Basic configuration

Some basic steps are usually required on Linux systems to make the most out of ossia.

For instance, a lot of Linux capabilities are by default accessible only to the root user, e.g. through sudo for instance. It is generally not feasible to run score as for instance sound daemons such as JACK or PipeWire are per-user ; thus running score under another user would prevent access to sound output.

The way capabilities are granted to non-root users is through the groups system.

We recommend to be in the following groups (and creating them if they aren’t with groupadd "name_of_the_group":

• uucp and / or dialout depending on the distribution for serial port access (including access to DMX devices such as an ENTTEC USB-DMX for instance).
• audio for raw access to sound and MIDI devices (usually this one is by default).
• video for cameras and anything in /dev/video.
• render to be able to use direct rendering through EGLFS, without e.g. X11 or Wayland.
• realtime for enabling low-latency support with e.g. JACK or PipeWire.
• gpio to access GPIO pins, etc.
• i2c to access other raw devices.
• bluetooth to use the Bluetooth support.
• input to use the raw evdev input device and for some BLE devices (Bluetooth gamepads).
• power if you want to be able to control e.g. turning off a computer through score directly.

This can be done in one command:

 $ sudo usermod -a -G dialout,uucp,audio,video,render,realtime,gpio,i2c,bluetooth,input,power $USER

Note that it is necessary to log-out and log-in again after it as this command does not affect the current user session.