e? port-number))
    (let ((p (open-tcp-client
              (list server-address: host
                    port-number: port-number))))
      (cons p p)))
  (define flush-output-port force-output)
  (define close-tcp-connection close-port)

  ; DL: by analogue with Gambit 3
  (define shutdown-sender force-output)

; Previous version for Gambit 3
;  ; The Gambit implementation relies on internal Gambit procedures,
;  ; whose names start with ##
;  ; Such identifiers cannot be _read_ on many other systems
; 