anchor.diff:  (defpackage :ach
     (:use :cl :binio :usocket)
     (:export :ach-connect :ach-close :ach-read :ach-write
  -           :ach-next :ach-last :ach-put
  +           :ach-next :ach-last :ach-put :ach-map
              :make-listener :make-ach-syncpipe))
   
   (in-package :ach)
  
positive.code:     (force-output s)
      (make-channel :mode mode
                    :synchronous synchronous
                    :transport sock)))
  
  (defun ach-close (channel)
    (socket-close (channel-transport channel)))
  
negative.code: (defstruct channel
    mode
    synchronous
    transport
    name
    host)
  
  (defun channel-input (channel)
    (socket-stream (channel-transport channel)))
  