Simple erlang process messaging demonstration

gistfile1.erl

-module(lab).
-compile(export_all).

send_message( GetMsg_PID,  Message ) ->
  GetMsg_PID ! {message, Message},
  io:format(lists:concat(["Sending message ", Message, "\n"]), []).

send_message( GetMsg_PID,  Message, Queue_PID ) ->
  Queue_PID ! {push, Message, "Sending"},
  GetMsg_PID ! {message, Message},
  io:format(lists:concat(["Sending message ", Message, "\n"]), []).

get_message() ->
  receive
    {message, Message} ->
      timer:sleep(1000),
      io:format(lists:concat(["Getting message ", Message, "\n"]), []),
      get_message()
  end.

queue( Q ) ->
  receive
    { push, Element, Label } ->
      io:format(lists:concat([ "In Queue now: ", [Element | Q], Label, "\n"]), []),
      queue( [Element | Q] )
  end.

get_message( Queue_PID ) ->
  receive
    {message, Message} ->
      Queue_PID ! {push, Message, "Got"},
      io:format(lists:concat(["Getting message ", Message, "\n"]), []),
      get_message(Queue_PID)
  end.

start(Message) ->
%    GetMsg_PID = spawn( lab, get_message, [] ),
%    spawn(lab, send_message, [GetMsg_PID, Message]),
%    spawn(lab, send_message, [GetMsg_PID, "1"]),
%    spawn(lab, send_message, [GetMsg_PID, "2"]),
%    spawn(lab, send_message, [GetMsg_PID, "3"]),
%    spawn(lab, send_message, [GetMsg_PID, "4"]),

    QueueG_PID = spawn( lab, queue, [[]] ),
    QueueS_PID = spawn( lab, queue, [[]] ),
    GetMsgQ_PID = spawn( lab, get_message, [QueueG_PID] ),
    spawn(lab, send_message, [GetMsgQ_PID, " Privet1 ", QueueS_PID]),
    spawn(lab, send_message, [GetMsgQ_PID, " Privet2 ", QueueS_PID]),
    spawn(lab, send_message, [GetMsgQ_PID, " Privet3 ", QueueS_PID]).