You can try DOS32/A this is free realization of DOS4GW if it's works with Icr2, than must be little easier to do something as dos32/a have source code and even debugger

https://github.com/open-watcom/open-watcom-v2 … d/redist/dos4gw
Documentation

https://github.com/open-watcom/open-watcom-v2 … discussions/193
Discussion about getting source

RaVeN-05 wrote on 2025-02-23, 09:22:

You can try DOS32/A this is free realization of DOS4GW if it's works with Icr2, than must be little easier to do something as do […]
Show full quote

You can try DOS32/A this is free realization of DOS4GW if it's works with Icr2, than must be little easier to do something as dos32/a have source code and even debugger

https://github.com/open-watcom/open-watcom-v2 … d/redist/dos4gw
Documentation

https://github.com/open-watcom/open-watcom-v2 … discussions/193
Discussion about getting source

Thanks dude, will try it when I get back to my pc.

Game runs with Dos32-A. Still doesn't accept large heap sizes.

[EDIT] Time to trawl through the source.

Ok, I built Dos32-A from source and my test app can allocate more than 64 MB RAM just fine.

ICR2 seems to run even without a Dos4GW.exe in the folder. I wonder if it's embedded in the game somehow. Placing a Dos4GW (with Dos32A) seems to have no effect, it seems to be using the same version of Dos4GW always.

It doesn't seem to be in the path or anything.

[EDIT] RR.exe appears to run just fine with Dos32A. ICR2 seems to have its own copy.

to force a different dos4gw for an application that already has dos4gw builtin:
you do it this way:
dos4gw.exe app.exe

and here is how to do it permanently
https://www.dosbox.com/wiki/TOOLS:DOS32A

robertmo3 wrote on 2025-02-24, 07:45:

to force a different dos4gw for an application that already has dos4gw builtin:
you do it this way:
dos4gw.exe app.exe

Is there a fix for this?

1V:\CR>dow4gw cart
2Illegal command: dow4gw.
3
4V:\CR>dos4gw cart
5DOS/32A -- Protected Mode Run-time Version 7.35
6Copyright (C) Supernar Systems, Ltd. 1996-2005
7DOS/32A fatal (3006): exec format not supported in file "cart.exe"

[EDIT] I'll try embedding it.

robertmo3 wrote on 2025-02-24, 08:28:

and here is how to do it permanently
https://www.dosbox.com/wiki/TOOLS:DOS32A

It locks up after embedding it. I'll do a disassembly dump to see what's up with it.

[EDIT] They persist even with the unpatched EXE off the CD.

Some minor idea which works for me sometimes.
Compile unmodified dos32a, preserve it.
Compile modified dos32a, preserve it.
Compare both dos32a versions.
Comparison shows how far you should modify assembly code.
And even possible those modifications to apply to dos4gw.
By carrying in hex editor modified bytes or by carrying directly in assembly mode.
Like olly debugger can edit exes assembly directly.

Another try can be a dos4gw to update from last version, maybe Icr2 uses earlier version.

Try unmodified official last build of dos32a with Icr2, does it work?

The game seems to die after being launched[EDIT], being stuck in a keyboard interrupt loop:

Int 21h, function 0x4B is run app.
In a fully functional run Int 21h, function 0x4A is called to resize dos memory right after startup.
[/EDIT]

1file open command 80 file V:\CR.BAT
2Int 10h WriteChar V
3Int 10h WriteChar :
4Int 10h WriteChar \
5Int 10h WriteChar C
6Int 10h WriteChar R
7Int 10h WriteChar >
8Int 10h WriteChar c
9Int 10h WriteChar a
10Int 10h WriteChar r
11Int 10h WriteChar t
12F000:000020C6  int  21                                                
13F000:000014A0  sti                                                    
14F000:000014A1  callback 0025  (DOS Int 21)                            
15file open command 0 file cart.EXE
16F000:000014A6  retf                                                   
17047C:00002EDC  inc  ax                                                
18047C:00002EDD  jb   00000603 ($-28de)          (no jmp)               
19047C:00002EE1  mov  [34B8],esi                 ds:[34B8]=2632F8A1     
20047C:00002EE6  mov  edx,ebx                                           
21047C:00002EE9  call 00002FA0 ($+b4)                                   
22047C:00002FA0  call 00000CF8 ($-22ab)                                 
23047C:00000CF8  push bx                                                
24047C:00000CF9  push ds                                                
25047C:00000CFA  push gs                                                
26047C:00000CFC  pop  ds                                                
27047C:00000CFD  mov  bx,cs:[3470]               cs:[3470]=0000         
28047C:00000D02  mov  ah,3F                                             
29047C:00000D04  int  21                                                
30F000:000014A0  sti                                                    
31F000:000014A1  callback 0025  (DOS Int 21)                            
32F000:00002084  int  16                                                
33F000:000011E0  sti                                                    
34F000:000011E1  callback 000F  (Keyboard)                              

