Aconnect

Usage

   Usage:
    * Connection/disconnection betwen two ports
      aconnect [-options] sender receiver
        sender, receiver = client:port pair
        -d,--disconnect     disconnect
        -e,--exclusive      exclusive connection
        -r,--real #         convert real-time-stamp on queue
        -t,--tick #         convert tick-time-stamp on queue
    * List connected ports (no subscription action)
      aconnect -i|-o [-options]
        -i,--input          list input (readable) ports
        -o,--output         list output (writable) ports
        -l,--list           list current connections of each port
    * Remove all exported connections
        -x, --removeall

Use 'aconnect -lio to see all i/o ports and connections.

Example (SBlive soundcard)

Here is an example of a SBlive soundcard, the DMIDI distributed daemon, LinuxSampler and two copies of TiMidity running with different configurations plus MusE listening to the timer and a MIDI keyboard and outputting to all 3 SoftSynths as well as the keyboard. The external keyboard on the SBlives MIDI input (in this case, on the front panel of a LiveDrive) was set up with aconnect 64:0 129:0 to be able to play a GigaSampler piano sound font via LinuxSampler. The MusE settings were setup from within the MusE program itself.

   # aconnect -lio
   client 0: 'System' [type=kernel]
       0 'Timer           '
       1 'Announce        '
           Connecting To: 131:0
   client 64: 'Rawmidi 0 - EMU10K1 MPU-401 (UART)' [type=kernel]
       0 'EMU10K1 MPU-401 (UART)'
           Connecting To: 129:0, 131:0
           Connected From: 131:0
   client 65: 'Emu10k1 WaveTable' [type=kernel]
       0 'Emu10k1 Port 0  '
       1 'Emu10k1 Port 1  '
       2 'Emu10k1 Port 2  '
       3 'Emu10k1 Port 3  '
   client 128: 'DMIDI' [type=user]
       0 'DMIDI - Receive: [ff:ff:ff:ff]'
       1 'DMIDI - Transmit [ff:ff:ff:ff]'
   client 129: 'LinuxSampler' [type=user]
       0 'LinuxSampler    '
           Connected From: 64:0, 131:0
   client 130: 'Client-130' [type=user]
       0 'TiMidity port 0 '
           Connected From: 131:0
       1 'TiMidity port 1 '
           Connected From: 131:0
   client 131: 'MusE Sequencer' [type=user]
       0 'MusE Port 0     '
           Connecting To: 130:0, 130:1, 64:0, 129:0
           Connected From: 0:1, 64:0

A simplistic guideline for the client numbers used above is...

0..63: for internal use (0 = system, 63 = OSS sequencer emulation)
64..127: device drivers (up to 8 for each card)
128..?: user applications

(thanks to Clemens Ladisch on the alsa-users mailing-list)

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