1. 1. read in "list" and find the two most recent dumps
  2. 2. run a compare on them putting the new names to a file (system call)
  3. 3. delete the oldest file (system call)

open LIST, "list"; $new=""; $old=""; while (<LIST>){

      chomp();
     $old=$new;
     $new=$_;

} close LIST; system "\\cygwin\\bin\\comm -1 -3 $old $new > newlist.txt"; if ($old ne ""){

     system "del $old";

}