sub CheckBC {
    my $pid = open3 my $wh, my $rh, my $eh, "bc" or die;
    print $wh shift() . "\n";
    close $wh or die;
    my $throwResultAway = <$rh>;
    close $rh or die;
    my $error = <$eh>;
    close $eh or die;
    waitpid $pid, 0; # else forkbomb, zombies, etc.
    !$error;
}