my $twig = new XML::Twig::XPath( TwigHandlers => {
	#ITPSL header parsing data
	"/itpslsig/itpslheader/ontology/weightmatrix" => \&getwm, 
	"/itpslsig/itpslheader/ontology/detectby" => \&getdetectmethods,
	"/itpslsig/itpslheader/ontology/os" => \&getos,
	"/itpslsig/itpslheader/ontology/osver" => \&getosver,
	#ITPSL body parsing data
	"/itpslsig/itpslbody/mainblock/mainop" => \&getmainop,
	"/itpslsig/itpslbody/mainblock" => \&getnoofsubblocks,
	"/itpslsig/itpslbody/mainblock/subblock" => \&parsesubs,
	
});
# parse, handling nodes on the way
$twig->parsefile( shift @ARGV );