Ejemplo de mensajes entre procesos

ping_pong.erl

-module(ping_pong). % Nombre del modulo
-compile(export_all). % Esto hace todas las funciones publicas fuera del modulo

ping(0, Pong_PID) ->
    Pong_PID ! finished,
    io:format("ping finished~n", []);
ping(N, Pong_PID) ->
    Pong_PID ! {ping, self()},
    receive
        pong ->
            io:format("Ping received pong~n", [])
    end,
    ping(N - 1, Pong_PID).
pong() ->
    receive
        finished ->
            io:format("Pong finished~n", []);
        {ping, Ping_PID} ->
            io:format("Pong received ping~n", []),
            Ping_PID ! pong,
            pong()
    end.
start() ->
    Pong_PID = spawn(mess_pass, pong, []),
    spawn(mess_pass, ping, [3, Pong_PID]).