file_02_0.xml.xml:
file_03_0.xml.xml:
file_04_0.xml.xml:
file_05_0.xml.xml:

##</code><code>##

file_02_0.xml.bak.xml:
file_03_0.xml.bak.xml:
file_04_0.xml.bak.xml:
file_05_0.xml.bak.xml:

##</code><code>##

#Separating xml and backup files 

my @xml_files = glob( '*xml' );
#say for @xml_files;

my @bak_files = glob( '*bak' );
#say for @bak_files;

#Show differences between file_01.xml and file_01.xml.bak, etc...

open my $FH, '>', "file_difference_report" or die $!;
my @base_file_names = ( @xml_files, @bak_files );
print Dumper \@base_file_names;
print "\n\n\n";
for my $file_name ( @base_file_names ) {
	if ( ! -e "$file_name.xml" ){
		print "$file_name.xml: Not present ... not interesting file?\n";
		next;
	}
	if ( ! -e "$file_name.bak" ){
		print "$file_name: no backup, so probably not changed\n";
		next;
	}
	# If we get here, we have a .bak and a .xml file, so make another
	# program to compare them for us:
	my $output = 'diff $file_name.xml $file_name.bak';
	print $FH "\n\n===== $file_name changes =====\n";
    print $FH $output;
    print $FH "\n\n";
}