christos cf47161082 Merge tzcode2018c [ changelog with changes to tzdata sections removed ]
Release 2018c - 2018-01-22 23:00:44 -0800

  Changes to build procedure

    The build procedure now works around mawk 1.3.3's lack of support
    for character class expressions.  (Problem reported by Ohyama.)


Release 2018b - 2018-01-17 23:24:48 -0800

  Changes to build procedure

    The distribution now contains the file 'pacificnew' again.
    This file was inadvertantly omitted in the 2018a distribution.
    (Problem reported by Matias Fonzo.)


Release 2018a - 2018-01-12 22:29:21 -0800

  Changes to build procedure

    The default installation locations have been changed to mostly
    match Debian circa 2017, instead of being designed as an add-on to
    4.3BSD circa 1986.  This affects the Makefile macros TOPDIR,
    TZDIR, MANDIR, and LIBDIR.  New Makefile macros TZDEFAULT, USRDIR,
    USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
    locations more precisely.  (This responds to suggestions from
    Brian Inglis and from Steve Summit.)

    The default installation procedure no longer creates the
    backward-compatibility link US/Pacific-New, which causes
    confusion during user setup (e.g., see Debian bug 815200).
    Use 'make BACKWARD="backward pacificnew"' to create the link
    anyway, for now.  Eventually we plan to remove the link entirely.

    tzdata.zi now contains a version-number comment.
    (Suggested by Tom Lane.)

    The Makefile now quotes values like BACKWARD more carefully when
    passing them to the shell.  (Problem reported by Zefram.)

    Builders no longer need to specify -DHAVE_SNPRINTF on platforms
    that have snprintf and use pre-C99 compilers.  (Problem reported
    by Jon Skeet.)

  Changes to code

    zic has a new option -t FILE that specifies the location of the
    file that determines local time when TZ is unset.  The default for
    this location can be configured via the new TZDEFAULT makefile
    macro, which defaults to /etc/localtime.

    Diagnostics and commentary now distinguish UT from UTC more
    carefully; see theory.html for more information about UT vs UTC.

    zic has been ported to GCC 8's -Wstringop-truncation option.
    (Problem reported by Martin Sebor.)

  Changes to documentation and commentary

    The zic man page now documents the longstanding behavior that
    times and years can be out of the usual range, with negative times
    counting backwards from midnight and with year 0 preceding year 1.
    (Problem reported by Michael Deckers.)

    The theory.html file now mentions the POSIX limit of six chars
    per abbreviation, and lists alphabetic abbreviations used.

    The files tz-art.htm and tz-link.htm have been renamed to
    tz-art.html and tz-link.html, respectively, for consistency with
    other file names and to simplify web server configuration.
2018-01-25 22:48:42 +00:00
..

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.

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

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
	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.