.\" Copyright (c) 1991 The Regents of the University of California.
.\" This code is derived from software contributed to Berkeley by
.\" Arthur David Olson of the National Cancer Institute.
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" @(#)zic.8 5.2 (Berkeley) 4/20/91
zic \- time zone compiler
reads text from the file(s) named on the command line
and creates the time conversion information files specified in this input.
the standard input is read.
These options are available:
Create time conversion information files in the named directory rather than
in the standard directory named below.
Use the given time zone as local time.
will act as if the input contained a link line of the form
Link \fItimezone\fP localtime
Use the given time zone's rules when handling POSIX-format
time zone environment variables.
will act as if the input contained a link line of the form
Link \fItimezone\fP posixrules
.BI "\-L " leapsecondfilename
Read leap second information from the file with the given name.
If this option is not used,
no leap second information appears in output files.
Complain if a year that appears in a data file is outside the range
of years representable by
Limit time values stored in output files to values that are the same
whether they're taken to be signed or unsigned.
You can use this option to generate SVVS-compatible files.
Input lines are made up of fields.
Fields are separated from one another by any number of white space characters.
Leading and trailing white space on input lines is ignored.
An unquoted sharp character (#) in the input introduces a comment which extends
to the end of the line the sharp character appears on.
White space characters and sharp characters may be enclosed in double quotes
(") if they're to be used as part of a field.
Any line that is blank (after comment stripping) is ignored.
Non-blank lines are expected to be of one of three types:
rule lines, zone lines, and link lines.
.ta \w'Rule\0\0'u +\w'NAME\0\0'u +\w'FROM\0\0'u +\w'1973\0\0'u +\w'TYPE\0\0'u +\w'Apr\0\0'u +\w'lastSun\0\0'u +\w'2:00\0\0'u +\w'SAVE\0\0'u
Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule USA 1969 1973 \- Apr lastSun 2:00 1:00 D
The fields that make up a rule line are:
Gives the (arbitrary) name of the set of rules this rule is part of.
Gives the first year in which the rule applies.
(or an abbreviation) means the minimum year with a representable time value.
(or an abbreviation) means the maximum year with a representable time value.
Gives the final year in which the rule applies.
may be used to repeat the value of the
Gives the type of year in which the rule applies.
then the rule applies in all years between
the rule applies in U.S. Presidential election years;
the rule applies in years other than U.S. Presidential election years.
\fByearistype\fP \fIyear\fP \fItype\fP
to check the type of a year:
an exit status of zero is taken to mean that the year is of the given type;
an exit status of one is taken to mean that the year is not of the given type.
Names the month in which the rule takes effect.
Month names may be abbreviated.
Gives the day on which the rule takes effect.
Recognized forms include:
lastSun the last Sunday in the month
lastMon the last Monday in the month
Sun>=8 first Sunday on or after the eighth
Sun<=25 last Sunday on or before the 25th
Names of days of the week may be abbreviated or spelled out in full.
Note that there must be no spaces within the
Gives the time of day at which the rule takes effect.
Recognized forms include:
2:00 time in hours and minutes
15:00 24-hour format time (for times after noon)
1:28:14 time in hours, minutes, and seconds
Any of these forms may be followed by the letter
if the given time is local
if the given time is local
wall clock time is assumed.
Gives the amount of time to be added to local standard time when the rule is in
This field has the same format as the
(although, of course, the
of time zone abbreviations to be used when this rule is in effect.
the variable part is null.
.ta \w'Zone\0\0'u +\w'Australia/South\-west\0\0'u +\w'GMTOFF\0\0'u +\w'RULES/SAVE\0\0'u +\w'FORMAT\0\0'u
Zone NAME GMTOFF RULES/SAVE FORMAT [UNTIL]
Zone Australia/South\-west 9:30 Aus CST 1987 Mar 15 2:00
The fields that make up a zone line are:
The name of the time zone.
This is the name used in creating the time conversion information file for the
The amount of time to add to GMT to get standard time in this zone.
This field has the same format as the
begin the field with a minus sign if time must be subtracted from GMT.
The name of the rule(s) that apply in the time zone or,
alternately, an amount of time to add to local standard time.
then standard time always applies in the time zone.
The format for time zone abbreviations in this time zone.
is used to show where the
of the time zone abbreviation goes.
The time at which the GMT offset or the rule(s) change for a location.
It is specified as a year, a month, a day, and a time of day.
the time zone information is generated from the given GMT offset
and rule change until the time specified.
line; this has the same form as a zone line except that the
and the name are omitted, as the continuation line will
place information starting at the time specified as the
field in the previous line in the file used by the previous line.
Continuation lines may contain an
field, just as zone lines do, indicating that the next line is a further
.if t .ta \w'Link\0\0'u +\w'LINK-FROM\0\0'u
.if n .ta \w'Link\0\0'u +\w'US/Eastern\0\0'u
field should appear as the
field is used as an alternate name for that zone.
Except for continuation lines,
lines may appear in any order in the input.
Lines in the file that describes leap seconds have the following form:
.ta \w'Leap\0\0'u +\w'YEAR\0\0'u +\w'MONTH\0\0'u +\w'DAY\0\0'u +\w'HH:MM:SS\0\0'u +\w'CORR\0\0'u
Leap YEAR MONTH DAY HH:MM:SS CORR R/S
Leap 1974 Dec 31 23:59:60 + S
fields tell when the leap second happened.
should be (an abbreviation of)
if the leap second time given by the other fields should be interpreted as GMT
if the leap second time given by the other fields should be interpreted as
For areas with more than two types of local time,
you may need to use local standard time in the
field of the earliest transition time's rule to ensure that
the earliest transition time recorded in the compiled file is correct.
/etc/zoneinfo standard directory used for created files
newctime(3), tzfile(5), zdump(8)