Date: Wed, 20 May 1998 14:51:10 +0100
From: Matthias Paul <PAUL-MA AT reze-1 DOT rz DOT rwth-aachen DOT de>
Subject: Re: QEMM and DR-DOS
To: opendos AT delorie DOT com
Reply-to: Matthias DOT Paul AT post DOT rwth-aachen DOT de
Message-id: <1AEF874878@reze-1.rz.rwth-aachen.de>
Organization: Rechenzentrum RWTH Aachen
Precedence: bulk

On Wed, 20 May 1998 I wrote:

> Some months ago, I have written an automated patch for this problem,
> and I may post it here in a few days, so that all people who prefer
> using QEMM over using Windows (or have a very late issue of Windows
> 3.1x installed) can take advantage of both.

Well, I had a look through the archives, and here it is:

------

; Copyright (C) 1997,1998 by Matthias Paul. All rights reserved.
; 
; eMail: <Matthias DOT Paul AT post DOT rwth-aachen DOT de> 
;
; This is provided "AS IS". Use at your own risk! 
; No warranty of any kind. No support! 
;
; Never run on other files than IBMBIO.COM of DR-OpenDOS 7.02 or 
; DR-DOS 7.02+. However, it is not garanteed that this patch will 
; continue to work with future issues of DR-DOS, though it s unlikely
; to become broken.  (You can retrieve the version number with 
; "VERSION IBMBIO.COM")!  Never use older versions of DEBUG than 
; DEBUG R1.50+! 
;
; Description: Caldera DR-OpenDOS 7.02+ DEBUG 1.50+ script to patch 
;              the IBMBIO.COM file to allocate only 5 instead of 8 
;              handles during [[O]D]CONFIG.SYS. (NB. ODCONFIG.SYS was 
;              only supported by DR-OpenDOS 7.02.) 
;
; Purpose:     1. This patch fixes a problem with Quarterdeck's 
;                 QEMM DOS-UP, which refuses to relocate DOS sub-
;                 structures, resulting in about 1 Kb less total 
;                 conventional memory.
;              2. The fix also gives about 150 bytes more 
;                 conventional memory on systems, where handles are 
;                 loaded into UMBs using the new FILESHIGH/FCBSHIGH 
;                 directives. 
; Drawback:    1. MS Windows 3.xx probably will not run after 
;                 applying this patch to IBMBIO.COM. Instead, it 
;                 will display: "Unsupported version of MS-DOS" on 
;                 startup. Note, that at least MS WfW 3.11 still runs 
;                 without problems. 
;                 If you have success running a different version of 
;                 MS Windows after applying this patch, I would be 
;                 pleased to get your feedback.
;
; HowTo:       1. Remove the attributes from the IBMBIO.COM file.
;              2. Copy a backup copy of the file onto a bootable 
;                 floppy disk.
;              3. Run DEBUG < ibmbio85.scr in the root directory of 
;                 your boot drive.
;              4. Apply the old attributes to the IBMBIO.COM file.
;
; Version    : 1.02
; Last edit  : 1998-05-20 MPAUL
;
/X                                ; Enter extended DEBUG mode
Nibmbio.com                       ; Name & load the BIOS from disk 
                                  ; (+100h)
L
R ax=cx                           ; Save file length
R cx=0                            ; Search for 1st match and store 
                                  ; loc. in CX
-S cs:100 L ax+100 "IBMDOS",20,20
R dx=cx                           ; Store location in DX (0 if not 
                                  ; found)
R cx=0                            ; Search for 1st match and store 
                                  ; loc. in CX
-S cs:dx-A L 1 4
;-S cs:dx-A L 1 1                 ; [To revert the patch modify above 
                                  ; line!]
                                  ; If CX is zero, the correct 
                                  ; DEF_NUM_FILES value (4) was not 
                                  ; found, hence the patch does not 
                                  ; alter the file (it's directed
                                  ; into dummy PSP at offset +0h).
                                  ; Otherwise DEF_NUM_FILES is 
                                  ; patched from 4 to 1. 
E cs:cx 1
;E cs:cx 4                        ; [To revert the patch modify above 
                                  ; line!]
R cx=ax                           ; Restore file length
                                  ; Write the BIOS back to disk
W
Q                                 ; Quit DEBUG

-------

This might also give a good demonstration of some of the powerful &
advanced features of Caldera s DEBUG.

Hope it helps,

 Matthias
 

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 eMail: <Matthias DOT Paul AT post DOT rwth-aachen DOT de>
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