$kernel->yield('keepalive', $io_wheel->ID, $kernel);

##</code><code>##

  keepalive => sub {
      my ( $io_wheel_id, $kernel, $heap ) = @_[ ARG0, KERNEL ];
      return unless exists $heap->{clients}{$io_wheel_id};
      $heap->{clients}{$io_wheel_id}->put("keepalive");
      $kernel->delay( 'keepalive' => 10, $io_wheel_id );
  },

##</code><code>##

sub delete_client {
  my ($kernel, $heap, $io_wheel_id) = @_;
  delete $heap->{clients}{$io_wheel_id};
  $kernel->delay(keepalive => undef);
}

##</code><code>##

        on_connect_error => sub {
            # Handle client error, including disconnect.
            my $wheel_id = $_[ARG3];
            delete_client(@_[KERNEL, HEAP], $wheel_id);
        },