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Time zone database and code
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Latest commit 0f03a53 @eggert Release tzcode2016a and tzdata2016a.
* NEWS, Makefile (VERSION): Increase to 2016a.
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Makefile Release tzcode2016a and tzdata2016a.
NEWS Release tzcode2016a and tzdata2016a.
README Clarify licensing status
Theory Cite Ogle's 2015 book on history of civil time
africa Revert previous change, about Morocco
antarctica Propagate Chile changes to Antarctica/Palmer
asctime.c Fix EOVERFLOW-related problems noted by Chistos Zoulas.
asia Cite Ogle's 2015 book on history of civil time
australasia Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
backward Remove America/Santa_Isabel
backzone Cayman shelved DST plans
checklinks.awk Clarify licensing status
checktab.awk Clarify licensing status
date.1 Port 'date' better to POSIX 1003.1-2001 and later
date.c Clarify licensing status
difftime.c Avoid unnecessary casts in difftime
etcetera Simplify use of URLs in text files.
europe Asia/Chita switches to +0900 in March 2016
factory Simplify use of URLs in text files. Spell Åland etc. with accents in
leap-seconds.list No leap second on 2015-12-31.
leapseconds.awk * leapseconds.awk, NEWS: Also output expiration date comment.
localtime.c Fix signed 32-bit time_t localtime bug on Fiji
newctime.3 Add documentation for the core NetBSD-inspired functions.
newstrftime.3 Clarify licensing status
newtzset.3 Fiji observes DST from 2014-11-02 02:00 to 2015-01-18 03:00.
northamerica Cayman shelved DST plans
pacificnew Switch back to ASCII for symbols.
private.h Declare timezone, daylight, altzone in private.h
southamerica A few more instances of "No."
strftime.c Clarify licensing status
systemv Simplify use of URLs in text files.
time2posix.3 Document thread-safe functions in man pages.
tz-art.htm * tz-art.htm: Add The Good Wife 2016-01-17.
tz-link.htm Fix tz-link DC.Title and case
tzfile.5 Remove synopsis from tzfile man page
tzfile.h Use bool for boolean.
tzselect.8 Rename to
tzselect.ksh Clarify licensing status Simplify use of URLs in text files. Distinguish hyphen from minus from dashes.
zdump.8 * zdump.8: Be more specific about when a year starts.
zdump.c Pacify Visual Studio 2013 'const' yet again
zic.8 Support %z in Zone formats
zic.c Fix sign of %z output, and add DST offset Metlakatla switched from PST to AKST/AKDT Cayman shelved DST plans Rename fields of Link lines for clarity.


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 (often called tz 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.

Here is a recipe for acquiring, building, installing, and testing the
tz distribution on a GNU/Linux or similar host.

	mkdir tz
	cd tz
	wget --retr-symlinks '*-latest.tar.gz'
	gzip -dc tzcode-latest.tar.gz | tar -xf -
	gzip -dc tzdata-latest.tar.gz | tar -xf -

Be sure to read the comments in "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/etc/zdump -v America/Los_Angeles

Historical local time information has been included here to:

*	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 an idea of the variety that may be
	expected in the future;

*	provide a test of the generality of the local time rule description

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.

Look in <> for updated versions of these files.

Please send comments or information to


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.
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