Daniel Eklöf


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url-mode: don’t strip the file:// prefix from localhost URIs

Before this patch, the file:// prefix was stripped from URIs,
when the hostname matched the current host (that is, for "local"
URLs).

Unfortunately, the way this was done caused other parts of the URI to
be stripped as well. For example, the 'query' and 'fragment' parts.

This patch simply removes all special casing of file:// URIs.

Since the URL is passed to a generic opener (i.e. we don't have a
special opener application for file:// URIs), the opener helper must
handle the file:// prefix anyway.

Closes #1474

2023-09-21 18:32:57 +02:00


.builds

ci (sr.ht): alpine no longer allows pip installing to the system installation

2023-07-25 16:47:40 +02:00


completions

completions: bash: simplify awk command used to filter terminfo names

2023-01-27 11:47:12 +00:00


doc

doc: keybings default none

2023-09-20 13:20:48 +00:00


icons

Add logo, fixes #27

2020-06-27 21:23:50 +02:00


pgo

pgo: add stub for wayl_fractional_scaling()

2023-07-18 05:48:22 +02:00


scripts

scripts: generate-alt-random: set P2=1 when emitting sixels

2023-06-29 15:40:00 +02:00


subprojects

meson: allow building with wayland-protocols as a subproject

2023-08-08 19:32:45 +02:00


tests

config: remove deprecated option ‘utempter’

2023-07-31 16:47:51 +02:00


themes

add panda theme

2023-08-19 08:03:54 +02:00


utils

xtgettcap: exit immediately when there are no capabilities to query for

2022-10-10 17:17:38 +02:00


.editorconfig

editorconfig: adjust max-line-length, down from 80 to 70

2021-08-07 15:36:19 +02:00


.gitignore

Revert “gitignore: compile_commands.json + .ccls-cache”

2021-06-15 11:29:07 +02:00


.gitmodules

fcft/tllist: remove git submodules

2020-01-11 14:59:39 +01:00


.woodpecker.yml

ci: replace ‘pipeline’ with ‘steps’

2023-08-18 16:46:09 +02:00


CHANGELOG.md

url-mode: don’t strip the file:// prefix from localhost URIs

2023-09-21 18:32:57 +02:00


INSTALL.md

meson: add -Dterminfo-base-name option

2023-07-28 15:40:53 +02:00


LICENSE

license: fix bad copy-paste: first commit was in 2019

2020-07-25 08:50:57 +02:00


README.md

readme: add default shortcut for unicode input

2023-07-10 12:36:41 +02:00


async.c

async: add async_write(), a write primitive to write to a NONBLOCK:ing FD

2019-11-04 13:46:30 +01:00


async.h

async: add async_write(), a write primitive to write to a NONBLOCK:ing FD

2019-11-04 13:46:30 +01:00


base64.c

debug: rename assert() to xassert(), to avoid clashing with

2021-01-16 20:16:00 +00:00


base64.h

base64: implement encode()

2019-07-19 14:19:42 +02:00


box-drawing.c

render: apply new baseline calculation everywhere

2023-07-25 15:53:29 +02:00


box-drawing.h

fcft: adapt to API changes in fcft-3.x

2022-02-05 17:00:54 +01:00


char32.c

char32: only include stdc-predef.h if it is available

2022-03-19 19:52:21 +01:00


char32.h

char32: inline wcs*() wrappers

2022-02-05 17:00:54 +01:00


client-protocol.h

client: add -E,–client-environment

2022-04-12 15:07:40 +02:00


client.c

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


commands.c

osc: add support for OSC 133;A (prompt markers)

