Erlang application problem

I try to write application to my Erlang program.

I have test_app.erl:

-module(test_app).

-behaviour(application).

%% Application callbacks
-export([start/2, stop/1]).

start(_Type, _StartArgs) ->
    test_sup:start_link().

stop(_State) ->
  ok.

And .app file:

{application, test,
  [{description, "test system."},
  {vsn, "1.0"},
  {modules, [test_app, test_sup, fsm]},
  {registered, [test_sup, fsm]},
  {applications, [kernel, stdlib]},
  {mod, {test_app, []}}
]}.

When i try to start application:

application:start(test).

I get error:

=INFO REPORT==== 18-Feb-2011::19:38:53 ===
    application: test
    exited: {bad_return,
                {{test_app,start,[normal,[]]},
                 {'EXIT',
                     {undef,
                         [{test_sup,start_link,[[]]},
                          {test_app,start,2},
                          {application_master,start_it_old,4}]}}}}
    type: temporary
{error,{bad_return,{{test_app,start,[normal,[]]},
                    {'EXIT',{undef,[{test_sup,start_link,[[]]},
                                    {test_app,start,2},
                                    {application_master,start_it_old,4}]}}}}}

What'开发者_开发知识库s wrong? How can i fix it?

If i make in eshell:

test_app:start(normal, []).

Than all works.

Thank you.

---

I suppose this might be caused by not loading the [proper] .beam. Ensure that all modules are in the same directory, or try to use -pa key to erl(1), e. g.:

$ erl -pa ../ebin
1> application:start(test).
...