From:	Elliott Moreton	Date:	Fri Dec 27 10:36:05 2002
Subject:	Re: [MacPerl-Toolbox] Sound Manager and "file reference numbers"

Hi,

Off-list help has partially solved the problem; however, another lurks 
beyond it.  

Inside Macintosh says that in order to have the whole file played, you
should pass SndStartFilePlay a NIL for a parameter called theSelection,
which is of type AudioSelection (Ch. 2, "Using the Sound Manager", p.
2-53).  MacPerl won't accept 0, '', (), [], or {} as a null value for this 
parameter:

	use Mac::Sound;
	
	$sounddir = "Macintosh HD:Moreton:exp14:SW:testsounds";

	$infile = "$sounddir:000.aiff";
	open (IN, $infile) || die "Couldn't open $infile";

	$Chan = SndNewChannel (sampledSynth (), initMono (), 0);
	$kBufferSize = 20000;

	$err = SndStartFilePlay ($Chan, IN, 0, $kBufferSize, '', 0, 0);
                                                             ^
                                                             |
                                                        theSelection

The error I get is 

	# theSelection is not of type AudioSelection

The Sound.pm code section on SndStartFilePlay has the following variable 
declarations:

	SndChannel	chan
	short		fRefNum	 (filehandle seems to work)
	short		resNum	 (0, since this is a file, not a resource)
	long		bufferSize
	AudioSelection	&theSelection
	SV		*theCompletion
	Boolean		async

Can anyone see what the problem is?  I'm sure this is extremely basic, but 
I'm baffled.

Thanks,
Elliott Moreton