function unix2DosTime($unixtime = 0)
{
$timearray = $unixtime == 0 ? getdate() : getdate($unixtime);
if ($timearray['year'] < 1980) {
$timearray['year'] = 1980;
$timearray['mon'] = 1;
$timearray['mday'] = 1;
$timearray['hours'] = 0;
$timearray['minutes'] = 0;
$timearray['seconds'] = 0;
}
return $timearray['year'] - 1980 << 25 | $timearray['mon'] << 21 | $timearray['mday'] << 16 | $timearray['hours'] << 11 | $timearray['minutes'] << 5 | $timearray['seconds'] >> 1;
}