2022-06-16 19:02:10 +02:00


commands.h

scrollback: initial support for mouse scrolling

2019-07-10 09:15:37 +02:00


composed.c

composed: insert: require key to be unique

2021-06-24 19:12:25 +02:00


composed.h

fcft: adapt to API changes in fcft-3.x

2022-02-05 17:00:54 +01:00


config.c

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


config.h

config: add tweak.bold-text-in-bright-amount

2023-07-28 15:40:07 +02:00


csi.c

scaling: always round the scaling factor when converting to int

2023-07-25 16:48:50 +02:00


csi.h

performance improvements

2019-07-07 16:32:18 +02:00


cursor-shape.c

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


cursor-shape.h

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


dcs.c

sixel: special case parsing of images with an aspect ratio of 1:1

2023-06-29 15:40:00 +02:00


dcs.h

dcs: initial handling of DCS in general

2020-01-12 11:55:22 +01:00


debug.c

debug: make use of log_msg() in fatal_error() and bug() functions

2021-02-09 12:32:33 +00:00


debug.h

debug: make use of log_msg() in fatal_error() and bug() functions

2021-02-09 12:32:33 +00:00


extract.c

Disable debug logging

2022-04-27 18:44:17 +02:00


extract.h

fcft: adapt to API changes in fcft-3.x

2022-02-05 17:00:54 +01:00


fdm.c

Explicitly initialize sigaction::sa_mask members with sigemptyset(3)

2022-02-12 12:26:42 +00:00


fdm.h

fdm: add support for managing signals

2021-02-12 10:53:10 +01:00


foot-features.h

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


foot-server.service.in

systemd: skip foot-server.service when not in a Wayland context

2023-08-10 11:29:08 +02:00


foot-server.socket

Order the systemd services after graphical-session.target

2023-08-10 11:29:06 +02:00


foot.info

terminfo: add TS capability

2023-06-15 14:31:23 +02:00


foot.ini

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


generate-version.sh

slave: unset TERM_PROGRAM{,_VERSION}

2023-05-18 17:50:48 +02:00


grid.c

sixel: re-scale images when the cell dimensions change

2023-06-30 08:29:35 +02:00


grid.h

osc: add support for OSC 133;A (prompt markers)

2022-06-16 19:02:10 +02:00


hsl.c

config: add tweak.bold-text-in-bright-amount

2023-07-28 15:40:07 +02:00


hsl.h

hsl: add our own implementations of rgb-to-hsl and hsl-to-rgb

2020-11-15 19:45:33 +01:00


ime.c

ime: track IME focus independently from keyboard focus

2022-06-15 19:25:33 +02:00


ime.h

ime: ime_reset_pending_{preedit,commit} is not used outside ime.c

2022-06-15 19:25:32 +02:00


input.c

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


input.h

input: add basic support for touchscreen input

2023-07-05 16:22:28 +02:00


key-binding.c

key-binding: sort binding lists

2023-03-03 18:29:22 +01:00


key-binding.h

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


keymap.h

keymap: change alt+escape to emit EE instead of a CSI 27 sequence

2022-07-28 19:02:05 +02:00


kitty-keymap.h

kitty: F3 is no longer allowed to emit CSI R

2023-04-26 18:34:03 +02:00


log.c

log: don’t default to syslog enabled

2022-12-02 11:45:10 +01:00


log.h

config: add LOG_CONTEXTUAL_{ERR,WARN,ERRNO}

2021-11-13 11:04:28 +01:00


macros.h

osc: use STRLEN() macro to make parse_rgb() more self-documenting

2021-10-20 17:05:36 +01:00


main.c

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


meson.build

meson: allow building with wayland-protocols as a subproject

2023-08-08 19:32:45 +02:00


meson_options.txt

meson: add -Dterminfo-base-name option

2023-07-28 15:40:53 +02:00


misc.c

misc: add timespec_add()

2022-09-23 20:31:08 +02:00


misc.h

misc: add timespec_add()

2022-09-23 20:31:08 +02:00


notify.c

url-mode: add support for XDG activation when opening URLs

2022-05-05 10:02:28 +02:00


notify.h

notify: break out desktop notifications from osc.c

2020-12-10 18:06:24 +01:00


org.codeberg.dnkl.foot-server.desktop

.desktop: remove StartupWMClass from server, use distinct StartupWMClass for foot and footclient

2023-05-22 18:57:54 +02:00


org.codeberg.dnkl.foot.desktop

*.desktop: add StartupWMClass=foot

2023-04-05 14:42:34 +02:00


org.codeberg.dnkl.foot.metainfo.xml

chore: use MIT license for appstream metadata

2022-10-27 13:58:52 +02:00


org.codeberg.dnkl.footclient.desktop

.desktop: remove StartupWMClass from server, use distinct StartupWMClass for foot and footclient

