- date_create: documentation ( source)
- print_r: documentation ( source)
- strtotime: documentation ( source)
<?php
$timestamp = strtotime('0000-02-20 00:00:00 UTC');
$timestamp2 = strtotime('0001-02-20 00:00:00 UTC');
print $timestamp . "\n";
$date_time = date_create('@' . $timestamp);
print_r($date_time);
print $timestamp2 . "\n";
$date_time2 = date_create('@' . $timestamp2);
print_r($date_time2);