anchor.diff:           (byte-3    (read-my-byte stream))
            (byte-4    (read-my-byte stream))
            (unsigned
  -          (logior (ash byte-4 24) (ash byte-3 16) (ash byte-2  8) byte-1)))
  -    (declare (type fixnum unsigned))
  +          (logior (ash byte-4 24) (ash byte-3 16) (ash byte-2 8) byte-1)))
       (if signed (unsigned-to-signed unsigned 3) unsigned)))
   
   (defun read-6-bytes-integer (stream  &key signed)
  
positive.code:   (let* ((byte-1    (read-my-byte stream))
           (byte-2    (read-my-byte stream))
           (unsigned  (logior (ash byte-2 8) byte-1)))
      (declare (type fixnum unsigned))
      (if signed (unsigned-to-signed unsigned 2) unsigned)))
  
  (defun read-3-bytes-integer (stream  &key signed)
  
negative.code: (declaim (inline unsigned-to-signed read-fixed-length-integer))
  
  (defun unsigned-to-signed (byte n)
    (declare (type fixnum n) (type unsigned-byte byte))
    (logior byte (- (mask-field (byte 1 (1- (* n 8))) byte))))
  
  (defun read-2-bytes-integer (stream &key signed)
  