public void enableReceiveThreshold( int thresh )
public void enableReceiveThreshold( int thresh ) throws UnsupportedCommOperationException
	public void enableReceiveThreshold( int thresh )	{		if (fd == 0 )			throw new IllegalStateException("No File Descriptor");		if(thresh >=0)		{			threshold=thresh;			NativeEnableReceiveTimeoutThreshold(timeout, threshold,				InputBuffer);		}		else /* invalid thresh */		{			throw new IllegalArgumentException			(				"Unexpected negative threshold value"			);		}	}