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1ba2b2efdSGlen BarberREADME for the tz distribution
2ba2b2efdSGlen Barber
3ba2b2efdSGlen Barber"What time is it?" -- Richard Deacon as The King
4ba2b2efdSGlen Barber"Any time you want it to be." -- Frank Baxter as The Scientist
5ba2b2efdSGlen Barber					(from the Bell System film "About Time")
6ba2b2efdSGlen Barber
7ba2b2efdSGlen BarberThe Time Zone Database (often called tz or zoneinfo) contains code and
8ba2b2efdSGlen Barberdata that represent the history of local time for many representative
9ba2b2efdSGlen Barberlocations around the globe.  It is updated periodically to reflect
10ba2b2efdSGlen Barberchanges made by political bodies to time zone boundaries, UTC offsets,
11ba2b2efdSGlen Barberand daylight-saving rules.
12ba2b2efdSGlen Barber
13*e350c46aSBaptiste DaroussinSee <https://www.iana.org/time-zones/repository/tz-link.html> or the
14*e350c46aSBaptiste Daroussinfile tz-link.htm for how to acquire the code and data.  Once acquired,
15*e350c46aSBaptiste Daroussinread the comments in the file 'Makefile' and make any changes needed
16ba2b2efdSGlen Barberto make things right for your system, especially if you are using some
17ba2b2efdSGlen Barberplatform other than GNU/Linux.  Then run the following commands,
18ba2b2efdSGlen Barbersubstituting your desired installation directory for "$HOME/tzdir":
19ba2b2efdSGlen Barber
20ba2b2efdSGlen Barber	make TOPDIR=$HOME/tzdir install
21ba2b2efdSGlen Barber	$HOME/tzdir/etc/zdump -v America/Los_Angeles
22ba2b2efdSGlen Barber
23ba2b2efdSGlen BarberHistorical local time information has been included here to:
24ba2b2efdSGlen Barber
25ba2b2efdSGlen Barber*	provide a compendium of data about the history of civil time
26ba2b2efdSGlen Barber	that is useful even if not 100% accurate;
27ba2b2efdSGlen Barber
28ba2b2efdSGlen Barber*	give an idea of the variety of local time rules that have
29ba2b2efdSGlen Barber	existed in the past and thus an idea of the variety that may be
30ba2b2efdSGlen Barber	expected in the future;
31ba2b2efdSGlen Barber
32ba2b2efdSGlen Barber*	provide a test of the generality of the local time rule description
33ba2b2efdSGlen Barber	system.
34ba2b2efdSGlen Barber
35ba2b2efdSGlen BarberThe information in the time zone data files is by no means authoritative;
36ba2b2efdSGlen Barberfixes and enhancements are welcome.  Please see the file CONTRIBUTING
37ba2b2efdSGlen Barberfor details.
38ba2b2efdSGlen Barber
39ba2b2efdSGlen BarberThanks to these Time Zone Caballeros who've made major contributions to the
40ba2b2efdSGlen Barbertime conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz;
41ba2b2efdSGlen BarberGuy Harris; Mark Horton; John Mackin; and Bradley White.  Thanks also to
42ba2b2efdSGlen BarberMichael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales
43ba2b2efdSGlen Barberfor testing work, and to Gwillim Law for checking local mean time data.
44ba2b2efdSGlen BarberThanks in particular to Arthur David Olson, the project's founder and first
45ba2b2efdSGlen Barbermaintainer, to whom the time zone community owes the greatest debt of all.
46ba2b2efdSGlen BarberNone of them are responsible for remaining errors.
47ba2b2efdSGlen Barber
48ba2b2efdSGlen Barber-----
49ba2b2efdSGlen Barber
50ba2b2efdSGlen BarberThis file is in the public domain, so clarified as of 2009-05-17 by
51ba2b2efdSGlen BarberArthur David Olson.  The other files in this distribution are either
52ba2b2efdSGlen Barberpublic domain or BSD licensed; see the file LICENSE for details.
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