The program prints the current time in each named on
the command line.
Output version information and exit. Output short usage message and exit. Output
a description of time intervals. For each on the command line, output an
interval-format description of the timezone. See below. Output a verbose
description of time intervals. For each on the command line, print the times
at the two extreme time values, the times (if present) at and just beyond the
boundaries of years that localtime(3) and gmtime(3) can
represent, and the times both one second before and exactly at each detected
time discontinuity. Each line is followed by where is positive, zero, or
negative depending on whether the given time is daylight saving time, standard
time, or an unknown time type, respectively. Each line is also followed by if
the given local time is known to be seconds east of Greenwich. Cut off
interval output at the given year(s). Cutoff times are computed using the
proleptic Gregorian calendar with year 0 and with Universal Time (UT) ignoring
leap seconds. Cutoffs are at the start of each year, where the lower-bound
timestamp is inclusive and the upper is exclusive; for example, selects
transitions on or after 1970-01-01 00:00:00 UTC and before 2070-01-01 00:00:00
UTC. The default cutoff is Cut off interval output at the given time(s), given
in decimal seconds since 1970-01-01 00:00:00 Coordinated Universal Time (UTC).
The determines whether the count includes leap seconds. As with the cutoff's
lower bound is inclusive and its upper bound is exclusive. Like except omit
output concerning extreme time and year values. This generates output that is
easier to compare to that of implementations with different time
representations. The interval format is a compact text representation that is
intended to be both human- and machine-readable. It consists of an empty line,
then a line where is a double-quoted string giving the timezone, a second line
describing the time interval before the first transition if any, and zero or
more following lines one line for each transition time and following interval.
Fields are separated by single tabs. Dates are in format and times are in
24-hour format where Times are in local time immediately after the transition.
A time interval description consists of a UT offset in signed format, a time
zone abbreviation, and an isdst flag. An abbreviation that equals the UT
offset is omitted; other abbreviations are double-quoted strings unless they
consist of one or more alphabetic characters. An isdst flag is omitted for
standard time, and otherwise is a decimal integer that is unsigned and
positive (typically 1) for daylight saving time and negative for unknown. In
times and in UT offsets with absolute value less than 100 hours, the seconds
are omitted if they are zero, and the minutes are also omitted if they are
also zero. Positive UT offsets are east of Greenwich. The UT offset -00
denotes a UT placeholder in areas where the actual offset is unspecified; by
convention, this occurs when the UT offset is zero and the time zone
abbreviation begins with or is In double-quoted strings, escape sequences
represent unusual characters. The escape sequences are \s for space, and
\", \\, \f, \n, \r, \t, and \v with their usual meaning in the C
programming language. E.g., the double-quoted string represents the character
sequence Here is an example of the output, with the leading empty line
omitted. (This example is shown with tab stops set far enough apart so that
the tabbed columns line up.) TZ="Pacific/Honolulu" Here, local time
begins 10 hours, 31 minutes and 26 seconds west of UT, and is a standard time
abbreviated LMT. Immediately after the first transition, the date is
1896-01-13 and the time is 12:01:26, and the following time interval is 10.5
hours west of UT, a standard time abbreviated HST. Immediately after the
second transition, the date is 1933-04-30 and the time is 03:00:00 and the
following time interval is 9.5 hours west of UT, is abbreviated HDT, and is
daylight saving time. Immediately after the last transition the date is
1947-06-08 and the time is 02:30:00, and the following time interval is 10
hours west of UT, a standard time abbreviated HST. Here are excerpts from
another example: TZ="Europe/Astrakhan" This time zone is east of UT,
so its UT offsets are positive. Also, many of its time zone abbreviations are
omitted since they duplicate the text of the UT offset. Time discontinuities
are found by sampling the results returned by at twelve-hour intervals. This
works in all real-world cases; one can construct artificial time zones for
which this fails. In the and output, denotes the value returned by which uses
UTC for modern timestamps and some other UT flavor for timestamps that predate
the introduction of UTC. No attempt is currently made to have the output use
for newer and for older timestamps, partly because the exact date of the
introduction of UTC is problematic.