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|
-module(e).
-behaviour(gen_server).
%% External exports
-export([start_link/0]).
-export([hello/0]).
%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
code_change/3]).
-record(state, {}).
%%%----------------------------------------------------------------------
%%% API
%%%----------------------------------------------------------------------
start_link() ->
gen_server:start_link({local, myserver}, myserver, [], []).
hello() ->
gen_server:call(myserver, hello).
%%%----------------------------------------------------------------------
%%% Callback functions from gen_server
%%%----------------------------------------------------------------------
%%----------------------------------------------------------------------
%% Func: init/1
%% Returns: {ok, State} |
%% {ok, State, Timeout} |
%% ignore |
%% {stop, Reason}
%%----------------------------------------------------------------------
init([]) ->
{ok, #state{}}.
%%----------------------------------------------------------------------
%% Func: handle_call/3
%% Returns: {reply, Reply, State} |
%% {reply, Reply, State, Timeout} |
%% {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, Reply, State} | (terminate/2 is called)
%% {stop, Reason, State} (terminate/2 is called)
%%----------------------------------------------------------------------
handle_call(Request, From, State) ->
Reply = case Request of
char ->
$B;
integer ->
17;
float ->
32.76;
string ->
"hi there";
atom ->
hello;
block ->
begin
a,
b
end;
binary ->
<<1, 2, 3>>
end,
{reply, Reply, State}.
%%----------------------------------------------------------------------
%% Func: handle_cast/2
%% Returns: {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, State} (terminate/2 is called)
%%----------------------------------------------------------------------
handle_cast(Msg, State) when atom(Msg) ->
{noreply, State};
handle_cast(Msg, State) when binary(Msg) ->
{noreply, State};
handle_cast(Msg, State) when not is_tuple(Msg), not is_list(Msg) ->
{noreply, State};
handle_cast(Msg, State) when float(Msg) ->
{noreply, State};
handle_cast(Msg, State) when function(Msg) ->
{noreply, State};
handle_cast(Msg, State) when integer(Msg) ->
{noreply, State};
handle_cast(Msg, State) when list(Msg) ->
{noreply, State};
handle_cast(Msg, State) when number(Msg) ->
{noreply, State};
handle_cast(Msg, State) when pid(Msg) ->
{noreply, State};
handle_cast(Msg, State) when port(Msg) ->
{noreply, State};
handle_cast(Msg, State) when reference(Msg) ->
{noreply, State};
handle_cast(Msg, State) when tuple(Msg) ->
{noreply, State}.
%%----------------------------------------------------------------------
%% Func: handle_info/2
%% Returns: {noreply, State} |
%% {noreply, State, Timeout} |
%% {stop, Reason, State} (terminate/2 is called)
%%----------------------------------------------------------------------
handle_info(Info, State) ->
{noreply, State}.
%%----------------------------------------------------------------------
%% Func: terminate/2
%% Purpose: Shutdown the server
%% Returns: any (ignored by gen_server)
%%----------------------------------------------------------------------
terminate(Reason, State) ->
ok.
%%----------------------------------------------------------------------
%% Func: code_change/3
%% Purpose: Convert process state when code is changed
%% Returns: {ok, NewState}
%%----------------------------------------------------------------------
code_change(OldVsn, State, Extra) ->
{ok, State}.
%%%----------------------------------------------------------------------
%%% Internal functions
%%%----------------------------------------------------------------------
|
