ClibPDF
ClibPDF is an open source library which allows the programmer to create dynamically-generated PDF files directly from within a program's code.
Such applications include use in PHP.
According to http://de3.php.net/manual/en/ref.cpdf.php "ClibPDF support is deprecated and users are strongly encouraged to use an alternative, like Haru, PDFlib, or one of the available PHP alternatives."