Johannes Wiedersich wrote: > Merciadri Luca wrote: > > Johannes Wiedersich wrote: > >> Why would an > >> honest soul ever allow information to be read, but not printed? > >> > > To maintain honesty? An honest soul (i.e. me, here) has to send some > > data to some dishonest person. > > The problem is: either you give data to some dishonest person or you > don't give that data to some dishonest person. Tertium non datur. Yes, but there are some nuances. Let's take my example: how would you have done this? You need to transmit the document, but the receivers are sufficiently dishonest to print it and to claim they are the authors. > > >> Even with acroread it is possible to print screenshots of the > documents. > >> Might be a pain to reconstruct a multipage document, but not > impossible. > >> > > I know, and we all know this. But this needs some determination, because > > it needs some time. And when such problems arise, one often thinks (or > > should, at least, think) `Do I really need to copy this using that > > painful way, to bypass some limitation which is actually imposed to me > > by an honest person?' This is another aspect of security. There are the > > technical means, and all the infringements which can be done. But, > > sometimes, `le jeu n'en vaut pas la chandelle.' > > FWIW, if you'd like to rely on such a scheme for security by obstacles, > you'd have to use something else than pdf. pdf's scheme is broken. > That's all. And what do you advice? > > The reason that it is broken for pdfs is that the specifications for pdf > are freely available, and thus alternative pdf readers have been > developed. Your scheme would require closed specifications and closed > software to work. This list, however, is all about free software. Yes, but if I had to use closed specs. with closed softwares, I would have to pay, and what about paying for your own rights??
-- Merciadri Luca See http://www.student.montefiore.ulg.ac.be/~merciadri/ I use PGP. If there is an incompatibility problem with your mail client, please contact me.
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