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Does the error in gen_server also terminate the calling process?

My gen_server contains a method similar to this:

handle_call(error, From, State) ->
    io:format("Inside the handle_call error~n"),
    1/0.

It provides a function start(not start_link):

start() ->
    gen_server:start({local, ?MODULE}, ?MODULE, [], []).

normal_call() ->
    gen_server:call(?MODULE, {normal}).

error_call() ->
    gen_server:call(?MODULE, error).

I call the function startfrom the shell:

c(some_module).
some_module:start().

Then I call an error call that terminates the server process due to a zero delimited error, but also terminates the shell (the calling process). I do not understand why? They are not connected, but still the shell restarts a new pid. Is this the expected behavior of gen_server, or am I doing something wrong?

Updated: It still doesn't work to help me post the full code.

-module(some_test).
-behaviour(gen_server).
-compile(export_all).

%% api functions, can be directly used by the user

start() ->
    gen_server:start({local, ?MODULE}, ?MODULE, [], []).

normal_call() ->
    gen_server:call(?MODULE, normal, infinity).

error_call() ->
    gen_server:call(?MODULE, error, infinity).

%% service specific function shoule not be call directly

init(_) ->
    io:format("Inside the init ( ~p )~n", [self()]),
    io:format("Inside the init...~n"),
    {ok, nil}.

handle_call(normal, _, _) ->
    io:format("Inside the handle_call normal~n"),
    {reply, ok, nil};

handle_call(error, _, nil) ->
    io:format("Inside the handle_call error~n"),
    1/0.

terminate(Reason, _) ->
    io:format("Inside the terminate~p~n", [Reason]).

%% just to complete

handle_info(_, _) ->
    {noreply, nil}.

handle_cast(_, _) ->
    {noreply, nil}.

code_change(_, _, _) ->
    {ok, nil}.

%% a single test function that prove that called process was removed immeditely, did not wait for 5 seconds

test_function() ->
    io:format("Id is : ~p~n", [self()]),
    ?MODULE:start(),
    ?MODULE:normal_call(),
    ?MODULE:error_call(),
    io:format("Id is : ~p~n", [self()]).   %% never reached :(

and for starters, I used this: -

c(some_test).
some_test:test_function().

and got the result: -

20> some_test:test_function().
Id is : <0.84.0>
Inside the init ( <0.92.0> )
Inside the init...
Inside the handle_call normal
Inside the handle_call error
Inside the terminate{badarith,
                        [{some_test,handle_call,3,
                             [{file,"some_test.erl"},{line,29}]},
                         {gen_server,try_handle_call,4,
                             [{file,"gen_server.erl"},{line,629}]},
                         {gen_server,handle_msg,5,
                             [{file,"gen_server.erl"},{line,661}]},
                         {proc_lib,init_p_do_apply,3,
                             [{file,"proc_lib.erl"},{line,240}]}]}

=ERROR REPORT==== 3-Dec-2015::18:36:22 ===
** Generic server some_test terminating
** Last message in was error
** When Server state == nil
** Reason for termination ==
** {badarith,[{some_test,handle_call,3,[{file,"some_test.erl"},{line,29
              {gen_server,try_handle_call,4,
                          [{file,"gen_server.erl"},{line,629}]},
              {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,6
              {proc_lib,init_p_do_apply,3,
                        [{file,"proc_lib.erl"},{line,240}]}]}
** exception exit: {{badarith,
                        [{some_test,handle_call,3,
                             [{file,"some_test.erl"},{line,29}]},
                         {gen_server,try_handle_call,4,
                             [{file,"gen_server.erl"},{line,629}]},
                         {gen_server,handle_msg,5,
                             [{file,"gen_server.erl"},{line,661}]},
                         {proc_lib,init_p_do_apply,3,
                             [{file,"proc_lib.erl"},{line,240}]}]},
                    {gen_server,call,[some_test,error,infinity]}}
     in function  gen_server:call/3 (gen_server.erl, line 212)
     in call from some_test:test_function/0 (some_test.erl, line 51)
21>

since we can see that the last line after some_test: error_call () is never called ?? because the calling process is also terminating ??

+3
1

gen_server: call/2,3 - . , , gen_server . gen_server . , , .

, , 5 . , 5000 ( , ). infinity - , , .

[UPDATE: , , , . - , .]

, , gen_server: cast/2. :

handle_cast(error, State) ->
    io:format("Inside the handle_cast error~n"),
    1/0.

; , . , .

, Erlang, cast call, (- ), , .

- , . . , . some_tester, , , , . :

-module(some_tester).
-compile(export_all).

start() ->
    gen_server:start({local, ?MODULE}, ?MODULE, [], []).

relay(Nature, Message) ->
    gen_server:cast(?MODULE, {Nature, Message}).


init(State) ->
    ok = z("Starting..."),
    {ok, State}.

handle_call(Message, From, S) ->
    ok = z("Received ~tp from ~tp", [Message, From]),
    {reply, ok, S}.

handle_cast({cast, Message}, S) ->
    ok = some_test:cast(Message),
    {noreply, S};
handle_cast({call, Message}, S) ->
    ok = z("Sending call with ~tp", [Message]),
    Reply = some_test:normal_call(Message),
    ok = z("Received ~tp as reply", [Reply]),
    {noreply, S};
handle_cast({infinite, Message}, S) ->
    ok = z("Sending infinite with ~tp", [Message]),
    Reply = some_test:infinite_call(Message),
    ok = z("Received ~tp as reply", [Reply]),
    {noreply, S};
handle_cast(Message, S) ->
    ok = z("Unexpected ~tp", [Message]),
    {noreply, S}.

some_test:

start() ->
    gen_server:start({local, ?MODULE}, ?MODULE, [], []).

normal_call(Message) ->
    gen_server:call(?MODULE, Message).

infinite_call(Message) ->
    gen_server:call(?MODULE, Message, infinity).

cast(Message) ->
    gen_server:cast(?MODULE, Message).

