while ($input = <$client>) {
  $input =~ s/\r\n//g; # kill CR and NL chars
  $input =~ /^Content-Length: (\S*)/i && ($content_length=$1);

  ... more code ....

  ## find a blank line and we already have the content length then read the POST data
  if (length($input) == 0 && $content_length > 0) {
     $client->recv($form_content,$content_length);
  }

}