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.Dd Dec 21, 2018
.Dt TZDIFF 1
.Os
.Sh NAME
.Nm tzdiff
.Nd displays timezone differences with localtime.
.Sh SYNOPSIS
.Nm
.Op Fl 0
.Op Fl n Ar count
.Op Fl f Ar format
.Op Fl t Ar time
timzone
.Op timezone ...
.Op count
.Op 0
.Sh DESCRIPTION
The
.Nm
utility displays the localtime of the designated timezone and yours.
.Pp
The
.Nm
utility needs at least one of timezone name, such as
.Dq Asia/Tokyo .
If the argument is
.Dq Asia
then
.Nm
displays the timezones of Asia. You can easy to choose it from the result.
.Pp
The
.Nm
supports the complition with name of timezone for useful.
For example,
.Dq Tok
means
.Dq Asia/Tokyo .
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl 0
Round down to hour. 0(zero) may be specified as the last argument.
.It Fl n Ar count
Number of hours. Default is 10. It may be specified as the last argument.
.It Fl h
Show usage.
.It Fl f Ar fmt
Output format of time. It uses output format of
.Xr date 1
.It Fl t Ar arg
Specify the start time.
It supports one of
.Dq YYYY-mm-ddThh:mm
or
.Dq YYYYmmddThhmm .
.It Fl H
Scripting mode with timezone name. In scripting mode, field separator is TAB instead of space.
.It Fl HH
Scripting mode without timezone name.
.It Fl N
Display without local timezone.
.El
.Sh EXAMPLES
These exsamples are in JST.
.Pp
The command:
.Pp
.Dl tzdiff
.Pp
will display the result of
.Dq "ls -F /usr/share/zoneinfo" :
.Bd -literal -offset indent
Africa/       Australia/    Etc/          MST           WET
America/      CET           Europe/       MST7MDT       posixrules
--- snip --- snip --- snip ---
Asia/         EST           Indian/       SystemV/
Atlantic/     EST5EDT       MET           UTC
.Ed
.Pp
The command:
.Pp
.Dl "tzdiff Eu"
.Pp
will display the result of
.Dq "ls -F /usr/share/zoneinfo/Europe" :
.Bd -literal -offset indent
Europe/Amsterdam        Europe/Kiev             Europe/Sarajevo
Europe/Andorra          Europe/Kirov            Europe/Saratov
--- snip --- snip --- snip ---
Europe/Jersey           Europe/Samara
Europe/Kaliningrad      Europe/San_Marino
.Ed
.Pp
The command:
.Pp
.Dl "tzdiff Europe/Amsterdam"
.Pp
will display the time of CET and localtime.:
.Pp
.Bd -literal -offset indent
Europe/Amsterdam
2018-12-19 14:52 CET    2018-12-19 22:52 JST
2018-12-19 15:52 CET    2018-12-19 23:52 JST
--- snip --- snip --- snip ---
2018-12-19 22:52 CET    2018-12-20 06:52 JST
2018-12-19 23:52 CET    2018-12-20 07:52 JST
.Ed
.Pp
The command:
.Pp
.Dl "tzdiff Lond New_ 0 3"
.Pp
will display:
.Bd -literal -offset indent
Europe/London           America/New_York
2018-12-20 01:00 GMT    2018-12-19 20:00 EST    2018-12-20 10:00 JST
2018-12-20 02:00 GMT    2018-12-19 21:00 EST    2018-12-20 11:00 JST
2018-12-20 03:00 GMT    2018-12-19 22:00 EST    2018-12-20 12:00 JST
.Ed
.Sh SEE ALSO
.Xr date 1 ,
.Xr strftime 3 ,
.Xr strptime 3
.Pp
.Nm
on Github: https://github.com/belgianbeer/tzdiff
.Sh AUTHOR
Written by
.An Masato Minda