1 README for the tz distribution
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")
7 The Time Zone Database (often called tz or zoneinfo) contains code and
8 data that represent the history of local time for many representative
9 locations around the globe. It is updated periodically to reflect
10 changes made by political bodies to time zone boundaries, UTC offsets,
11 and daylight-saving rules.
13 Here is a recipe for acquiring, building, installing, and testing the
14 tz distribution on a GNU/Linux or similar host.
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 -
22 Be sure to read the comments in "Makefile" and make any changes needed
23 to make things right for your system, especially if you are using some
24 platform other than GNU/Linux. Then run the following commands,
25 substituting your desired installation directory for "$HOME/tzdir":
27 make TOPDIR=$HOME/tzdir install
28 $HOME/tzdir/etc/zdump -v America/Los_Angeles
30 Historical local time information has been included here to:
32 * provide a compendium of data about the history of civil time
33 that is useful even if not 100% accurate;
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;
39 * provide a test of the generality of the local time rule description
42 The information in the time zone data files is by no means authoritative;
43 fixes and enhancements are welcome. Please see the file CONTRIBUTING
46 Thanks to these Time Zone Caballeros who've made major contributions to the
47 time conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz;
48 Guy Harris; Mark Horton; John Mackin; and Bradley White. Thanks also to
49 Michael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales
50 for testing work, and to Gwillim Law for checking local mean time data.
51 Thanks in particular to Arthur David Olson, the project's founder and first
52 maintainer, to whom the time zone community owes the greatest debt of all.
53 None of them are responsible for remaining errors.
55 Look in <ftp://ftp.iana.org/tz/releases/> for updated versions of these files.
57 Please send comments or information to tz@iana.org.
61 This file is in the public domain, so clarified as of 2009-05-17 by
62 Arthur David Olson. The other files in this distribution are either
63 public domain or BSD licensed; see the file LICENSE for details.