use threads;
use threads::shared;

our $SHARED_DATA : shared;
our @threads = (); # threads
our $FINISHED : shared = 0; # for simulation state

main();

main (
    process()
)


init(

    for () {
       push @threads, threads->new (\&Foo::run()...);
    }
)

process(
    init();
    finish();
)
sub finish {
#    our (@threads);
    
    { lock $FINISHED; $FINISHED = 1; }
    $_->join for @threads;
}


###################
# my class
###################
package Foo;
use threads;
use threads::shared;

sub new {}

sub run {

    dothings()
    {lock $FINISHED; return if $FINISHED;}
}

sub dothings {
    lock ($SHARED_DATA);
    # ...
}