From pdftk man page, I should be able to protect a pdf document from content copy, printing, snapshots with:
pdftk 1.pdf output 1.128.pdf owner_pw foopass
But it fails, I can do any of them !
I have also tested qpdf:
qpdf --encrypt "" "foopass" 128 --extract=n -- 1.pdf 1.128.pdf
With the same failing result.
And also a commercial pdf tool with the same failing result.
I remember I could successfully protect pdf files with pdftk in the past with this command.
I am on debian jessie.
Have I missed something? Other solutions on Linux are welcome, but with 3 sproducts failing, it liiks like I have a problem with my setup.
I don't want to use a user password (confidentiality), just a owner password (protection).