Glossary#

os_window#

kitty has two kinds of windows. Operating System windows, refered to as OS Window, and kitty windows. An OS Window consists of one or more kitty tabs. Each tab in turn consists of one or more kitty windows organized in a layout.

tab#

A tab refers to a group of kitty windows, organized in a layout. Every OS Window contains one or more tabs.

layout#

A layout is a system of organizing kitty windows in groups inside a tab. The layout automatically maintains the size and position of the windows, think of a layout as a tiling window manager for the terminal. See Arrange windows for details.

window#

kitty has two kinds of windows. Operating System windows, refered to as OS Window, and kitty windows. An OS Window consists of one or more kitty tabs. Each tab in turn consists of one or more kitty windows organized in a layout.

overlay#

An overlay window is a kitty window that is placed on top of an existing kitty window, entirely covering it. Overlays are used throught kitty, for example, to display the the scrollback buffer, to display hints, for unicode input etc.

Terminals can have hyperlinks, just like the internet. In kitty you can control exactly what happens when clicking on a hyperlink, based on the type of link and its URL.

Environment variables#

Variables that influence kitty behavior

KITTY_CONFIG_DIRECTORY#

Controls where kitty looks for kitty.conf and other configuration files. Defaults to ~/.config/kitty. For full details of the config directory lookup mechanism see, kitty --config.

KITTY_CACHE_DIRECTORY#

Controls where kitty stores cache files. Defaults to ~/.cache/kitty or ~/Library/Caches/kitty on macOS.

KITTY_RUNTIME_DIRECTORY#

Controls where kitty stores runtime files like sockets. Defaults to the XDG_RUNTIME_DIR environment variable if that is defined otherwise the run directory inside the kitty cache directory is used.

VISUAL#

The terminal editor (such as vi or nano) kitty uses, when, for instance, opening kitty.conf in response to ctrl+shift+f2.

EDITOR#

Same as VISUAL. Used if VISUAL is not set.

GLFW_IM_MODULE#

Set this to ibus to enable support for IME under X11.

KITTY_WAYLAND_DETECT_MODIFIERS#

When set to a non-empty value, kitty attempts to autodiscover XKB modifiers under Wayland. This is useful if using non-standard modifers like hyper. It is possible for the autodiscovery to fail; the default Wayland XKB mappings are used in this case. See #3943 for details.

Variables that kitty sets when running child programs

LANG#

This is set only on macOS, and only if the country and language from the macOS user settings form a valid locale.

KITTY_WINDOW_ID#

An integer that is the id for the kitty window the program is running in. Can be used with the kitty remote control facility.

KITTY_PID#

An integer that is the process id for the kitty process in which the program is running. Allows programs to tell kitty to reload its config by sending it the SIGUSR1 signal.

WINDOWID#

The id for the OS Window the program is running in. Only available on platforms that have ids for their windows, such as X11 and macOS.

TERM#

The name of the terminal, defaults to xterm-kitty. See term.

TERMINFO#

Path to a directory containing the kitty terminfo database.

KITTY_INSTALLATION_DIR#

Path to the kitty installation directory.

COLORTERM#

Set to the value truecolor to indicate that kitty supports 16 million colors.

KITTY_LISTEN_ON#

Set when the remote control facility is enabled and the a socket is used for control via kitty --listen-on or listen_on. Contains the path to the socket. Avoids needs to use kitty @ --to when issuing remote control commands.

KITTY_PIPE_DATA#

Set to data describing the layout of the screen when running child programs using launch --stdin-source with the contents of the screen/scrollback piped to them.

KITTY_CHILD_CMDLINE#

Set to the command line of the child process running in the kitty window when calling the notification callback program on terminal bell, see command_on_bell.

KITTY_COMMON_OPTS#

Set with the values of some common kitty options when running kittens, so kittens can use them without needing to load kitty.conf.

KITTY_SHELL_INTEGRATION#

Set when enabling Shell integration. It is automatically removed by the shell integration scripts.