## This is what I think is needed beforehand :
open( TIDY, "html-tidy $commandline|") or die "Couldn't spawn html-tid
+y : $!\n";

my @output;
@output = <TIDY>;

## Here begins their code :
if (close(TIDY) == 0) {
  my $exitcode = $? >> 8;
  if ($exitcode == 1) {
    printf STDERR "tidy issued warning messages\n";
  } elsif ($exitcode == 2) {
    printf STDERR "tidy issued error messages\n";
  } else {
    die "tidy exited with code: $exitcode\n";
  }
} else {
  printf STDERR "tidy detected no errors\n";
}
[download]

my @output = qx(html-tidy $commandline);
my $exitcode = $? >> 8;
if ($exitcode == 1) {
  printf STDERR "tidy issued warning messages\n";
} elsif ($exitcode == 2) {
  printf STDERR "tidy issued error messages\n";
} else {
  die "tidy exited with code: $exitcode\n";
}
[download]

Wrapping it up, unless you tell us a really convincing reason why html-tidy is not possible (and with not possible I also mean putting html-tidy into a Perl script, writing it out to /tmp, starting it there and afterwards deleting the file again), I'll stick with this solution :-)

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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