<?php
ini_set('date.timezone', 'Europe/Lisbon');
ini_set('intl.default_locale', 'en_US');
ini_set('intl.error_level', E_WARNING);
//On October 27th at 0200, the clock goes back 1 hour and from GMT+01 to GMT+00
$cal = new IntlGregorianCalendar(2013, 9 /* October */, 27, 1, 30);
var_dump($cal->getRepeatedWalltimeOption()); // 0 WALLTIME_LAST
$formatter = IntlDateFormatter::create(
NULL,
IntlDateFormatter::FULL,
IntlDateFormatter::FULL,
'UTC'
);
var_dump($formatter->format($cal->getTime() / 1000.));
$cal->setRepeatedWalltimeOption(IntlCalendar::WALLTIME_FIRST);
var_dump($cal->getRepeatedWalltimeOption()); // 1 WALLTIME_FIRST
$cal->set(IntlCalendar::FIELD_HOUR_OF_DAY, 1);
var_dump($formatter->format($cal->getTime() / 1000.));
The above example will output:
int(0)
string(42) "Sunday, October 27, 2013 at 1:30:00 AM GMT"
int(1)
string(43) "Sunday, October 27, 2013 at 12:30:00 AM GMT"