anchor.diff:    (let* ((disk (partition host))
            (fat32 (fat32-structure host))
            (fat (fat host)))
  -    (multiple-value-bind (directory cluster-sector start) (find-file host path)
  +    (multiple-value-bind (directory cluster-n start) (find-file host path)
         (assert start (start) "File/directory not found. ~s" path)
  -      (remove-file directory start disk cluster-sector fat32 fat))))
  +      (remove-file directory start disk cluster-n fat32 fat))))
   
   (defmethod expunge-directory-using-host ((host fat32-host) path &key)
     (declare (ignore host path))
  
positive.code:         (when (not successp)
            (error "Disk write error: ~S" error-reason))))))
  
  (defun read-cluster (fat32 disk cluster-sector)
    "Read cluster data from disk"
    (let* ((spc (fat32-sectors-per-cluster fat32))
           (cluster-data (make-array (* spc (mezzano.supervisor:disk-sector-size disk))
                                     :area :wired :element-type '(unsigned-byte 8))))
      (multiple-value-bind (successp error-reason) (mezzano.supervisor:disk-read disk cluster-sector spc cluster-data)
        (when (not successp)
          (error "Disk read error: ~S" error-reason)))
      cluster-data))
  
  (defun write-cluster (disk cluster-sector fat32 cluster-data)
    "Write cluster data to disk"
    (multiple-value-bind (successp error-reason)
        (mezzano.supervisor:disk-write disk cluster-sector (fat32-sectors-per-cluster fat32)
                                       (make-array (length cluster-data)
                                                   :area :wired :element-type '(unsigned-byte 8)
                                                   :initial-contents cluster-data))
      (when (not successp)
        (error "Disk write error: ~S" error-reason))))
  
  ;;; bit offsets
  (defconstant +attribute-read-only+ 0)
  (defconstant +attribute-hidden+ 1)
  
negative.code:           (read-buffer-size 0)
            (created-file nil)
            (abort-action nil))
        (multiple-value-bind (file-data cluster-n start) (find-file host pathname)
          (declare (ignore cluster-n))
          (if start
              (setf buffer (read-file (fat32-structure host)
                                      (partition host)
                                      (read-first-cluster file-data start)
                                      (fat host))
                    read-buffer-position (read-first-cluster file-data start)
                    read-buffer-size (read-size file-data start))
              (ecase if-does-not-exist
                (:error (error 'simple-file-error
                               :pathname pathname
  