tzdiff
Displays Timezone differences with localtime in CLI (shell script)
Tzdiff or Timediff ?
This command was originally "timediff". Now, it's "tzdiff" because of naming conflict.
Usage
tzdiff [-0] [-n count] [-f format] [-t time] timezone [timezone ...] [count] [0]
Tzdiff with no arguments will display list of timezones. Tzdiff with timezone will display the time differences of remote time with local time.
Options
- -h: show usage
- -0: round down to hour
- -n count: max hours (default: 10)
- -f format: output format (using '+output_fmt' of date(1))
- -t time: set the start time instead of current time. 'YYYY-mm-ddTHH:MM' or 'YYYYmmddTHHMM' is ok.
- -H: became the scripting mode. Fields are explicitly separated by single tab instead of an arbitrary space.
- -HH: became the scripting mode without timzone name.
- -N: display without local timezone.
Install
FreeBSD
If you are pkg user, you can easy to install tzdiff like this.
$ sudo pkg install tzdiff
Of course, it is already in ports. You can easy to play with ports.
macOS
If you are MacPorts user, you can easy to install tzdiff.
$ sudo port install tzdiff
If you are Homebrew user, you can install by personal tap.
$ brew tap belgianbeer/minmin
$ brew install tzdiff
Debian / Ubuntu
Currently, tzdiff become a debian pkg in progress. ( tzdiff in Debin pkg ) In near future, it can easy to install by apt command.
$ sudo apt update
$ sudo apt install tzdiff
Examples
In these examples, author's timezone is JST.
$ tzdiff
Africa/ Australia/ Etc/ MST WET
America/ CET Europe/ MST7MDT posixrules
Antarctica/ CST6CDT Factory PST8PDT zone.tab
Arctic/ EET HST Pacific/
Asia/ EST Indian/ SystemV/
Atlantic/ EST5EDT MET UTC
$ tzdiff America/Los_Angeles
America/Los_Angeles
2017-05-12 05:55 PDT 2017-05-12 21:55 JST
2017-05-12 06:55 PDT 2017-05-12 22:55 JST
2017-05-12 07:55 PDT 2017-05-12 23:55 JST
2017-05-12 08:55 PDT 2017-05-13 00:55 JST
2017-05-12 09:55 PDT 2017-05-13 01:55 JST
2017-05-12 10:55 PDT 2017-05-13 02:55 JST
2017-05-12 11:55 PDT 2017-05-13 03:55 JST
2017-05-12 12:55 PDT 2017-05-13 04:55 JST
2017-05-12 13:55 PDT 2017-05-13 05:55 JST
2017-05-12 14:55 PDT 2017-05-13 06:55 JST
Tzdiff supports TIMEZONE's completion. For example,
$ tzdiff Lon # enter RETURN instead of TAB
Arctic/Longyearbyen Europe/London
$ tzdiff Lond
Europe/London
2017-05-31 07:10 BST 2017-05-31 15:10 JST
2017-05-31 08:10 BST 2017-05-31 16:10 JST
2017-05-31 09:10 BST 2017-05-31 17:10 JST
2017-05-31 10:10 BST 2017-05-31 18:10 JST
2017-05-31 11:10 BST 2017-05-31 19:10 JST
2017-05-31 12:10 BST 2017-05-31 20:10 JST
2017-05-31 13:10 BST 2017-05-31 21:10 JST
2017-05-31 14:10 BST 2017-05-31 22:10 JST
2017-05-31 15:10 BST 2017-05-31 23:10 JST
2017-05-31 16:10 BST 2017-06-01 00:10 JST
$ tzdiff New_ 0 5
America/New_York
2017-05-12 08:00 EDT 2017-05-12 21:00 JST
2017-05-12 09:00 EDT 2017-05-12 22:00 JST
2017-05-12 10:00 EDT 2017-05-12 23:00 JST
2017-05-12 11:00 EDT 2017-05-13 00:00 JST
2017-05-12 12:00 EDT 2017-05-13 01:00 JST
It is easy to check changes from daylight saving time to standard time
$ tzdiff -t 2017-11-05T11:00 Los New_ Brus
America/Los_Angeles America/New_York Europe/Brussels
2017-11-04 19:00 PDT 2017-11-04 22:00 EDT 2017-11-05 03:00 CET 2017-11-05 11:00 JST
2017-11-04 20:00 PDT 2017-11-04 23:00 EDT 2017-11-05 04:00 CET 2017-11-05 12:00 JST
2017-11-04 21:00 PDT 2017-11-05 00:00 EDT 2017-11-05 05:00 CET 2017-11-05 13:00 JST
2017-11-04 22:00 PDT 2017-11-05 01:00 EDT 2017-11-05 06:00 CET 2017-11-05 14:00 JST
2017-11-04 23:00 PDT 2017-11-05 01:00 EST 2017-11-05 07:00 CET 2017-11-05 15:00 JST
2017-11-05 00:00 PDT 2017-11-05 02:00 EST 2017-11-05 08:00 CET 2017-11-05 16:00 JST
2017-11-05 01:00 PDT 2017-11-05 03:00 EST 2017-11-05 09:00 CET 2017-11-05 17:00 JST
2017-11-05 01:00 PST 2017-11-05 04:00 EST 2017-11-05 10:00 CET 2017-11-05 18:00 JST
2017-11-05 02:00 PST 2017-11-05 05:00 EST 2017-11-05 11:00 CET 2017-11-05 19:00 JST
2017-11-05 03:00 PST 2017-11-05 06:00 EST 2017-11-05 12:00 CET 2017-11-05 20:00 JST
Tzdiff works with the following operating systems.
- macOS / FreeBSD / NetBSD / OpenBSD (It may work on DragonFly BSD.)
- Debian / Ubuntu / CentOS and many Linux distros
- Windows subsystem for Linux