1> test_event_call:start_link().
{ok,<0.85.0>}
2> test_event_call:start_event().
{error,{ok,{child,undefined,test_event_proc,
                  {test_event,start,[]},
                  transient,200000,worker,
                  [test_event]}}}

-module(test_event_call).
-behaviour(supervisor).
-export([start_link/0, start_event/0, init/1]).

start_link() ->
    supervisor:start_link({local, ?MODULE},
                          ?MODULE, []).

start_event() ->
    supervisor:start_child(?MODULE, {test_event_proc,
                                     {test_event, start, []},
                                     transient, 200000, worker, [test_event]}).

init(_Args) ->
    {ok, {{one_for_one, 1, 5}, []}}.

-module(test_event).
-behaviour(gen_event).
-export([init/1, handle_event/2, handle_call/2, handle_info/2, terminate/2, code_change/3]).


-export([start/0, log_fun/2]).

start() ->
    {ok, _Pid} = gen_event:start_link({local, ?MODULE}),
    gen_event:add_handler(?MODULE, ?MODULE, []).