The problem i'm facing is to create a libary file with binding to ruby on windows platform

i’v checked about pdflib, and the good news are that you are right and
it can be installed locally for a certain rails project, it works when
you copy a libary file ("pdflib.so ") into the vendors directory.
there are two versions of pdflib , one that costs money , and the lite
version which is free to use.
i tried using a demo of the full version and it’s working but with a
“demo stamp” all over the pdf document.
the demo version comes with a libary file (.so file) and the lite
version doesn’t, and i havnen’t figured out how to create one yet !
the problem i’m facing is to create a libary file with binding to ruby
on windows platform ,
the only close tutorial or help docs i found was creating ruby binding
file on linux platform .