Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!decwrl!sun!imagen!geof
From: geof@imagen.UUCP (Geoffrey Cooper)
Newsgroups: comp.sys.apollo
Subject: Re: adb missing ...
Summary: debug command "db"
Message-ID: <1808@imagen.UUCP>
Date: 31 Aug 88 01:08:14 GMT
References: <8808291425.AA04608@richter.mit.edu>
Organization: IMAGEN Corporation, Santa Clara, CA 95052-8101
Lines: 15

In article <8808291425.AA04608@richter.mit.edu>, krowitz@RICHTER.MIT.EDU (David Krowitz) writes:
> I believe I saw a message a while ago about an undocumented switch
> (of course!) to DBX which allowed you to debug the machine code. I

It is the undocumented "db" command in "DEBUG".  I've used it to solve
a few head scratchers (e.g., NULL redefined to -1 at a random position
in a large source file).  Commands include:

	HELP (how I found this out)
	ACCESS (memory/register at given address)
	SS - single step
	WALK - do N single steps.
	QUIT - exit back to debug.

- Geof-- 
UUCP: {decwrl,sun}!imagen!geof ARPA: imagen!geof@decwrl.dec.com