Shell script to convert a timestamp to NZ time

utc2nz

#!/usr/bin/env php
<?php
$originTimeZone = 'UTC';
$targetTimeZone = 'Pacific/Auckland';

////////////////////////

$timestamp = implode(' ', array_slice($_SERVER['argv'], 1));

$origin = new DateTimeZone($originTimeZone);
$target = new DateTimeZone($targetTimeZone);

$date = (new DateTimeImmutable($timestamp, $origin))->setTimeZone($origin);

////////////////////////

printf(
    "%s: %s\n%s: %s\n",
    $originTimeZone,
    $date->format('r'),
    $targetTimeZone,
    $date->setTimezone($target)->format('r')
);