On Mon, Mar 19, 2012 at 17:51, luigi scarso wrote:
I'm not sure about it, but I'm tempted to believe that digitally signing PDFs might be one of "forbidden" functionality that requires you to buy a licence for Acrobat. Why ? As long it is described in the ISO standard, it can be implemented in mkiv (easily is another question).
As I said: I'm not sure whether or not it is legal to implement it or not. There seem to be two separate issues: (a) creating a document that others users will be able to fill in and sign (b) signing your own document Martin usually knows the legal issues better. I'm not sure about the exact legal state and I'm not sure where to check it without getting lost in "hundreds" of pages of EULA or other documents, but (b) is described in PDF Reference Manual (http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/devnet/pdf/pdf...) in Chapter 12 and cannot be any more complicated to implement than all other PDF features that Hans, Taco or Hartmut ever implemented. Out of curiosity: is inability to create password-protected PDF files with pdfTeX/LuaTeX due to legal issues or due to nobody caring enough to implement it? Mojca