anchor.diff:         do
            (setf (elt name idx) char)
            (incf idx))
  -
       ;; Copy chars for 3 part, if there is any
       (when (/= (aref directory (+ 8 offset)) (char-code #\Space))
         (setf (elt name idx) #\.)
  
positive.code:     (let ((next (aref fat cluster-n)))
        (setf (aref fat cluster-n) 0
              cluster-n next)))
  
    ;; mark directory entry (or entries) as free
    (free-file-entry directory start)
  
    ;; Write to disk
    (write-fat disk fat32 fat)
    (write-file fat32 disk cluster-n fat directory))
  
negative.code:            (setf (aref directory offset) #xE5)
             (when (logbitp 6 first-byte)
               (return)))))
    ;; mark short name directory entry as free
    (setf (aref directory start) #xE5))
  
  