% ...

handle_call(normal, _, S) ->
    io:format("Inside the handle_call normal~n"),
    {reply, ok, S};
handle_call(error, _, S) ->
    io:format("Inside the handle_call error~n"),
    {reply, 1/0, S};
handle_call(bad_reply, _, S) ->
    io:format("Inside the handle_call error~n"),
    foo;
handle_call(Message, From, S) ->
    io:format("Received ~tp from ~tp~n", [Message, From]),
    {reply, ok, S}.

handle_cast(error, S) ->
    io:format("Bad arith: ~tp~n", [1/0]),
    {noreply, S};
handle_cast(Message, S) ->
    io:format("Received ~tp~n", [Message]),
    {noreply, S}.

. self() flush():

1> c(some_test).
some_test.erl:31: Warning: this expression will fail with a 'badarith' exception
some_test.erl:32: Warning: variable 'S' is unused
some_test.erl:40: Warning: this expression will fail with a 'badarith' exception
{ok,some_test}
2> c(some_tester).
{ok,some_tester}
3> {ok, Test} = some_test:start().
Inside the init ( <0.45.0> )
Inside the init...
{ok,<0.45.0>}
4> {ok, Tester} = some_tester:start().
<0.47.0> some_tester: Starting...
{ok,<0.47.0>}
5> monitor(process, Test).
#Ref<0.0.2.178>
6> monitor(process, Tester).
#Ref<0.0.2.183>
7> self().
<0.33.0>
8> some_tester:relay(call, foo).
<0.47.0> some_tester: Sending call with foo
ok
Received foo from {<0.47.0>,#Ref<0.0.2.196>}
<0.47.0> some_tester: Received ok as reply
9> some_tester:relay(cast, bar).
Received bar
ok
10> some_tester:relay(call, error).
<0.47.0> some_tester: Sending call with error
ok
Inside the handle_call error
Inside the terminate{badarith,
                        [{some_test,handle_call,3,
                             [{file,"some_test.erl"},{line,31}]},
                         {gen_server,try_handle_call,4,
                             [{file,"gen_server.erl"},{line,629}]},
                         {gen_server,handle_msg,5,
                             [{file,"gen_server.erl"},{line,661}]},
                         {proc_lib,init_p_do_apply,3,
                             [{file,"proc_lib.erl"},{line,240}]}]}
Inside the terminate{{badarith,
                         [{some_test,handle_call,3,
                              [{file,"some_test.erl"},{line,31}]},
                          {gen_server,try_handle_call,4,
                              [{file,"gen_server.erl"},{line,629}]},
                          {gen_server,handle_msg,5,
                              [{file,"gen_server.erl"},{line,661}]},
                          {proc_lib,init_p_do_apply,3,
                              [{file,"proc_lib.erl"},{line,240}]}]},
                     {gen_server,call,[some_test,error]}}
11> 
=ERROR REPORT==== 3-Dec-2015::22:52:17 ===
** Generic server some_test terminating 
** Last message in was error
** When Server state == nil
** Reason for termination == 
** {badarith,[{some_test,handle_call,3,[{file,"some_test.erl"},{line,31}]},
              {gen_server,try_handle_call,4,
                          [{file,"gen_server.erl"},{line,629}]},
              {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,661}]},
              {proc_lib,init_p_do_apply,3,
                        [{file,"proc_lib.erl"},{line,240}]}]}

=ERROR REPORT==== 3-Dec-2015::22:52:17 ===
** Generic server some_tester terminating 
** Last message in was {'$gen_cast',{call,error}}
** When Server state == []
** Reason for termination == 
** {{{badarith,[{some_test,handle_call,3,[{file,"some_test.erl"},{line,31}]},
                {gen_server,try_handle_call,4,
                            [{file,"gen_server.erl"},{line,629}]},
                {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,661}]},
                {proc_lib,init_p_do_apply,3,
                          [{file,"proc_lib.erl"},{line,240}]}]},
     {gen_server,call,[some_test,error]}},
    [{gen_server,call,2,[{file,"gen_server.erl"},{line,204}]},
     {some_tester,handle_cast,2,[{file,"some_tester.erl"},{line,24}]},
     {gen_server,try_dispatch,4,[{file,"gen_server.erl"},{line,615}]},
     {gen_server,handle_msg,5,[{file,"gen_server.erl"},{line,681}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,240}]}]}

11> self().
<0.33.0>
12> flush().
Shell got {'DOWN',#Ref<0.0.2.178>,process,<0.45.0>,
              {badarith,
                  [{some_test,handle_call,3,
                       [{file,"some_test.erl"},{line,31}]},
                   {gen_server,try_handle_call,4,
                       [{file,"gen_server.erl"},{line,629}]},
                   {gen_server,handle_msg,5,
                       [{file,"gen_server.erl"},{line,661}]},
                   {proc_lib,init_p_do_apply,3,
                       [{file,"proc_lib.erl"},{line,240}]}]}}
Shell got {'DOWN',#Ref<0.0.2.183>,process,<0.47.0>,
              {{badarith,
                   [{some_test,handle_call,3,
                        [{file,"some_test.erl"},{line,31}]},
                    {gen_server,try_handle_call,4,
                        [{file,"gen_server.erl"},{line,629}]},
                    {gen_server,handle_msg,5,
                        [{file,"gen_server.erl"},{line,661}]},
                    {proc_lib,init_p_do_apply,3,
                        [{file,"proc_lib.erl"},{line,240}]}]},
               {gen_server,call,[some_test,error]}}}
ok

.

+5

Source: https://habr.com/ru/post/1618407/

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