Re: Self-destructing documents

["Collins, Darren DA" <Collins -dot- Darren -dot- DA -at- BHP -dot- COM -dot- AU>]

John,

The easiest way to do this would probably be to write a viewing
application in a language like MS Visual Basic or Borland C++ Builder.
Just create a form with a rich text field (or postscript viewer if you
want to get fancy), copy your document into it, write some code to
disable it after x days, compile it into a single executable file, and
distribute it.

The text is then embedded in the executable and so not easily
retreivable by your users.  You could probably set the properties of the
text field on the form so that they can't select text and copy it - they
would have to retype it if they really want to keep it.

If you want more information, feel free to email me.

Darren Collins
Computer Engineer, Blast Furnaces
BHP Integrated Steel Division
Port Kembla, Australia

-----Original Message-----
From: John Cornellier [mailto:cornelli -at- CLAMART -dot- SRPC -dot- SLB -dot- COM]
Sent: Tuesday, 09 June 1998 2:49 AM
To: TECHWR-L -at- LISTSERV -dot- OKSTATE -dot- EDU
Subject: Self-destructing documents


Hello

I have a PDF file I want to sell for a limited period, i.e. you use it
for 30 days and then it turns into a pumpkin or become otherwise
unreadable. The medium is PDF.

This would be like a shareware program that becomes unusable after a
trial period. Is this realistic? Obviously anyone who really wants to
copy the material will do it. They can retype it from the screen if
they're so inclined. In any case I'd like to hear from anyone who has
implemented or considered implementing what I describe above, whether
with PDF or not.

Thanks
John Cornellier
tech writer, Paris France