use XML::DOM;
use strict;
use File::Find;
use XML::SAX;
use XML::SAX::Writer;
use XML::Filter::XInclude;
use File::Copy;
use IO::File;

my $output = new IO::File "> output.xml";
my $parser = XML::SAX::ParserFactory->parser(
     Handler => XML::Filter::XInclude->new(
        Handler => XML::SAX::Writer->new(Output=>$output)
     )
);
$parser->parse_uri("./project.xml");