Getting PDF version installed on client machine

Hi,

We have a functionality to do auto print in our application, because of security reason, 8.1.2 version confirmation is required to print a PDF. As suggested in the forum, i used trusted fucntion and its working fine. However i need to ask client to install the trusted .js file in their machine. Currently only few clients are using 8.1.2, so we send file to only to them. In my code i need to check the PDF version, so i can call trusted function only when version is 8.1.2 and above. Please provide me your suggestion.

Note: platform is windows.

Thanks
Ramesh