Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!husc6!harvard!panda!genrad!decvax!wanginst!wang!ephraim
From: ephraim@wang.UUCP (pri=8 Ephraim Vishniac x76659 ms1459)
Newsgroups: net.micro.mac
Subject: Re: _Debugger trap failure
Message-ID: <846@wang.UUCP>
Date: Mon, 28-Jul-86 08:44:09 EDT
Article-I.D.: wang.846
Posted: Mon Jul 28 08:44:09 1986
Date-Received: Wed, 30-Jul-86 00:57:03 EDT
References: <5401@ut-sally.UUCP>
Organization: Wang Labs, Lowell MA
Lines: 17

>      I was just reading the MacsBug version 5.1 documentation that came
> in Supplement Volume I, Issue 3 (the March/June 1986 supplement).  I noticed
> on one of the pages that they don't want anyone using Line-1111 traps anymore
> to break into a debugger....
>      Fine, I thought.  I am always ready to follow the Apple Guidelines.  I'll
> just change this "dc.w $ff00" statement to the approved "_Debugger" trap.
> Assemble; link.  Run.
>      Boom.  A bomb box (with a debugger installed!) ID=12.  The old dsCoreErr.
> Unimplemented trap.  My debugger was virtually helpless.  Reboot.
> 
>      You see, Apple doesn't really have an $a9ff (_debugger) trap.  They fake
> it in the debugger.  I think it only works with the new 5.* series MacsBugs.

I've been using _Debugger for about 1.5 years, since I started using MDS
version 0.5.  I have never had the problem described here.  The Mac always
obediently drops into Macsbug (even pre-historic versions) with an indication
"USERBRK" in that cute, brain-damaged font it uses.