2023-05-22 18:57:54 +02:00


osc.c

osc: update font subpixel mode, and window opaque compositor hint, on alpha changes

2023-05-26 10:01:32 +02:00


osc.h

ocs: renamed parameter size -> required_size in osc_ensure_size()

2019-07-19 09:56:00 +02:00


quirks.c

wayland: refactor: wrap wl_surface pointers in a wayl_surface struct

2023-06-29 15:38:23 +02:00


quirks.h

quirks: sway does not damage surface beneath sub-surface, when unmapped

2023-05-12 14:51:05 +02:00


reaper.c

reaper: monitor SIGCHLD using the FDM instead of via a signalfd

2021-02-12 10:53:10 +01:00


reaper.h

reaper: monitor SIGCHLD using the FDM instead of via a signalfd

2021-02-12 10:53:10 +01:00


render.c

wayland: cursor-shape-v1 is now always available

2023-08-07 16:53:19 +02:00


render.h

refactor: track current xcursor using an enum, instead of a char pointer

2023-07-03 14:36:32 +02:00


search.c

search: regression: refresh current view when canceling a scrollback search

2023-05-15 20:34:58 +02:00


search.h

key-binding: new API, for handling sets of key bindings

2022-04-17 15:39:51 +02:00


selection.c

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


selection.h

selection: selection_on_rows(): use scrollback relative coords

2022-07-28 21:06:57 +02:00


server.c

config: config_free(): pass conf struct by pointer, not by-value

2022-04-12 15:21:43 +02:00


server.h

config: move structs and enums used by config from terminal.h -> config.h

2022-02-09 17:51:04 +01:00


shm-formats.h

shm-formats: #ifdef on formats added in 1.20

2022-06-20 19:20:28 +02:00


shm.c

render: fix application of old scroll damage when double buffering

2022-09-23 20:33:02 +02:00


shm.h

render: fix application of old scroll damage when double buffering

2022-09-23 20:33:02 +02:00


sixel.c

sixel: fix regression for DECGRI with a repeat count of 0

2023-07-11 00:51:32 +08:00


sixel.h

sixel: re-scale images when the cell dimensions change

2023-06-30 08:29:35 +02:00


slave.c

slave: unset TERM_PROGRAM{,_VERSION}

2023-05-18 17:50:48 +02:00


slave.h

config: add a new ‘environment’ section

2022-06-13 11:55:23 +02:00


spawn.c

spawn: set $PWD, in addition to calling chdir(cwd)

2022-10-02 20:11:16 +02:00


spawn.h

url-mode: add support for XDG activation when opening URLs

2022-05-05 10:02:28 +02:00


stride.h

box-drawing: add infrastructure for rendering box drawing characters ourselves

2021-01-01 21:09:31 +01:00


terminal.c

term: improve fallback logic when selecting scaling factor while unmapped

2023-08-18 16:48:18 +02:00


terminal.h

selection: add support for selecting the contents of a quote

2023-09-19 16:23:34 +02:00


tokenize.c

tokenize: free content of argv on failure, and reset the argv pointer

2021-12-25 23:25:30 +01:00


tokenize.h

tokenize: strdup() each individual argv

2021-06-20 14:19:22 +02:00


unicode-mode.c

unicode-mode: ‘q’ aborts Unicode input mode

2022-07-29 11:56:41 +02:00


unicode-mode.h

unicode-input: move input (key press) handling to unicode_mode_input()

2022-07-29 09:26:42 +02:00


uri.c

Tag a couple variables with UNUSED, to fix warnings with clang-15

2023-02-12 19:09:48 +01:00


uri.h

uri: add uri_parse() – new function extracts components from an URI

2020-10-28 19:10:44 +01:00


url-mode.c

url-mode: don’t strip the file:// prefix from localhost URIs

2023-09-21 18:32:57 +02:00


url-mode.h

key-binding: new API, for handling sets of key bindings

2022-04-17 15:39:51 +02:00


user-notification.c

user-notification: config: various small cleanups

2021-11-14 15:16:32 +00:00


user-notification.h

user-notification: config: various small cleanups

2021-11-14 15:16:32 +00:00


util.h

uri: move hex2nibble() to util.h

2022-01-13 13:42:11 +01:00


vt.c

vt: fix ASAN UB warning

2023-08-07 16:38:04 +02:00


vt.h

vt: limit maximum value of params in vt_param_get()

