Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!pepper!cmcmanis
From: cmcmanis%pepper@Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga
Subject: Re: Is there a new virus?
Message-ID: <37396@sun.uucp>
Date: 27 Dec 87 00:08:14 GMT
References: <522@io.UUCP> <20491@linus.UUCP>
Sender: news@sun.uucp
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Distribution: na
Organization: Sun Microsystems, Mountain View
Lines: 25

In article <20491@linus.UUCP> sdl@linus.UUCP (Steven D. Litvintchouk) writes:
>Hmmm, I have just encountered *exactly* the same symptoms, immediately
>after having accessed a new batch of Fred Fish disks (# 111 - 118).
>In fact, disk # 111 went completely bad, also around tracks 40-41!
>Fred, if you're out there somewhere, have you noticed any problems
>with these disks?

Actually, trashing tracks 40/41 does not require a virus. There is a 
known bug with the Delay() system call that can cause disk corruption.
Basically, if you call Delay() with and argument of 0, and the disk
is being accessed, there is a finite chance that the disk will get 
zapped. Now, the most well know cause of this was ther Dillon/Drew
shell program (pre version 2.06 I believe). Ok, that aside, the most
common programming practice that gets people in trouble is using 
WaitForChar(0L) to simulate polling the console.device for status.
This is common in programs like titlebar clocks that want to run in 
a loop but check now and then for a key press. The correct way to do 
this is to get VANILLAKEY or RAWKEY events in your window and handle them
in the event loop. Or use WaitForChar(1L). Anyway, what were you running 
at the time? Something to think about. 


--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses, but you knew that didn't you.