Zdump prints the current time in each zonename named on the command line.
These options are available:
-v For each zonename on the command line, print the current time, 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 time at which the rules for computing local
time change, the time at the highest possible time value, and the time at one day less than the highest possible time value. Each
line ends with isdst=1 if the given time is Daylight Saving Time or isdst=0 otherwise.
Cut off the verbose output near the start of the given year.
/usr/share/zoneinfo standard zone information directory