Hi 1nickt,

To get the default behavior, one can specify the on_post_exit option. The status code for __DIE__ is 255 typically.

MCE::Loop->init(
    max_workers => 2, chunk_size => 1, user_begin => sub {
        $SIG{'INT'} = sub {
            my $signal = shift;
            say "Hello from $signal: $$";
            MCE->exit(0);
        };
    },
    on_post_exit => sub {
        my ($mce, $e) = @_;
        if ($e->{status} == 255) {
            MCE::Signal::stop_and_exit('__DIE__');
        }
    }
);
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More info on on_post_exit is found here. The die handler for MCE workers is found inside MCE::Core::Worker ( ~ line 649 ). I cannot change the MCE->exit(...) line to MCE::Signal::stop_and_exit('__DIE__'). That will break scripts where MCE is called from inside an eval block.

local $SIG{__DIE__} = sub {

   ...

   local $SIG{__DIE__}; local $\ = undef;
   my $_die_msg = (defined $_[0]) ? $_[0] : '';
   print {*STDERR} $_die_msg;

   $self->exit(255, $_die_msg, $self->{_chunk_id});
};
[download]

TODO: When on_post_exit is not specified, have MCE workers abort input due to uncaught exception. Revisit eval. I was unable to get $@ to stick at the manager level. To make this work, I need to call die with the error obtained from the worker at the manager level.

eval { mce_loop { ... } @input };

# TODO: Today, $@ is not set at the manager level.
# Thus, the eval block succeeds. Will fix this.

if ( $@ ) {
    ...
}
[download]

Fortunately, one has control with the on_post_exit handler on what to do: e.g. restart_worker, stop_and_exit.