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JACK <--> ALSA PCM plugin
=========================

This plugin converts the ALSA API over JACK (Jack Audio Connection
Kit, http://jackit.sf.net) API.  ALSA native applications can work
transparently together with jackd for both playback and capture.

	ALSA apps (playback) -> ALSA-lib -> JACK plugin -> JACK deamon
	ALSA apps (capture) <- ALSA-lib <- JACK plugin <- JACK daemon

This plugin provides the PCM type "jack".  The typical configuration
looks like below:

	pcm.jack {
		type jack
		playback_ports {
			0 alsa_pcm:playback_1
			1 alsa_pcm:playback_2
		}
		capture_ports {
			0 alsa_pcm:capture_1
			1 alsa_pcm:pcapture_2
		}
	}

Put the above to ~/.asoundrc (or /etc/asound.conf), and use "jack" PCM
with your ALSA apps.  For example,

	% aplay -Djack foo.wav

The jack plugin can have two config options: playback_ports and
capture_ports.  Both are compound type config, including the following
format:
	{
		channel	port-name
		channel port-name
		...
	}
The first argument is the channel number (zero-based) and the second
is the corresponding JACK port name.

The plugin is installed in /usr/lib/alsa-lib directory as default,
which is the default search path of additional plugins for alsa-lib.
On a 64bit system like x86-64, the proper prefix option (typically,
--prefix=/usr/lib64) must be given to configure script.