RaVeN-05 wrote on 2025-02-24, 09:21:

Some minor idea which works for me sometimes. Compile unmodified dos32a, preserve it. Compile modified dos32a, preserve it. Comp […]
Show full quote

Some minor idea which works for me sometimes.
Compile unmodified dos32a, preserve it.
Compile modified dos32a, preserve it.
Compare both dos32a versions.
Comparison shows how far you should modify assembly code.
And even possible those modifications to apply to dos4gw.
By carrying in hex editor modified bytes or by carrying directly in assembly mode.
Like olly debugger can edit exes assembly directly.

Another try can be a dos4gw to update from last version, maybe Icr2 uses earlier version.

Try unmodified official last build of dos32a with Icr2, does it work?

This is an umodified Dos32A compiled by me. I'll try the original binary distribution.

[EDIT] I made a mistake when testing it earlier. The original Dos32A version also seems to be able to allocate more than 64 MB of RAM.

The last official build of dos32a when run as dos32a cart.exe also fails with the error I listed previously.

[EDIT] I wonder if the game carries out a checksum verification on dos4gw.exe.

If you compare the disassembly trace, I think the entry point is messed up:

[EDIT] The two file open commands are there because the older dumps patched the game.

1file open command 80 file V:\CR.BAT
2Int 10h WriteChar V
3Int 10h WriteChar :
4Int 10h WriteChar \
5Int 10h WriteChar C
6Int 10h WriteChar R
7Int 10h WriteChar >
8Int 10h WriteChar c
9Int 10h WriteChar a
10Int 10h WriteChar r
11Int 10h WriteChar t
12F000:000020C6  int  21                                                
13F000:000014A0  sti                                                    
14F000:000014A1  callback 0025  (DOS Int 21)                            
15file open command 0 file cart.EXE
16file open command 1 file cart.EXE
17F000:000014A6  retf                                                   
180361:00002382  mov  di,01A4                                           
190361:00002385  mov  ss,di                                             
200361:00002387  add  sp,120E                                           
210361:0000238B  mov  si,0361                                           
220361:0000238E  sub  si,di                                             
230361:00002390  mov  ax,si                                             
240361:00002392  mov  cl,04                                             
250361:00002394  shl  ax,cl                                             
260361:00002396  dec  ax                                                
270361:00002397  mov  ss:[0CE6],ax               ss:[0CE6]=0000         
280361:0000239B  mov  ss:[0CDC],sp               ss:[0CDC]=0000         
290361:000023A0  mov  si,10CC                                           
300361:000023A3  inc  si                                                
310361:000023A4  mov  [0002],si                  ds:[0002]=9FFF         
320361:000023A8  mov  bx,es                                             
330361:000023AA  sub  bx,si                                             
340361:000023AC  neg  bx                                                
350361:000023AE  mov  ah,4A                                             
360361:000023B0  int  21                                                
37F000:000014A0  sti                                                    
38F000:000014A1  callback 0025  (DOS Int 21)                            
39F000:000014A5  iret                                                   
400361:000023B2  mov  ss:[0CEC],ds               ss:[0CEC]=0000         
410361:000023B7  push ss                                                
420361:000023B8  pop  es                                                
430361:000023B9  cld                                                    
440361:000023BA  mov  di,1186                                           
450361:000023BD  mov  cx,1210                                           

Sounds like it may fails because of patches?
Might be, as dos32a can load to different membase, and on fly patches actually modifies wrong things.

