Caballeros who've made major contributions to the
40308265Sgjbtime conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz;
41308265SgjbGuy Harris; Mark Horton; John Mackin; and Bradley White.  Thanks also to
42308265SgjbMichael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales
43308265Sgjbfor testing work, and to Gwillim Law for checking local mean time data.
44308265SgjbThanks in particular to Arthur David Olson, the project's founder and first
45308265Sgjbmaintainer, to whom the time zone community owes the greatest debt of all.
46308265SgjbNone of them are responsible for remaining errors.
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48308265Sgjb-----
49308265Sgjb
50308265SgjbThis file is in the public domain, so clarified as of 2009-05-17 by
51308265SgjbArthur David Olson.  The other files in this distribution are either
52308265Sgjbpublic domain or BSD licensed; see the file LICENSE for details.
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