Date   : Thu, 21 Jan 1988 07:59:22 MDT
From   : ZUC02AA%WYOCDC1.BITNET@CUNYVM.CUNY.EDU
Subject: Encryption/Decryption

(I hope this is not inappropiate for this list...)

I have played a couple of INFOCOM's CPM games and noticed their use of data
files ('.DAT' extensions) that evidently make use of some sort of encryption.
This arouses my curiosity.  Using DDT (and another dis-assembler whose name I
forget) I am unable to tell just what they did.  I am curious for the sake of
being curious and also because it sounds like something I'd like to use myself.
I've looked at a couple of sources on encryption but they don't exactly tell
things from a CPM viewpoint.  So - If someone has the time,  is there a source
reference,  a dis-assembler (best of all),  a piece of code,  etc.,  on this
topic that one could clue me in on?  (I sure hope this is nothing propietary!)
Bear in mind that modern ages have overtaken me - I use an MSDOS machine at
work and I fear I don't know my Kaypro II and Z80 assembler as well as I used
to.  Thanks in advance.

Rich Travsky
ZUC02AA@WYOCDC1.BITNET

P.S.  I am not on this list so please send to me directly.

P.P.S Note I'm on BITNET and can't (*sigh*) FTP anything.