Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!batcomputer!cornell!uw-beaver!mit-eddie!bbn.com!nic!news.cs.brandeis.edu!news!phils
From: phils@chaos.cs.brandeis.edu (Phil Shapiro)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Has AppleSoundChip?  Gestalt?  How?
Message-ID: <PHILS.91Apr16142133@chaos.cs.brandeis.edu>
Date: 16 Apr 91 18:21:33 GMT
References: <1991Apr9.011011.29542@kuhub.cc.ukans.edu>
Sender: usenet@news.cs.brandeis.edu
Organization: Symantec Corp.
Lines: 53
In-Reply-To: 2fmlcalls@kuhub.cc.ukans.edu's message of 9 Apr 91 06:10:11 GMT

In article <1991Apr9.011011.29542@kuhub.cc.ukans.edu>
2fmlcalls@kuhub.cc.ukans.edu writes:

   How does one determine if the AppleSoundChip is present?  I got my
   hands on the new Interface files for THINK Pascal (GestaltEqu most
   notably) and tried to blindly call Gestalt('hdwr',theResponse).

From IM VI:
gestaltSoundAttr - Returns information about the sound capabilities of
the machine. (It's 'snd '.)
 
                           CONST  gestaltStereoCapability     = 0;
                                  gestaltStereoMixing         = 1;
                                  gestaltSoundIOMgrPresent    = 3;
                                  gestaltBuiltInSoundInput    = 4;
                                  gestaltHasSoundInputDevice  = 5;
 
If the bit gestaltStereoCapability is TRUE, the available hardware can
play stereo sounds. The bit gestaltStereoMixing indicates that the
sound hardware of the machine mixes both left and right channels of
stereo sound into a single audio signal for the internal speaker. The
gestaltSoundIOMgrPresent bit indicates that the new sound input
routines are available, and the gestaltBuiltInSoundInput bit indicates
that a built-in sound input device is available. The
gestaltHasSoundInputDevice bit indicates that some sound input device
is available.

   LINK_ERROR - Gestalt not implemented {or some such}

If you're going to use the "new" Interfaces, then you must use the
"new" libraries.  If you use the new Interface.lib file, which is on
the System 7 CD-ROM, then you shouldn't get this link error.  If you
don't have the System 7 disk, I can email (or post) a library that
contains the glue for Gestalt.

   So, how does one use Gestalt with THINK Pascal 3.0?  Or how can one
   determine if the ASC is present without a call to Gestalt?  (And,
   related, like calling WNEvent, do you need to check for a TrapAvail
   before even considering a call to Gestalt?)

Yes, you must check to see if Gestalt is avail before using the
Gestalt Manager.  Gestalt's trap is 0xA1AD.

   BTW, I have System 6.07 on an si.  (I would think Gestalt would be
   in 6.07!?)

Gestalt is in all systems after 6.0.4.

	-phil
--
   Phil Shapiro                           Technical Support Analyst
   Language Products Group                     Symantec Corporation
		Internet: phils@chaos.cs.brandeis.edu