[erlang-questions] spawn_link/2 behaviour

[Avinash Dhumane]

Hello,

I have following test program (on Windows):

D:\Balin\Algo_v6\v0.5>type my_test.erl
-module(my_test).
-export([start/0]).

start() ->
  register(?MODULE,
    spawn(fun() ->
      init(),
      local_loop()
    end)).

init() ->
  spawn_link('feed@REDACTED',
    fun() ->
      register(?MODULE, self()),
      remote_loop()
    end),

  spawn('feed@REDACTED',
    fun() ->
      timer:sleep(timer:seconds(5)), % wait till the above process is
registered
      ?MODULE ! hello,
      ?MODULE ! world,
      ?MODULE ! stop
    end).

remote_loop() ->
  receive
    X ->
     {?MODULE, 'algo@REDACTED'} ! X,
     remote_loop()
  end.

local_loop() ->
  receive
    stop ->
      io:format("stopped~n");
    X ->
      io:format("~p~n", [X]),
      local_loop()
  end.

D:\Balin\Algo_v6\v0.5>

Then, I start 2 nodes, as follows:

D:\Balin\Algo_v6\v0.5>start erl -name algo@REDACTED

D:\Balin\Algo_v6\v0.5>start erl -name feed@REDACTED

On the 'algo@REDACTED' node, I run the program as follows:

Eshell V7.0  (abort with ^G)
(algo@REDACTED)1> rpc:call('feed@REDACTED', erlang, whereis, [my_test]).
undefined
(algo@REDACTED)2> my_test:start().
true
(algo@REDACTED)3> hello
(algo@REDACTED)3> world
(algo@REDACTED)3> stopped
(algo@REDACTED)3> rpc:call('feed@REDACTED', erlang, whereis, [my_test]).
<6755.43.0>
(algo@REDACTED)4>

The messaging works as I expected. However, the process registered as
'my_test' on the node 'feed@REDACTED' does not terminate. I expected it
to terminate since I started it using spawn_link/2 from the calling process
on 'algo@REDACTED' which terminates after receiving the 'stop' message.

It keeps running, as is observed on the node 'feed@REDACTED':

Eshell V7.0  (abort with ^G)
(feed@REDACTED)1> whereis(my_test).
<0.43.0>
(feed@REDACTED)2>

What is wrong with the setup done in the test program above that the linked
process on another node does not terminate?

Please advise.

Thank you.

Avinash
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