1.\" 2.\" $FreeBSD: src/usr.sbin/zic/zdump.8,v 1.7.2.2 2003/03/11 22:31:35 trhodes Exp $ 3.\" 4.Dd October 19, 2008 5.Dt ZDUMP 8 6.Os 7.Sh NAME 8.Nm zdump 9.Nd timezone dumper 10.Sh SYNOPSIS 11.Nm 12.Op Fl v 13.Op Fl c Bo Ar loyear Ns , Bc Ns Ar hiyear 14.Op Ar zonename ... 15.Sh DESCRIPTION 16The 17.Nm 18utility prints the current time in each 19.Ar zonename 20named on the command line. 21.Pp 22The following options are available: 23.Bl -tag -width indent 24.It Fl v 25For each 26.Ar zonename 27on the command line, 28print the time at the lowest possible time value, 29the time one day after the lowest possible time value, 30the times both one second before and exactly at 31each detected time discontinuity, 32the time at one day less than the highest possible time value, 33and the time at the highest possible time value, 34Each line ends with 35.Em isdst=1 36if the given time is Daylight Saving Time or 37.Em isdst=0 38otherwise. 39.It Fl c Bo Ar loyear Ns , Bc Ns Ar hiyear 40Cut off verbose output near the start of the given year(s). 41By default, 42the program cuts off verbose output near the starts of the years -500 and 2500. 43.El 44.Sh LIMITATIONS 45The 46.Fl v 47option may not be used on systems with floating-point 48.Vt time_t 49values that are neither float nor double. 50.Pp 51Time discontinuities are found by sampling the results returned by 52.Xr localtime 3 53at twelve-hour intervals. 54This works in all real-world cases; 55one can construct artificial time zones for which this fails. 56.Sh "SEE ALSO" 57.Xr ctime 3 , 58.Xr tzfile 5 , 59.Xr zic 8 60