#!/bin/sh
# show date and time in filtered time zones.
# tzdate :: timezone-name

search=$1
zoneinfo=/usr/share/zoneinfo/posix/
format='%a %F %T'

find $zoneinfo -type f \
  | grep -i "$search" \
  | while read z
    do
      d=$(TZ=$z date +"$format")
      printf "%-34s %23s\n" ${z#$zoneinfo} "$d"
    done