Technical Knowledge Base

kernel space
- priv full access
- ring 0
user space
- less priv
- ring 3
- cannot access hardware directly
- interact with hardware by asking kernel
New Device
- attached
- kernel populates driver in /sys
- udev receive device
- reads rules in /etc/udev/rules.d/
- creates device nodes in /dev
- notifies dbus

D-Bus - Desktop BUS
- interprocess comm software bus
- system bus provides access to system services
- system bus created at startup
- session bus created at user login
- comm for apps in same desktop sesh
- standardizes desktop interaction / comm

sudo udevadm monitor
sudo dbus-monitor

dbus is a system the kernel uses to interact with the hardware. This happens at the hardware abstraction layer.