function client_ip()
{
	if(isset($_SERVER['HTTP_X_REAL_IP'])) {
		return $_SERVER['HTTP_X_REAL_IP'];
	} else {
		if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
			return $_SERVER['HTTP_CLIENT_IP'];
		} elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) {
			return $_SERVER['HTTP_X_FORWARDED_FOR'];
		} else {
			return $_SERVER['REMOTE_ADDR'];
		}
	}
}

echo client_ip();