if($sort_field eq 'createtime') {
	for $node (sort {
		($date, $time) = split / /, $nodes{$a}{createtime};
		($year, $month, $day) = split /-/, $date;
		($hour, $min, $sec) = split /:/, $time;
		$create_timeA = timelocal($sec,$min,$hour,$day,$month,$year);
		($date, $time) = split / /, $nodes{$b}{createtime};
		($year, $month, $day) = split /-/, $date;
		($hour, $min, $sec) = split /:/, $time;
		$create_timeB = timelocal($sec,$min,$hour,$day,$month,$year);
		if($sort_order eq 'ASC') {
			return $create_timeA <=> $create_timeB;
		} else {
			return $create_timeB <=> $create_timeA;
		}
	} keys %nodes) {
			print "$node: $nodes{$node}{$sort_field}\n";
	}
} else {
   whatever;
}