anchor.diff:    (socket  fd)
     (backlog :int))
   
  -(define-socket-call "recv" ssize
  -  (socket fd)
  -  (buffer :pointer)
  -  (length size)
  -  (flags  :int))
  -
   (define-socket-call "recvfrom" ssize
     (socket  fd)
     (buffer  :pointer)
  
positive.code:   (flags    :int)
    (destaddr :pointer)
    (destlen  socklen))
  
  (define-socket-call "setsockopt" :int
    "Configure a socket."
  
negative.code:   (address :pointer)
    (addrlen :pointer))
  
  (define-socket-call "sendto" ssize
    (socket   fd)
    (buffer   :pointer)
  