Provides maximum efficiency and control over double buffering while still maintaining compatibility with the Sound Manager.

OSErr SndPlayDoubleBuffer (
    SndChannelPtr chan, 
    SndDoubleBufferHeaderPtr theParams
);

Parameter descriptions

chan

A pointer to a valid sound channel.

theParams

A pointer to a sound double buffer header structure.

function result

A result code.

DISCUSSION

The SndPlayDoubleBuffer function launches a low-level sound play using the information in the double buffer header structure specified by theParams. After your application calls this function, the Sound Manager repeatedly calls the doubleback function you specify in the double buffer header structure. The doubleback function then manages the filling of buffers of sound data from disk whenever one of the two buffers specified in the double buffer header structure becomes exhausted.

The Sound Manager’s high-level play-from-disk routines make extensive use of this function.

Because the SndPlayDoubleBuffer function might move memory, you should not call it at interrupt time.

SPECIAL CONSIDERATIONS

You can use the SndPlayDoubleBuffer function only on a Macintosh computer that supports the play-from-disk functions.

AVAILABILITY

Not supported in Carbon. Not available in Carbon.

CARBON NOTES

Use other Sound Manager or QuickTime functions to play sounds.

© 2000 Apple Computer, Inc. (Last Updated 6/30/2000)