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README for the tz distribution 
 
"What time is it?" -- Richard Deacon as The King 
"Any time you want it to be." -- Frank Baxter as The Scientist 
                                        (from the Bell System film "About Time") 
 
The Time Zone Database (called tz, tzdb or zoneinfo) 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 time zone boundaries, UTC offsets, 
and daylight-saving rules. 
 
See <https://www.iana.org/time-zones/repository/tz-link.html> or the 
file tz-link.html for how to acquire the code and data.  Once acquired, 
read the comments in the file '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/usr/bin/zdump -v America/Los_Angeles 
 
This database of historical local time information has several goals: 
 
 * Provide a compendium of data about the history of civil time that 
   is useful even if not 100% accurate. 
 
 * Give an idea of the variety of local time rules that have existed 
   in the past and thus may be expected in the future. 
 
 * Test the generality of the local time rule description system. 
 
The information in the time zone data files is by no means authoritative; 
fixes and enhancements are welcome.  Please see the file CONTRIBUTING 
for details. 
 
Thanks to these Time Zone Caballeros who've made major contributions to the 
time conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz; 
Guy Harris; Mark Horton; John Mackin; and Bradley White.  Thanks also to 
Michael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales 
for testing work, and to Gwillim Law for checking local mean time data. 
Thanks in particular to Arthur David Olson, the project's founder and first 
maintainer, to whom the time zone community owes the greatest debt of all. 
None of them are responsible for remaining errors. 
 
----- 
 
This file is in the public domain, so clarified as of 2009-05-17 by 
Arthur David Olson.  The other files in this distribution are either 
public domain or BSD licensed; see the file LICENSE for details.