my $username = user_input('Username: ');
 my $password = user_input('Password: ');

 my $ua = new LWP::UserAgent;
 my $xml = $ua->get(
  'http://www.perlmonks.org/index.pl?node_id=227820&' .
  'op=login&user=' . uri_escape($username) . '&passwd=' .
  uri_escape($password)
 );
 undef $password; # deny access to $password later on
 deny_access('User authentication failed.')
  unless grep { /set\-cookie/i } keys %{$xml->{_headers}};