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    <p>So, if I've understand you correctly - you don't want to return control from function <code>spawn_workers</code> until each of worker is not stopped (and fetched a page)? If that - you may change your code in such way:</p> <pre><code>spawn_workers(Ids) -&gt; %% collect reference to each worker Refs = [ do_spawn(Id) || Id &lt;- Ids ], %% wait for response from each worker wait_workers(Refs). wait_workers(Refs) -&gt; lists:foreach(fun receive_by_ref/1, Refs). receive_by_ref(Ref) -&gt; %% receive message only from worker with specific reference receive {Ref, done} -&gt; done end. do_spawn(Id) -&gt; Ref = make_ref(), proc_lib:spawn_link(?MODULE, do_send_req, [Id, {self(), Ref}]), Ref. do_send_req(Id, {Pid, Ref}) -&gt; io:format("Requesting ID ~p ... ~n", [Id]), Result = (catch ibrowse:send_req(to_url(Id), [], get, [], [], 10000)), case Result of {ok, Status, _H, B} -&gt; io:format("OK -- ID: ~2..0w -- Status: ~p -- Content length: ~p~n", [Id, Status, length(B)]), %% send message that work is done Pid ! {Ref, done}; Err -&gt; io:format("ERROR -- ID: ~p -- Error: ~p~n", [Id, Err]), %% repeat request if there was error while fetching a page, do_send_req(Id, {Pid, Ref}) %% or - if you don't want to repeat request, put there: %% Pid ! {Ref, done} end. </code></pre> <p><strong>Edit:</strong></p> <p>I've noticed that your entry point (function <code>start</code>) returns control without waiting for all workers are end their tasks (because of you calling there <code>spawn</code>). If you want to wait there too - just do the similar trick:</p> <pre><code>start() -&gt; ibrowse:start(), Ref = make_ref(), proc_lib:spawn(?MODULE, send_reqs, [self(), Ref]), receive_by_ref(Ref). send_reqs(Pid, Ref) -&gt; spawn_workers(fetch_ids()), Pid ! {Ref, done}. </code></pre>
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    1. POHTTP crawler in Erlang
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    1. COHi stemm, played a lot with the code (see update in my original post) but something goes wrong. The crawler exits after fetching some of the files. Some of them are even fetched partially :(
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    2. CO@ctp, I've edited my answer. Also - how do you launch this code? From shell or in some other way?
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    3. COI've opened a Github repo with the project to collect the best practice approaches for such a task. And hopefully to help other ppl to get in contact with Erlang :) See http://stackoverflow.com/questions/12368270/http-crawler-in-erlang/12415123#12415123 (my last questions :))
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