jack_conosc

Small CLI tool in C for Debian 11 that controls JACK connections over OSC.

Requirements

• JACK (JACK1 or JACK2)
• libjack development package
• liblo development package
• make, gcc

Example (Debian 11):

sudo apt install build-essential libjack-jackd2-dev liblo-dev

Build

make

Run

./jack_conosc

Custom OSC port:

./jack_conosc --port 50420

The tool listens on UDP/OSC port 50420 by default. Responses are always sent to the sender IP on the currently configured UDP port.

Show help:

./jack_conosc --help

OSC Protocol

• Request: /get_clients_all

  • Response per client: /client <jackclientname> <num_inputs> <num_outputs>
  • Final marker: /done get_clients_all

• Request: /get_connections_all

  • Response per connection: /connection <fromname> <fromchannum> <toname> <tochannum>
  • Final marker: /done get_connections_all

• Request: /connection <clientname>

  • Response per outgoing connection of that client: /connection <fromname> <fromchannum> <toname> <tochannum>
  • Final marker: /done connection

• Request: /connection <fromname> <fromchannum> <toname> <tochannum>

  • Creates a connection from output channel to input channel
  • Success: /ok connection <fromname> <fromchannum> <toname> <tochannum>
  • Error: /error <message>

• Request: /disconnect <fromname> <fromchannum> <toname> <tochannum>

  • Removes an existing connection from output channel to input channel
  • Success: /ok disconnect <fromname> <fromchannum> <toname> <tochannum>
  • Error: /error <message>

OSC Usage Examples

Using oscsend (from liblo-tools):

# Query all JACK clients and channel counts
oscsend localhost 50420 /get_clients_all

# Query all active JACK connections
oscsend localhost 50420 /get_connections_all

# Query all outgoing connections for one client
oscsend localhost 50420 /connection s system

# Connect system:out_1 -> myclient:in_1 (by channel index)
oscsend localhost 50420 /connection sisi system 1 myclient 1

# Disconnect system:out_1 -> myclient:in_1
oscsend localhost 50420 /disconnect sisi system 1 myclient 1