i3config

i3config is the configuration file for the i3 tiling window manager, a popular dynamic window manager for the X11 display server. The file is typically located in the user’s home directory under .config/i3/config or, for older installations, ~/.i3/config. It is a plain text file parsed at startup to determine keybindings, window layout rules, and user interface elements.

The configuration format is line‑based and uses a simple syntax. Lines beginning with a comment character (#) are ignored. Each command is written in a single line, often starting with a binding keyword such as bindsym for keybindings, set for variables, or assign for window‑specific rules. Actions are separated by spaces after a command, and braces or semicolons may be used to group multiple statements. Variables are referenced with the syntax $varname.

Typical sections of an i3config file include keybinding definitions (e.g., bindsym $mod+Return exec i3-sensible-terminal), layout rules (e.g., for window title or class, with assign or workspace), modification of i3’s appearance (e.g., set $font, status_command), and user interface tweaks such as status bar configuration. Default configuration files distributed with i3 provide a minimal setup, but a wide range of community‑developed templates exist for customized workflows.

Users often edit i3config manually or via graphical helpers such as i3-config-wizard. After editing, the configuration can be reloaded with the key combination Mod+Shift+r, which signals i3 to re‑parse the config and apply changes without restarting the entire session. This hot‑reloading facilitates rapid experimentation and fine‑tuning of window manager behavior.