Date   : Wed, 09 Dec 1987 03:37:11 GMT
From   : rochester!ciaraldi@bbn.com (Mike Ciaraldi)
Subject: Re: running DU on a CPM3 system (or MP/M!!)

In article <8712082023.AA08132@newton.arpa> bridger%rcc@RAND-UNIX.ARPA
(Bridger Mitchell) writes:
>DU  uses direct bios file i/o to access disk sectors.  It's an
>example of a program that needs repackaging to run under cp/m 3.
>To use it, get CPM2RSX (or similarly-named RSX) and use the
>CP/M 3 utility to encapsulate a COM file with that RSX.
>
>That particular RSX converts  cp/m 2.2-style direct bios io calls
>to cp/m 3 calls via the dos AND provides full physical->logical
>sector deblocking.


Am I missing something?  The newest version of DU I have seen,
version 8.9 (from sometime in 1984), is supposed to check whether it
is running on CP/M 1.x, 2.x, or 3.x, and adjust accordingly.
For example, it uses direct BIOS calls for 1 and 2, but
uses BDOS function 50 to do its BIOS calls in 3.

Meanwhile, I am in the process of converting DU to run on my MP/M system.
Has anyone already done this?

BTW, I assume we are talking about the same "DU"--the disk utility
which lets you read, write, and modify any sector on the disk.


Mike Ciaraldi
arpa:  ciaraldi@cs.rochester.edu
uucp:  seismo!rochester!ciaraldi