(PHP 4 >= 4.0.5, PECL pdflib >= 1.0.0)
PDF_add_launchlink — Add launch annotation for current page [deprecated]
$pdfdoc
   , float $llx
   , float $lly
   , float $urx
   , float $ury
   , string $filename
   )Adds a link to a web resource.
   This function is deprecated since PDFlib version 6,
   use PDF_create_action() with
   type=Launch and
   PDF_create_annotation() with
   type=Link instead.