DragonFly On-Line Manual Pages

ZDUMP(8)               DragonFly System Manager's Manual              ZDUMP(8)

NAME
     zdump - timezone dumper

SYNOPSIS
     zdump [-vV] [-c [loyear,]hiyear] [-t [lotime,]hitime] [zonename ...]

DESCRIPTION
     The zdump utility prints the current time in each zonename named on the
     command line.

     The following options are available:

     -v      For each zonename on the command line, print the time at the
             lowest possible time value, the time one day after the lowest
             possible time value, the times both one second before and exactly
             at each detected time discontinuity, the time at one day less
             than the highest possible time value, and the time at the highest
             possible time value, Each line ends with isdst=1 if the given
             time is Daylight Saving Time or isdst=0 otherwise.

     -V      Like -v, except omit the times relative to the extreme time
             values.  This generates output that is easier to compare to that
             of implementations with different time representations.

     -c [loyear,]hiyear
             Cut off verbose output near the start of the given year(s).  By
             default, the program cuts off verbose output near the starts of
             the years -500 and 2500.

     -t [lotime,]hitime
             Cut off verbose output at the start of the given time(s), given
             in decimal seconds since 1970-01-01 00:00:00 UTC.

LIMITATIONS
     The -v option may not be used on systems with floating-point time_t
     values that are neither float nor double.

     Time discontinuities are found by sampling the results returned by
     localtime(3) at twelve-hour intervals.  This works in all real-world
     cases; one can construct artificial time zones for which this fails.

     In the output, "UT" denotes the value returned by gmtime(3), which uses
     UTC for modern time stamps and some other UT flavor for time stamps that
     predate the introduction of UTC.  No attempt is currently made to have
     the output use "UTC" for newer and "UT" for older time stamps, partly
     because the exact date of the introduction of UTC is problematic.

SEE ALSO
     ctime(3), tzfile(5), zic(8)

DragonFly 6.3-DEVELOPMENT      December 8, 2013      DragonFly 6.3-DEVELOPMENT