- permissions is an array with values taken from the following list:
copy, print, modify, annot-forms
If a value is present it means that the permission is granted
- If a user password is set, user will be prompted before document is opened
- If an owner password is set, document can be opened in privilege mode with no
restriction if that password is entered
public SetProtection ( $permissions = [], $user_pass = '', $owner_pass = null ) |