Source

File: wp-includes/IXR/class-IXR-date.php

function parseTimestamp($timestamp)
    {
        $this->year = gmdate('Y', $timestamp);
        $this->month = gmdate('m', $timestamp);
        $this->day = gmdate('d', $timestamp);
        $this->hour = gmdate('H', $timestamp);
        $this->minute = gmdate('i', $timestamp);
        $this->second = gmdate('s', $timestamp);
        $this->timezone = '';
    }