IF your source file is in fact XML, you're much better off using XML::Twig or another XML::Parser derivate.

Otherwise:

local $/;
open my $fh,"<filename";
my $file = <$fh>;
close $fh;
my ($content) = $file =~ /<Directory Filename="([^"]*)"/;
[download]

should get you started. problem areas in this code include: single vs double quotes, xml entities, large files, multiple matches etc. Don't use this as is.