LISP IO Samples 20150820

LISP IO Samples 20120825 - Shammerismに一部追加。

File 読み込み

(with-open-file (input-stream "$READ_FILE_NAME" :direction :input)
  (loop
    (let ((line (read-line input-stream nil 'eof)))
      (if (eql line 'eof) (return))
	(format t "~A~%" line)))))

(with-open-file (stream path :direction :input)
  (do ((line ;Value Name
        (read-line stream nil 'eof) ;Initial Value
        (read-line stream nil 'eof))) ;Step
      ((eql line 'eof)) ; Finish Judgement
    (format t "~A~%" line)))

File 書き出し

ファイルが存在していない前提の場合

(with-open-file (output-stream "$OUTPUT_FILE_NAME" :direction :output)
  (format output-stream "Hello!"))

ファイルが存在しているか確認する(since 20150820)

(when (probe-file *file*)
  (do () ()
    (format t "~A is already exists, would you like overwrite it?(yes/no):" *file*)
    (let ((answer (read-line)))
      (cond ((string-equal answer "no")
	     (format t "Nothing will be done.~%")
	     (quit))
	    ((string-equal answer "yes")
	     (format t "~A will be overwritten.~%" *file*)
	     (return))
	    (t
	     (format t "~A is an invalid answer, the answer should be yes or no with case-insensitive.~%" *file*))))))
(with-open-file (stream *file :direction :output)
  (format stream "~A~%" "Hello!~%"))

File 書き足し

(with-open-file (stream path :direction :output :if-exists :append :if-does-not-exist :error)
  (format stream "~A~%" "Hello, World!")
  (format stream "~A~%" "END OF FILE"))

TCP Passive Socket

(defun open-echo-server ()
  (with-open-socket (server :type :stream
			    :connect :passive
			    :local-host "localhost"
			    :local-port 8080
			    :reuse-address t)
		    (let ((client (accept-connection server)))
		      (format t "> Server received a message: ~%")
		      (do ((line (read-line client nil nil)
				 (read-line client nil nil)))
			  ((or (string-equal line (string '#\Return))
			        (eql line nil)))
			(dolist (i (coerce line 'list))
			  (format t "~:c" i))
			(format t "~%"))
		      (format t "> Received Complete...~%")
		      (close client))))

UDP Passive Socket

(let ((server (make-socket :type :datagram
			   :local-host "127.0.0.1"
			   :local-port 7001
			   :format :binary)))
  (do ()
      ()
    (multiple-value-bind (buffer length client-ip client-port)
	(receive-from server 512)
      (format t "Received data is ~A~%" buffer)
      (format t "Received data length is ~A~%" length)
      (format t "SRC-IP addr is ~A~%" client-ip)
      (format t "SRC-Port is ~A~%" client-port))))

TCP Active Socket

(defun send-message (destination-host destination-port message)
  (with-open-socket (client :address-family :internet
			    :type :stream
			    :connect :active
			    :remote-host destination-host
			    :remote-port destination-port)
		    (format client message)
		    (format client "~%")
		    (force-output client)))

UDP Active Socket

(let ((client (make-socket :type :datagram)))
  (multiple-value-bind (char-vector count)
      (encode-string-to-octets "Test" :external-format :UTF-8)
    (format t "char-vector is ~A~%" char-vector)
    (format t "char-vector type is ~A~%" (type-of char-vector))
    (format t "count is ~A~%" count)
    (send-to client char-vector count :remote-host "127.0.0.1" :remote-port 7001)))

(quit)