Re: Did rpc:call change behaviour in OTP-23.x or 24.x?

On Fri, Oct 8, 2021 at 7:10 PM Roger Lipscombe <[email protected]>
wrote:

> Specifically, I invoke the below function with rpc:call from an escript...
>
> frob(Parent, Etc) ->
>     link(Parent)
>     % do something interesting
>     ok.
>
> (condensed example)
>
> My escript dies with the following:
>
> {"init terminating in
> do_boot",{#Ref<0.2297215750.597688321.118580>,return,ok}}
> init terminating in do_boot ({,return,ok})
>
> If I unlink from the pid before returning, it's all good. This has
> worked perfectly since (afaict) R16, but broke at some point between
> OTP-22.x and OTP-24.x (we skipped OTP-23.x)
>
> We're using OTP-24.0.6
>

Yes this was intentionally changed in OTP 23 due to a performance
optimization. The process executing the actual call now terminates with an
exit reason not equal to normal while it previously used to terminate with
a normal exit reason. The rpc module has however never given any guarantees
about what happens with the process executing the call after the call
returns. Leaving a link to the process after the call is erroneous.

Regards,
Rickard
-- 
Rickard Green, Erlang/OTP, Ericsson AB