Manual Pages  — ZDUMP

zdump – timezone dumper

SYNOPSIS DESCRIPTION LIMITATIONS SEE ALSO

zdump [--version] [-v] [-c [loyear,]hiyear] [zonename ...]

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

The following options are available:

--version
	Output version information and exit.
-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.
-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.

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 at twelve-hour intervals. This works in all real-world cases; one can construct artificial time zones for which this fails.