Usage

whattime --now --display new_york,utc
# TZ=America/New_York date; TZ=Etc/UTC date

whattime --when '2pm' --here --display new_york
# TZ=America/New_York date -d 'TZ="/usr/share/zoneinfo/<your timezone>" 2pm'

whattime --when '2pm' --in 'new york' --display chicago
# TZ=America/Chicago date -d 'TZ="America/New_York" 2pm'

TODO

• good flag names and abilities
• helpful region checks (scan in /usr/share/zoneinfo/)
• fixed-width pretty table formatting (printf)
• good date and time zone parsing (use date under the hood?)
  • check info date
  • maybe accept time offsets and map them to TZs?
• work on Mac OS and Debian
• maybe csv output style?

Questions we want to answer:

• when it is 2pm in NY, what time is it here and LA
• what time is it in Taipei right now?
• when it is 2pm here, what time is it in Chicago?

Two different kinds of locations:

• where we fix the time --where
• location for which to display the time --display

Helpful links:

• https://superuser.com/questions/164339/timezone-conversion-by-command-line/164354#164354