1README for the tz distribution 2 3"Where do I set the hands of the clock?" -- Les Tremayne as The King 4"Oh that--you can set them any place you want." -- Frank Baxter as The Scientist 5 (from the Bell System film "About Time") 6 7The Time Zone Database (called tz, tzdb 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 13See <https://www.iana.org/time-zones/repository/tz-link.html> or the 14file tz-link.html for how to acquire the code and data. 15 16Once acquired, read the leading comments in the file "Makefile" 17and make any changes needed to make things right for your system, 18especially when using a platform other than current GNU/Linux. 19 20Then run the following commands, substituting your desired 21installation directory for "$HOME/tzdir": 22 23 make TOPDIR="$HOME/tzdir" install 24 "$HOME/tzdir/usr/bin/zdump" -v America/Los_Angeles 25 26See the file tz-how-to.html for examples of how to read the data files. 27 28This database of historical local time information has several goals: 29 30 * Provide a compendium of data about the history of civil time that 31 is useful even if not 100% accurate. 32 33 * Give an idea of the variety of local time rules that have existed 34 in the past and thus may be expected in the future. 35 36 * Test the generality of the local time rule description system. 37 38The information in the time zone data files is by no means authoritative; 39fixes and enhancements are welcome. Please see the file CONTRIBUTING 40for details. 41 42Thanks to these Time Zone Caballeros who've made major contributions to the 43time conversion package: Keith Bostic; Bob Devine; Paul Eggert; Robert Elz; 44Guy Harris; Mark Horton; John Mackin; and Bradley White. Thanks also to 45Michael Bloom, Art Neilson, Stephen Prince, John Sovereign, and Frank Wales 46for testing work, and to Gwillim Law for checking local mean time data. 47Thanks in particular to Arthur David Olson, the project's founder and first 48maintainer, to whom the time zone community owes the greatest debt of all. 49None of them are responsible for remaining errors. 50 51----- 52 53This file is in the public domain, so clarified as of 2009-05-17 by 54Arthur David Olson. The other files in this distribution are either 55public domain or BSD licensed; see the file LICENSE for details. 56