RaVeN-05 wrote on 2025-02-24, 09:41:

Sounds like it may fails because of patches?
Might be, as dos32a can load to different membase, and on fly patches actually modifies wrong things.

I've disabled all patching in the failed run.

I think the startup is corrupted, it jumps to the wrong address.

I'll have a look at the source for sb.exe and dos32a.

In the worst scenario
Need to find exactly same version of DOS4GW Icr2 uses, and reverse engineer?
For example IDA Pro is disassembler/decompiler/and great too for reversing. This organize asm code inro formatted blocks, which makes code more readable. It can load 16bit dos apps, realmode with dosbox plug-in, special edition, unfortunately not supports protected mode. As I understand dos4gw runs in real mode and runs app inside of it in protected mode?
Protected dos apps also can be opened in IDA Pro, as LE executable, works great only major limitation is unability to execute it.

RaVeN-05 wrote on 2025-02-24, 10:02:

In the worst scenario Need to find exactly same version of DOS4GW Icr2 uses, and reverse engineer? For example IDA Pro is disass […]
Show full quote

In the worst scenario
Need to find exactly same version of DOS4GW Icr2 uses, and reverse engineer?
For example IDA Pro is disassembler/decompiler/and great too for reversing. This organize asm code inro formatted blocks, which makes code more readable. It can load 16bit dos apps, realmode with dosbox plug-in, special edition, unfortunately not supports protected mode. As I understand dos4gw runs in real mode and runs app inside of it in protected mode?
Protected dos apps also can be opened in IDA Pro, as LE executable, works great only major limitation is unability to execute it.

Is Ida Pro the free DOS version?

RaVeN-05 wrote on 2025-02-24, 10:02:

In the worst scenario Need to find exactly same version of DOS4GW Icr2 uses, and reverse engineer? For example IDA Pro is disass […]
Show full quote

In the worst scenario
Need to find exactly same version of DOS4GW Icr2 uses, and reverse engineer?
For example IDA Pro is disassembler/decompiler/and great too for reversing. This organize asm code inro formatted blocks, which makes code more readable. It can load 16bit dos apps, realmode with dosbox plug-in, special edition, unfortunately not supports protected mode. As I understand dos4gw runs in real mode and runs app inside of it in protected mode?
Protected dos apps also can be opened in IDA Pro, as LE executable, works great only major limitation is unability to execute it.

Trying to run Whiplash with Dos32A bring up the Dosclient window and then:

1V:\WHIP>v:\cr\dos32a rwhip
2DOS/32A -- Protected Mode Run-time Version 7.35
3Copyright (C) Supernar Systems, Ltd. 1996-2005
4.000.000.000.000.000.000.000.000.000.
5ACCELERATED FOR THE RENDITION CHIPSET
6.000.000.000.000.000.000.000.000.000.
7Press a key ...
8Initialising MIDI device A002 ... OK
9Loading Instrument bank file ... OK
10Loading Drums bank file ... OK
11Initialising DIGI device E016 ... OK
12Unable to open texture map data file iplogo.bm
13
14DOS/32A warning (9003): real mode interrupt vector has been modified: INT 00h
15DOS/32A warning (9003): real mode interrupt vector has been modified: INT 24h
16
17V:\WHIP>

[EDIT] Rebel Moon runs with Dos32A, as does Tomb Raider. I'm sure many more of them will run. ICR2 seems to be the odd man out.

run:
Rebel Moon
Descent II
Tomb Raider

don't run:
EuroFighter 2000
CART Racing
NASCAR Racing II
Scorched Planet

not a dos4gw game:
Quake

robertmo3 wrote on 2025-02-24, 10:36:

run: Rebel Moon Descent II Tomb Raider […]
Show full quote

run:
Rebel Moon
Descent II
Tomb Raider

don't run:
EuroFighter 2000
CART Racing
NASCAR Racing II
Scorched Planet

not a dos4gw game:
Quake

I'm guessing the ones that don't run use an embedded dos4gw, apart from quake.

[EDIT] Yup, the ones that don't run have embedded dos4gws, apart from vquake which doesn't use it and whiplash which is just plain incompatible.

In fact cart.exe itself can't be run using its own dos4gw from the command line. It *has* to use the built in version.