<div dir="ltr">I hate to keep bugging with simple problems, but I'm stuck again. My FSM dosn't seem to be executing its first state. Here is my init function:<br><br><i>init(StartArgs) -><br> InitialState = case StartArgs of<br>
{store_chunk, Chunk} -><br> io:format("FSM Storing chunk...~n"),<br> {ok, storing_chunk, [Chunk]};<br> {get_chunk, Args} -><br> {ok, getting_chunk, Args};<br> Else -><br> %% @todo Add error logging here.<br>
io:format("Bad arg for FSM: ~p~n", [StartArgs])<br> end,<br> io:format("FSM Initial State: ~p~n", [InitialState]),<br> InitialState.</i><br><br>storing_chunk/2 is exported and I'm not getting any errors. Here is that function:<br>
<br><i>storing_chunk(_Event, [Chunk]) -><br> io:format("STATE: storing_chunk~n"),<br> case erlfs_store_lib:store_chunk() of<br> ok -><br> {next_state, notifying_tracker, Chunk};<br> {error, Reason} -><br>
%% @todo Add error logging here.<br> io:format("FSM Stopped: ~p~n", [Reason]),<br> {stop, {file, Reason}, Chunk#chunk.chunk_meta}<br> end.</i><br><br><div class="gmail_quote">On Wed, Aug 20, 2008 at 11:04 AM, Serge Aleynikov <span dir="ltr"><<a href="mailto:saleyn@gmail.com" target="_blank">saleyn@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">The error you reported earlier:<br>
<br>
{'EXIT', {badarg, [{erlang, apply,<br>
[erlfs_store_worker_fsm, start_link, {store_chunk, ...}]}]}}<br>
<br>
was a clear indication that erlang:apply(M,F,A) was called with A being a tuple rather than a list. If this still doesn't work after replacing tuple with a list in the second argument of the supervisor:start_child/2 call, this means that you probably have other issues in the erlfs_store_worker_fsm:start_link/1 itself.<br>
<br>
I can't say anything more without seeing a more detailed error report.<br><font color="#888888">
<br>
Serge</font><div><div></div><div><br>
<br>
Matt Williamson wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Yes, I saw that in the docs. What I was saying is that calling apply(M, F,<br>
A++List) =:= apply(M, F, List) when A =:= [].<br>
<br>
I did try your suggestion anyway with the same results.<br>
<br>
On Wed, Aug 20, 2008 at 9:54 AM, Serge Aleynikov <<a href="mailto:saleyn@gmail.com" target="_blank">saleyn@gmail.com</a>> wrote:<br>
<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
What is the arity of erlfs_store_worker_fsm:start_link function?<br>
<br>
Not quite sure what you mean by [] ++ 1 below.<br>
<br>
The supervisor:start_child/2 takes a list [term()] as the second parameter.<br>
Here's its docs:<br>
<br>
"If the case of a simple_one_for_one supervisor, the child specification<br>
defined in Module:init/1 will be used and ChildSpec should instead be an<br>
arbitrary list of terms List. The child process will then be started by<br>
appending List to the existing start function arguments, i.e. by calling<br>
apply(M, F, A++List) where {M,F,A} is the start function defined in the<br>
child specification."<br>
<br>
Note the A++List part.<br>
<br>
<br>
Matt Williamson wrote:<br>
<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I'm afraid that did not work. I am passing an empty list, and if I execute<br>
[] ++ 1 in the shell I get 1.<br>
<br>
On Wed, Aug 20, 2008 at 9:31 AM, Serge Aleynikov <<a href="mailto:saleyn@gmail.com" target="_blank">saleyn@gmail.com</a>><br>
wrote:<br>
<br>
Try starting it as:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
supervisor:start_child(erlfs_store_worker_sup, [{store_chunk, Chunk}])<br>
<br>
The simple_one_for_one strategy appends the arguments passed to<br>
supervisor:start_child/2 to the list of args specified in the<br>
supervisor's<br>
spec.<br>
<br>
Serge<br>
<br>
Matt Williamson wrote:<br>
<br>
Hello,<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I am starting a gen_fsm with<br>
supervisor:start_child(erlfs_store_worker_sup,<br>
{store_chunk, Chunk}) but I get the following error:<br>
<br>
{error,<br>
{'EXIT',<br>
{badarg,<br>
[{erlang,<br>
apply,<br>
[erlfs_store_worker_fsm,<br>
start_link,<br>
{store_chunk,<br>
{chunk,<br>
{chunk_meta,<br>
{file_meta,<br>
"test123",<br>
"test.txt",<br>
0,<br>
"text/plain",<br>
{{0,1,1},{0,0,0}}},<br>
0,<br>
0,<br>
[]},<br>
<<"Hello world!">>}}]},<br>
{supervisor,do_start_child_i,3},<br>
{supervisor,handle_call,3},<br>
{gen_server,handle_msg,6},<br>
{proc_lib,init_p,5}]}}}<br>
<br>
I've been trying to figure it out for a while, but I am having a hard<br>
time.<br>
Here is the Child Spec in the supervisor (erlfs_store_worker_sup):<br>
<br>
init(Args) -><br>
WorkerSpec = {erlfs_store_worker_fsm, {erlfs_store_worker_fsm,<br>
start_link, []},<br>
temporary, 2000, worker, [erlfs_store_worker_fsm]},<br>
{ok,{{simple_one_for_one, 0, 1}, [WorkerSpec]}}.<br>
<br>
<br>
<br>
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</blockquote></blockquote></blockquote></blockquote>
<br>
</blockquote>
<br>
</div></div></blockquote></div><br></div>