my $listen_socket = IO::Socket::INET->new( Listen => 1,
                                    LocalPort => $tcpport,
                                    LocalHost => $tcphost,
                                    Proto => 'tcp',
                                    Blocking => 0,
    ) or die "Error during creation of listening socket: $!\n";

my $select = new IO::Select($listen_socket);

while (my @ready = $select->can_read)
{
    foreach my $connection (@ready)
    {
        if ($connection == $listen_socket)
        {
            my $client = $listen_socket->accept();
            $select->add($client);
            $data = <$connection>;
        }
        else
        {
            $data = <$connection>;
            if ($data)
            {
#macht irgendwas
            }

            else
            {
                 $select->remove($connection);
                close($connection);
            }
        }
    }
}