This subclass of SoundRecorder supports real-time processing of incoming sound data. The sound input process queues raw sound buffers, allowing them to be read and processed by the client as they become available. A semaphore is used to synchronize between the record process and the client process. Since sound data is buffered, the client process may lag behind the input process without losing data.

	initialization
	initialize

	private
	allocateBuffer emitBuffer:

	recording controls
	startRecording stopRecording

	accessing	top
	bufferCount Answer the number of sound buffers that have been queued.
	bufferSize
	bufferSize: Set the sound buffer size. Buffers of this size will be queued for the client to process.
	isRecording Answer true if the sound input process is running.
	nextBufferOrNil Answer the next input buffer or nil if no buffer is available.

	initialization	top
	initialize SoundRecorder new

	private	top
	allocateBuffer Allocate a new buffer and reset nextIndex. This message is sent by the sound input process.
	emitBuffer: Queue a buffer for later processing. This message is sent by the sound input process.

	recording controls	top
	startRecording Start the sound input process.
	stopRecording Turn off the sound input process and close the driver.