Topic created on: May 7, 2010 08:36 CDT by dodamn .

Hello.

I have an EXE file for MS-DOS. It is built by Watcom C/C++ compiler and has DOS/4GW extended format.
I want to reverse-engineer it.

So First, I use IDA pro Hex-ray. But it is my first time for reversing. So I just open the file in IDA pro and just click 'Next', 'Next' and 'Next'. :) But IDA pro is GOD!. It shows assembly code! And I can create .c code using menu 'File'->'Produce file'->'Create C file'. I tried to compile those disassembled/decompiled codes. But it failed.

Second, I use DOSBox. Because DOSBox(debug mode) shows registers' values, assembly code. Also DOSBox provide breakpoint feature. But assembly code what DOSBox shows is not same as IDA pro does. So I can't put breakpoint properly. Why code, what DOSBox shows, is different from what IDA pro shows?

Anyway, what is the best way for reversing DOS/4GW extended EXE file?
Is there any way to put breakpoint on somewhre in the code when the program runs?