GnuPG for pure DOS ?

[Peter Gutmann]

dnl <dnl at wanadoo.fr> writes:

>Is it very difficult to write a GnuPG 1.0 for DOS ?

You'd have to do it using a DOS extender, however this would probably require 
a bit of effort to get going, and since the end user base is likely to be 
small and the number of people who could do the port would be a minute subset 
of "small", it may take awhile to appear.  You've also got the RNG problems 
you mentioned, you really can't get good randomness under DOS unless you use 
external hardware (and even that's problematic given DOS's marginal support 
for things like serial I/O to an RNG) or a /dev/random type driver.

(This is from experience with my own code under DOS - once the app grows
 beyond a certain size you run into difficult territory due to the need to
 use DOS extenders, and some things like the RNG will never work properly).

>Is there a possibility to use GnuPG Win32 in pure DOS with a special TSR ?

Sure, that's easy.  From DOS, run the 'ntldr' program, this will install a
special TSR which allows you to run the Win32 GPG.  It's a general-purpose TSR
so you'll find you can run other programs (eg MS Office) under it as well.

Peter.