xref: /dragonfly/share/zoneinfo/README (revision 6ab64ab6)
1README for the tz distribution
2
3"What time is it?" -- Richard Deacon as The King
4"Any time you want it to be." -- Frank Baxter as The Scientist
5					(from the Bell System film "About Time")
6
7The Time Zone Database (often called tz or zoneinfo) contains code and
8data that represent the history of local time for many representative
9locations around the globe.  It is updated periodically to reflect
10changes made by political bodies to time zone boundaries, UTC offsets,
11and daylight-saving rules.
12
13Here is a recipe for acquiring, building, installing, and testing the
14tz distribution on a GNU/Linux or similar host.
15
16	mkdir tz
17	cd tz
18	wget --retr-symlinks 'ftp://ftp.iana.org/tz/tz*-latest.tar.gz'
19	gzip -dc tzcode-latest.tar.gz | tar -xf -
20	gzip -dc tzdata-latest.tar.gz | tar -xf -
21
22Be sure to read the comments in "Makefile" and make any changes needed
23to make things right for your system, especially if you are using some
24platform other than GNU/Linux.  Then run the following commands,
25substituting your desired installation directory for "$HOME/tzdir":
26
27	make TOPDIR=$HOME/tzdir install
28	$HOME/tzdir/etc/zdump -v America/Los_Angeles
29
30Historical local time information has been included here to:
31
32*	provide a compendium of data about the history of civil time
33	that is useful even if not 100% accurate;
34
35*	give an idea of the variety of local time rules that have
36	existed in the past and thus an idea of the variety that may be
37	expected in the future;
38
39*	provide a test of the generality of the local time rule description
40	system.
41
42The information in the time zone data files is by no means authoritative;
43fixes and enhancements are welcome.  Please see the file CONTRIBUTING
44for details.
45
46Thanks to these Time Zone Caballeros who've made major contributions to the
47time conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz;
48Guy Harris; Mark Horton; John Mackin; and Bradley White.  Thanks also to
49Michael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales
50for testing work, and to Gwillim Law for checking local mean time data.
51Thanks in particular to Arthur David Olson, the project's founder and first
52maintainer, to whom the time zone community owes the greatest debt of all.
53None of them are responsible for remaining errors.
54
55Look in <ftp://ftp.iana.org/tz/releases/> for updated versions of these files.
56
57Please send comments or information to tz@iana.org.
58
59-----
60
61This file is in the public domain, so clarified as of 2009-05-17 by
62Arthur David Olson.  The other files in this distribution are either
63public domain or BSD licensed; see the file LICENSE for details.
64