2021-05-17 18:15:34 +01:00


wayland.c

changelog: crash when xdg token is set, but compositor does not support activation

2023-09-21 18:31:46 +02:00


wayland.h

input: improve touch handling on pointer presense

2023-08-24 00:45:20 +08:00


xmalloc.c

fcft: adapt to API changes in fcft-3.x

2022-02-05 17:00:54 +01:00


xmalloc.h

fcft: adapt to API changes in fcft-3.x

2022-02-05 17:00:54 +01:00


xsnprintf.c

Add xsnprintf() and remove some unnecessary strlen(3) calls

2021-01-21 11:57:46 +01:00


xsnprintf.h

Add xsnprintf() and remove some unnecessary strlen(3) calls

2021-01-21 11:57:46 +01:00

The fast, lightweight and minimalistic Wayland terminal emulator.

CI status
Pipeline status
builds.sr.ht status

Packaging status

Index

  1. Features
  2. Installing
  3. Configuration
  4. Troubleshooting
  5. Why the name ‘foot’?
  6. Fonts
  7. Shortcuts
    1. Keyboard
      1. Normal mode
      2. Scrollback search
    2. Mouse
    3. Touchscreen
  8. Server (daemon) mode
  9. URLs
  10. Shell integration
    1. Current working directory
    2. Jumping between prompts
  11. Alt/meta
  12. Backspace
  13. Keypad
  14. DPI and font size
  15. Supported OSCs
  16. Programmatically checking if running in foot
  17. XTGETTCAP
  18. Credits
  19. Bugs
  20. Contact
    1. IRC
    2. Mastodon
  21. Sponsoring/donations
  22. License

Features

  • Fast (see benchmarks, and
    performance)

  • Lightweight, in dependencies, on-disk and in-memory

  • Wayland native

  • DE agnostic

  • Server/daemon mode

  • User configurable font fallback

  • On-the-fly font resize

  • On-the-fly DPI font size adjustment

  • Scrollback search

  • Keyboard driven URL detection

  • Color emoji support

  • IME (via text-input-v3)

  • Multi-seat

  • True Color (24bpp)

  • Synchronized Updates support

  • Sixel image support

    wow

See INSTALL.md.

Configuration

foot can be configured by creating a file
$XDG_CONFIG_HOME/foot/foot.ini (defaulting to
~/.config/foot/foot.ini). A template for that can usually be found
in /etc/xdg/foot/foot.ini or
here.

Further information can be found in foot’s man page foot.ini(5).

Troubleshooting

See the wiki

I’m bad at names. Most of my projects usually start out as foo
something
(for example, yambar
was f00bar for a while).

So why foot?

foo terminalfootermfoot

Pretty bad, I know.

As a side note, if you pronounce the foo part of foot the same way
you pronounce foobar, then foot sounds a lot like the Swedish word
fot, which incidentally means (you guessed it) foot.

Fonts

foot supports all fonts that can be loaded by freetype,
including bitmap fonts and color emoji fonts.

Foot uses fontconfig to locate and configure the font(s) to
use. Since fontconfig’s fallback mechanism is imperfect, especially
for monospace fonts (it doesn’t prefer monospace fonts even though the
requested font is one), foot allows you, the user, to configure the
fallback fonts to use.

This also means you can configure each fallback font individually;
you want that fallback font to use this size, and you want that
other fallback font to be italic? No problem!

If a glyph cannot be found in any of the user configured fallback
fonts, then fontconfig’s list is used.

Shortcuts

These are the default shortcuts. See man foot.ini and the example
foot.ini to see how these can be changed.

