Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!att!cbnewsk!ech
From: ech@cbnewsk.att.com (ned.horvath)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Determining whether MultiFinder is present
Message-ID: <1990Oct9.203522.11201@cbnewsk.att.com>
Date: 9 Oct 90 20:35:22 GMT
References: <45479@apple.Apple.COM>
Organization: AT&T Bell Laboratories
Lines: 50

In article <10540.270e461f@amherst.bitnet> mbabramowicz@amherst.bitnet writes:
>Tech Notes seem to say that you can't determine whether or not Multifinder is
>present. But Font/DA Mover seems to know...

From article <45479@apple.Apple.COM>, by das@Apple.COM (David Shayer):
> You probably know the standard answer to this:  You don't need to know.
> Instead, check for the specific feature you need...

And you apparently need the standard rejoinder to this: if Apple programmers
have a legitimate need to know (as Font/DA mover needs to know; as the
LaserWriter needs to know so that it can selectively highlight the
"Background Printing" button; but two ought to suffice), then non-Apple
programmers have that very same need to know.

The simple example is that I need to know if "Launch" will return or not
(the Laserwriter example is a special case of this) so that I know whether
or not I can launch a background task.

I tried using Gestalt to see if it would help me with the "will Launch
return" question.  According to IM VI, Gestalt selector 'os  ' ought to
be just the ticket.  But Gestalt returns error -5551 (selector unknown)
in system 6.0.x.  So much for asking the specific question you need
the answer to.

> If you simply want to know for academic interest, there are several different
> (and very easy) ways to check, but I'll leave that as an exercise for the
> reader.

Grow up: he asked for help, for a "legit" way to test.  If you can
provide same, please do so.  If not, your "I know, but I won't tell" is
merely infuriating.

A couple that SHOULD work (no promises):
- call SysEnvirons.  If the system version is >= $0700, MF is always on.

- Use NGetTrapAddress to see if $A88F (OSDispatch) is the same as $A89F
  (will "always" be unimplemented).  If they don't match, MF is running.

- Among the first dozen or so events you'd receive from WaitNextEvent
  there will be a "Resume" event if MF is running.


Notice that the last two suggestions may fail with 6.0.6 (the system version
for the "new" machines that are being announced 10/15).  In fact, any
suggestion may fail then, depending on how determined Apple are to protect
their monopoly on knowing if MF is running.

This is a silly game.  Can we stop now?

=Ned Horvath=