[Tutor] [OFF TOPIC] Re: What is a "symbolic debugger"

[Alan Gauld]

This is miles away from Python but some might find it fun/educational.

"Dick Moores" <rdm at rcblue.com> wrote

>>If you want to have fun with that try loading a simple program into
>>the DOS DEBUG command and stepping through it examining
>>the memory image as you go., It is decidedly non symbolic!
>
> Is that something I should be able to do on Win XP? Would I use 
> debug
> <python filename> at the command line?

You could, but it would be complex since you would be debugging
the python interpreter while it executes your script.

Its probably easier to try it on one of the simpler DOS commands
like edlin.exe (or better still write hello world in C and compile it
and debug that. That way its small enough you should be able
to spot the string in the ASCII part of the memory dump...)

In a DOS prompt CD to C:\WINDOWS\System32
Run

> CD C:\WINDOWS\SYSTEM32
> DEBUG EDLIN.EXE
-

At the '-' prompt type '?' to get a list of commands.
Try the 'd' and 'u' commands for starters.

If you feel really bold (and patient!) you might try stepping through
using 't'. The IP register contains the Instruction Pointer for 
monitoring
progress...

Anything else is a bit risky unless you know what you are doing!

I had to write my first C program using edlin and debug it using 
DEBUG.
It's good for the soul, or so they tell me...

Shortly after I gort a copy of Wordstar and the Microsoft C compiler
with sdb - such luxury... :-)

Alan G.