Path: utzoo!mnetor!uunet!yale!cmcl2!acf8!perkins
From: perkins@acf8.UUCP (Mark E. Perkins)
Newsgroups: comp.sys.mac
Subject: Re: MacMan and double-clicking
Message-ID: <1560049@acf8.UUCP>
Date: 18 Apr 88 13:46:00 GMT
References: <23499@bbn.COM>
Organization: New York University
Lines: 37

>>A couple of people have posted saying that after running the MacMan
>>application, double clicking in the Finder no longer opens things (until
>>the machine is rebooted).
>
> It's already been mentioned that this happens because MacMan alters
> the global SysEvtMask at location $0144.  I modified MacMan to prevent this,
> although my method may be incorrect or whatever.  What I did was search for
> the string 0144 using Fedit or any disk editor in the MacMan program and 
> changed it to 0000.  This forces MacMan to store the new event mask in 
> location 0 which is unused.  I would've chosen another place, like AppScratch
  ^^^^^^^^^^^^^^^^^^^^^^^^^^

    This could cause problems on other fronts.  Debuggers like to stick
and odd value in $0000 to assist programmers in trapping null pointer
references (now, who'd be silly enough to do that? 8-)).  Whatever MacMan
was putting into $0144 is now in $0000 and will probably stay there.
If it was odd, then you'd never notice, but if it's even, referencing
a null pointer would have unknown effects.  I wouldn't recommend
this solution.

    I have received several requests for my FKEY that resets $0144.
I had a hard disk catastrophe over the weekend, so I will respond as
soon as everything is recovered.

    Also, Jon Hueras has pointed out to me that the default
System Event Mask is NOT everyEvent, rather it is everyEvent minus
the keyUp bit.  I will make this change before passing along the
FKEY.

	Mark Perkins

Internet:  mark@vml.psych.nyu.edu	(that's VEE-EM-ELL)
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