option for viewing by recipient only

[Federico Grau]

Hello folks,

I have looked through the faq, searched the mailing list, and checked with the
RFC with no answer yet, so I come to you.

There is an option in pgp 6.5 (the 'free' unix command line version) that
allows a person encrypting the message to "mark it for viewing by recipient
only".  The command line option is "pgp -sem <message.txt> <recipient>".
Documentation of it can be found on page 39 of the _PGP Command Line - Freeare
User's Guide Version 6.5_.

Is there such an option for gpg?  Are there plans to implement such an option
in gpg... if not how much effort should it be?

thanks,
donfede


ps. If people were interested, I need this because I have an script sending
encrypted emails with credit card information to a person on a mac using some
version of pgp and eudora.  The recipient is able to decrypt the email with no
problem, however if the user is not careful (and as we know they too often are
not) they can save the UNENCRYPTED email... no only leaving sensitive
information on their machine, but also loosing/replacing the encrypted version
(so its not even a matter of deleting the sensitive unencrypted versions).

I understand that this "secure viewing option" is not failsafe and of course a
dedicated person can still make a permanent copy of the unencrypted text,
however it will make it more difficult for simple mistakes to happen.