server1.erl

-module(server1).
-export([start/2, rpc/2]).

start(Name, Mod) ->
  register(Name, spawn(fun() -> loop(Name, Mod, Mod:init()) end)).

rpc(Name, Request) ->
  Name ! {self(), Request},
  receive
    {Name, Response} -> Response
  end.

loop(Name, Mod, State) ->
  receive
    {From, Request} ->
      {Response, State1} = Mod:handle(Request, State),
      From ! {Name, Response},
      loop(Name, Mod, State1)
  end.