00000001.did
00000001.mrg
00000002.did
00000002.mrg
00000003.did

##</code><code>##

sub unmergedFiles
{
	my $dir = shift;
	my %merged;
	my @files;
	
	# create the hash containing the merged files
	foreach (glob ($dir."/*.mrg"))
	{
		if ( /(\S+)\.mrg/i )
		{
			$merged{lc ($1 . ".did")} = "1";
		}
	}
	
	foreach (glob ($dir."/*.did"))
	{
		unless (exists $merged{lc($_)})
		{
			push @files, $_;
		}
	}
	# return style as per node 311537!
	return wantarray ? @files : \@files;
}