Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!nfsun!eklektik!danbabcock
From: danbabcock@eklektik.UUCP (/dev/ph1)
Newsgroups: comp.sys.amiga.tech
Subject: Two bug reports
Message-ID: <5177@eklektik.UUCP>
Date: 15 Aug 90 03:42:14 GMT
Reply-To: danbabcock@eklektik.UUCP (/dev/ph1)
Organization: Computers, Gerbils, and Games in the Basement, Pgh, PA
Lines: 43

The following are two bug/feature reports that I emailed to Commodore. I'm
posting them because I'm sure some other people are interested, and I'm not
sure if Commodore received my email (no response as of this writing).

I noticed a problem with task exceptions while writing a program that uses
them (a serial.device compatible driver for a super-cheap multiserial,
multiparallel board that works with any Amiga - I use a task exception to handle
non-queued breaks). I hear you groaning already. Yes, I *have* read the
warnings about using task exceptions, but this code only uses Exec - and
Exec supports exceptions internally, right?

Well, I found a case where it (Exec) doesn't. Exceptions fail to work when
the task is (at the time of the exception) in Wait() and the exception
routine itself uses Wait(). The problem is that Wait() writes over
tc_SigWait. The solution is very simple: the exception code should save
tc_SigWait before calling Wait(), and restore it afterwards.

----------------------------------------------------------------------------

I found a bug in the skeleton device driver. The bug appears in both the
printed 1.3 RKM and the latest (to the outside world, at least)
electronicly distributed version (as well as the earlier versions).

The problem is in the flush routine. In the following code (the tail end of
the flush routine)...

   tst.b   d0
   beq.s   1$
   bsr	 InternalStart
1$:
   bra TermIO

...the BEQ should be a BNE. I could explain the "why", but you probably
won't understand (or trust me :-)) until you look at the code for yourself
anyway. I'm surprised that no one reported this one before, although I
assume many people noticed it and fixed it in their own drivers.

-- Dan Babcock
People/Link: DANBABCOCK
Internet: danbabcock@eklektik.pgh.pa.us <-- Note: Invalid on August 17+
Voice: (412)-373-1753 <-- up to and including August 17
New Voice: (814)-862-2931 <-- August 19+
(I'm going off to college...)