...	
my @record_types = qw(100 200 300 400 500);
...
# Daten die reinkommen
$record_type_found = substr($file_content,$position+12,3);
	
	foreach (@record_types) {
		if ($record_type_found == $_) 
		{ 
			$record_type_status = "ok"; 
			last; 
		}
		$record_type_status = "not ok"; #
	}
	print $record_type_found, ": ", $record_type_status, "\n";