TestClient/testclient.erl

-module(testclient).
-export([start_client/0]).

-define(TCP_OPTIONS, [binary, {packet, 0}, {active, true}]).
-define(PORT, 9001).
-define(HOST, "127.0.0.1").
-define(DATASIZE, 4096).

loop(Socket) ->
    receive
	    {tcp, Socket, Bin} ->
	        gen_tcp:send(Socket, Bin),
	        loop(Socket);
	    {tcp_closed, Socket}->
	        io:format("Socket ~p closed~n", [Socket]);
	    {tcp_error, Socket, Reason} ->
	        io:format("Error on socket ~p reason: ~p~n", [Socket, Reason])
    end.

start_client() ->
    {ok, Sock} = gen_tcp:connect(?HOST, ?PORT, ?TCP_OPTIONS),
    Pid = spawn(fun() -> 
        io:format("Connection established ~n", []),
        loop(Sock) 
    end),
    gen_tcp:controlling_process(Sock, Pid),
    Message = crypto:strong_rand_bytes(?DATASIZE),
    gen_tcp:send(Sock, Message).