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diff --git a/system_cmds/zic.tproj/README b/system_cmds/zic.tproj/README new file mode 100644 index 0000000..ff974e9 --- /dev/null +++ b/system_cmds/zic.tproj/README @@ -0,0 +1,88 @@ +@(#)README 8.3 +This file is in the public domain, so clarified as of +2009-05-17 by Arthur David Olson. + +$FreeBSD: head/contrib/tzcode/zic/README 192890 2009-05-27 12:18:39Z edwin $ + +"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 1989 update of the time zone package featured + +* POSIXization (including interpretation of POSIX-style TZ environment + variables, provided by Guy Harris), +* ANSIfication (including versions of "mktime" and "difftime"), +* SVIDulation (an "altzone" variable) +* MACHination (the "gtime" function) +* corrections to some time zone data (including corrections to the rules + for Great Britain and New Zealand) +* reference data from the United States Naval Observatory for folks who + want to do additional time zones +* and the 1989 data for Saudi Arabia. + +(Since this code will be treated as "part of the implementation" in some places +and as "part of the application" in others, there's no good way to name +functions, such as timegm, that are not part of the proposed ANSI C standard; +such functions have kept their old, underscore-free names in this update.) + +And the "dysize" function has disappeared; it was present to allow compilation +of the "date" command on old BSD systems, and a version of "date" is now +provided in the package. The "date" command is not created when you "make all" +since it may lack options provided by the version distributed with your +operating system, or may not interact with the system in the same way the +native version does. + +Since POSIX frowns on correct leap second handling, the default behavior of +the "zic" command (in the absence of a "-L" option) has been changed to omit +leap second information from its output files. + +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 'ftp://elsie.nci.nih.gov/pub/tz*.tar.gz' + gzip -dc tzcode*.tar.gz | tar -xf - + gzip -dc tzdata*.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 + +To use the new functions, use a "-ltz" option when compiling or linking. + +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 the data are 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; +the files currently do not even attempt to cover all time stamps before +1970, and there are undoubtedly errors even for time stamps since 1970. +If you know that the rules are different from those in a file, by all means +feel free to change file (and please send the changed version to +tz@elsie.nci.nih.gov for use in the future). Europeans take note! + +Thanks to these Timezone 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. +None of them are responsible for remaining errors. + +Look in the ~ftp/pub directory of elsie.nci.nih.gov +for updated versions of these files. + +Please send comments or information to tz@elsie.nci.nih.gov. |