Command-line script for displaying world clocks, allows zonefiles or zone names inputs.

README.mkd

cliclock.sh

Command-line script for displaying world clocks, allows zonefiles or zone names inputs.

Forked from Gist, which was from an Stackoverflow answer.

Heavily modified by Yu-Jie Lin.

cliclock.sh

#!/bin/sh
# Command-line world clock
# Taken from  http://stackoverflow.com/questions/370075/command-line-world-clock
# Modified by Yu-Jie Lin

# usage:
#   cliclock.sh [[zonefile|zonename] ...]
#
# zonename can be full or partial, e.g. America/New_York or 'new york'
#
# default ~/.worldclock.zones and zonefile looks like:
# US/Pacific
# Europe/Berlin
# Chile/Continental
# new york
# Los Angeles

: ${WORLDCLOCK_FORMAT:='%Y-%m-%d %H:%M:%S %Z'}

if (( $# == 0 )); then
  : ${WORLDCLOCK_ZONES:=$HOME/.worldclock.zones}
  if [[ ! -f $WORLDCLOCK_ZONES ]]; then
    echo 'no zones to display' >&2
    exit 1
  fi
  OLDIFS="$IFS"
  IFS=$'\n'
  WORLDCLOCK_ZONES=($(cat "$WORLDCLOCK_ZONES"))
  IFS="$OLDIFS"
else
  while (( $# > 0)); do
    if [[ -f "$1" ]]; then
      OLDIFS="$IFS"
      IFS=$'\n'
      WORLDCLOCK_ZONES=("${WORLDCLOCK_ZONES[@]}" $(cat "$1"))
      IFS="$OLDIFS"
    else
      WORLDCLOCK_ZONES=("${WORLDCLOCK_ZONES[@]}" "$1")
    fi
    shift
  done
fi

ZONEINFO='/usr/share/zoneinfo/'
VALID_ZONES=($(find "$ZONEINFO" -path '*/right' -prune -o -type f | sed "s|^$ZONEINFO||"))
shopt -s nocasematch
# Checking zones and set the max length
check_zone() {
  local zone z
  ret=
  z="*${1// /?}*"
  for zone in "${VALID_ZONES[@]}"; do
    if [[ $zone == $z ]]; then
      ret="$zone"
      return
    fi
    #  match first zone with $zone as substring
    if [[ ! -z $ret ]] && [[ $zone == $z ]]; then
      ret="$zone"
    fi
  done
}

zones=()
MAX_ZONE_LEN=0
for zone in "${WORLDCLOCK_ZONES[@]}"; do
  check_zone "$zone"
  if [[ -z $ret ]]; then
    echo invalid zone $zone >&2
    continue
  fi
  zone="$ret"
  zones=("${zones[@]}" "$zone")
  (( ${#zone} > MAX_ZONE_LEN )) && MAX_ZONE_LEN=${#zone}
done
unset VALID_ZONES

if (( ${#zones[@]} == 0 )); then
  echo 'no zones to display' >&2
  exit 1
fi

# Some zones are invalid, keep error message for 3 seconds
(( ${#zones[@]} != ${#WORLDCLOCK_ZONES[@]} )) && sleep 3
unset WORLDCLOCK_ZONES

while :; do
  clear
  printf -v now '%(%s)T' -1
  for zone in "${zones[@]}"; do
    TZ=$zone printf "%-${MAX_ZONE_LEN}s  %($WORLDCLOCK_FORMAT)T\n" "$zone" "$now"
  done
  # Allow to elegantly quit this script
  if read -n 1 -t 1 -s; then
    case "$REPLY" in
      q|Q)
        break
        ;;
    esac
  fi
done