opendir (DIR, $backupdir) or die $!;
      my @files = readdir DIR;
      print "\@files is: \n";
      foreach (@files) {
         print $_, "\n";
      }

      if (grep {$back} @files) {
         print "Backup copy of $filename exists!\n";
      }
      else {
         copy($filename, $backful); 
         print "Backup copy of the file has been created\n";
      }