Erlang Node Configuration - concurrency

Question

I'm working through the examples on the Erlang website on Concurrency. I'm currently working on section 3.5 which implements a simple chat messenger.
Here is the code:
-module(messenger).
-export([start_server/0, server/1, goOnline/1, goOffline/0, message/2, client/2]).
server_node() ->
messenger#bill.
server(User_List) ->
receive
{From, logon, Name} ->
New_User = server_goOnline(From, Name, User_List),
server(New_User);
{From, logoff} ->
New_User = server_goOffline(From, User_List),
server(New_User);
{From, message_to, To, Message} ->
server_transfer(From, To, Message, User_List),
io:format("list is now: ~p~n", [User_List]),
server(User_List)
end.
start_server() ->
register(messenger, spawn(messager, server, [[]])).
server_goOnline(From, Name, User_List) ->
case lists:keymember(Name, 2, User_List) of
true ->
From ! {messenger, stop, user_exists_at_other_node},
User_List;
false ->
From ! {messenger, logged_on},
[{From, Name} | User_List]
end.
server_goOffline(From, User_List) ->
lists:keydelete(From, 1, User_List).
server_transfer(From, To, Message, User_List) ->
case lists:keysearch(From, 1, User_List) of
false ->
From ! {messenger, stop, you_are_not_logged_on};
{value, {From, Name}} ->
server_transfer(From, Name, To, Message, User_List)
end.
server_transfer(From, Name, To, Message, User_List) ->
case lists:keysearch(To, 2, User_List) of
false ->
From ! {messenger, receiver_not_found};
{value, {ToPid, To}} ->
ToPid ! {message_from, Name, Message},
From ! {messenger, sent}
end.
goOnline(Name) ->
case whereis(mess_client) of
undefined ->
register(mess_client,
spawn(messenger, client, [server_node(), Name]));
_ -> already_logged_on
end.
goOffline() ->
mess_client ! logoff.
message(ToName, Message) ->
case whereis(mess_client) of
undefined ->
not_logged_on;
_ -> mess_client ! {message_to, ToName, Message},
ok
end.
client(Server_Node, Name) ->
{messenger, Server_Node} ! {self(), goOnline, Name},
await_result(),
client(Server_Node).
client(Server_Node) ->
receive
logoff ->
{messenger, Server_Node} ! {self(), logoff},
exit(normal);
{message_to, ToName, Message} ->
{messenger, Server_Node} ! {self(), message_to, ToName, Message},
await_result();
{message_from, FromName, Message} ->
io:format("Message From ~p: ~p~n", [FromName, Message])
end,
client(Server_Node).
await_result() ->
receive
{messenger, stop, Why} ->
io:format("~p~n", [Why]),
exit(normal);
{messneger, What} ->
io:format("~p~n", [What])
end.
The tutorial says to configure server_node() -> to the node where my messenger server runs. How do I configure that function? I don't exactly know what that means, My question would be how do I configure the server_node to register my server location for messenger.

Answer 1

If you start erlang using the command erl -sname somename, you should have a prompt of the form:
(somename#pcname)1>
simply replace the code
server_node() ->
messenger#bill.
by
server_node() ->
somename#pcname.
and recompile the code.