Create a network service that sits on TCP port 12321, which accepts connections on that port, and which echoes complete lines (using a carriage-return/line-feed sequence as line separator) back to clients. No error handling is required. For the purposes of testing, it is only necessary to support connections from localhost (127.0.0.1 or perhaps ::1). Logging of connection information to standard output is recommended.

The implementation must be able to handle simultaneous connections from multiple clients. A multi-threaded or multi-process solution may be used. Each connection must be able to echo more than a single line.

The implementation must not stop responding to other clients if one client sends a partial line or stops reading responses.

(use '[clojure.contrib.server-socket :only (create-server)])
(use '[clojure.contrib.duck-streams :only (read-lines write-lines)])
 
(defn echo [input output]
  (write-lines (java.io.PrintWriter. output true) (read-lines input)))
 
(create-server 12321 echo)