my @directory = ("C:\Testing");
	my $srcfile;
	my @sourcefiles;
	$datfile = uc(test_file_name.dat);
	find(\&sourcefind, @directory);
	sub sourcefind {
	    open(FL, $File::Find::name);
	    $sourcefile = $_ if -f and /$datfile/ ; 
	    close(FL);
	}
the program has to find successful match if the filename is following
Case 1 : test_file_name.dat (all lower case)
Case 2 : TEST_FILE_NAME.DAT (all upper case)
Case 3 : Test_File_Name.dat (Mixed)