Don't apologize - your English is far superior to my Polish (thank you, Google Translate, for helping me identify that as Polish :) )

I think all you need to do is add the following lines just below your last "use" statement:

use Config;

# copied from perldoc Config
my %sig_num;
my @sig_name;
unless($Config{sig_name} && $Config{sig_num}) {
    die "No sigs?";
} else {
    my @names = split ' ', $Config{sig_name};
    @sig_num{@names} = split ' ', $Config{sig_num};
    foreach (@names) {
        $sig_name[$sig_num{$_}] ||= $_;
    }   
}

# ignore child signals, automatically reaping child processes
$SIG{$sig_num{CHLD}} = 'IGNORE';
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Of course, you'll have to test this, but I think it might solve your issue.