Keyboard

Normal mode

shift+page up/page down
Scroll up/down in history
ctrl+shift+c, XF86Copy
Copy selected text to the clipboard
ctrl+shift+v, XF86Paste
Paste from clipboard
shift+insert
Paste from the primary selection
ctrl+shift+r
Start a scrollback search
ctrl++, ctrl+=
Increase font size by 0,5pt
ctrl+-
Decrease font size by 0,5pt
ctrl+0
Reset font size
ctrl+shift+n
Spawn a new terminal. If the shell has been configured to emit the
OSC 7 escape
sequence
,
the new terminal will start in the current working directory.
ctrl+shift+o
Enter URL mode, where all currently visible URLs are tagged with a
jump label with a key sequence that will open the URL.
ctrl+shift+u
Enter Unicode input mode.
ctrl+shift+z
Jump to the previous, currently not visible, prompt. Requires shell
integration
.
ctrl+shift+x
Jump to the next prompt. Requires shell
integration
.
ctrl+r
Search backward for next match
ctrl+s
Search forward for next match
ctrl+w
Extend current selection (and thus the search criteria) to the end
of the word, or the next word if currently at a word separating
character.
ctrl+shift+w
Same as ctrl+w, except that the only word
separating characters are whitespace characters.
ctrl+v, ctrl+shift+v, ctrl+y, XF86Paste
Paste from clipboard into the search buffer.
shift+insert
Paste from primary selection into the search buffer.
escape, ctrl+g
Cancel the search
return
Finish the search and copy the current match to the primary
selection

URL mode

t
Toggle whether the URL is displayed in the jump label or not
escape, ctrl+c, ctrl+g, ctrl+d
Exit URL mode without launching any URLs

Mouse

leftsingle-click
Drag to select; when released, the selected text is copied to the
primary selection. This feature is disabled when client has
enabled mouse tracking.
Holding shift enables selection in mouse tracking enabled
clients.
Holding ctrl will create a block selection.
leftdouble-click
Selects the word (separated by spaces, period, comma, parenthesis
etc) under the pointer. Hold ctrl to select everything
under the pointer up to, and until, the next space characters.
lefttriple-click
Selects the entire row
middle
Paste from primary selection
right
Extend current selection. Clicking immediately extends the
selection, while hold-and-drag allows you to interactively resize
the selection.
wheel
Scroll up/down in history

Touchscreen

tap
Emulates mouse left button click.
drag
Scrolls up/down in history.
Holding for a while before dragging (time delay can be configured)
emulates mouse dragging with left button held.

Server (daemon) mode

When run normally, foot is a single-window application; if you
want another window, start another foot process.

However, foot can also be run in a server mode. In this mode, one
process hosts multiple windows. All Wayland communication, VT parsing
and rendering is done in the server process.

New windows are opened by running footclient, which remains running
until the terminal window is closed, at which point it exits with the
exit value of the client process (typically the shell).

The point of this mode is a) reduced memory footprint – all
terminal windows will share fonts and glyph cache, and b) reduced
startup time – loading fonts and populating the glyph cache takes
time, but in server mode it only happens once.

The downside is a performance penalty; all windows’ input and output
are multiplexed in the same thread (but each window will have its own
set of rendering threads). This means that if one window is very busy
with, for example, producing output, then other windows will suffer.

And of course, should the server process crash, all windows will
be gone.

Typical usage would be to start the server process (foot --server)
when starting your Wayland compositor (i.e. logging in to your
desktop), and then run footclient instead of foot whenever you
want to launch a new terminal.

Foot support socket activation, which means foot --server will only be
started the first time you’ll run footclient. (systemd user units are
included, but it can work with other supervision suites).

URLs

Foot supports URL detection. But, unlike many other terminal
emulators, where URLs are highlighted when they are hovered and opened
by clicking on them, foot uses a keyboard driven approach.

Pressing ctrl+shift+o enters “URL
mode”
, where all currently visible URLs are underlined, and is
associated with a “jump-label”. The jump-label indicates the key
sequence
(e.g. ”AF”) to use to activate the URL.

The key binding can, of course, be customized, like all other key
bindings in foot. See show-urls-launch and show-urls-copy in the
foot.ini man page.

show-urls-launch by default opens the URL with xdg-open. This can
be changed with the url-launch option.

show-urls-copy is an alternative to show-urls-launch, that changes
what activating a URL does; instead of opening it, it copies it to
the clipboard. It is unbound by default.

Jump label colors, the URL underline color, and the letters used in
the jump label key sequences can be configured.

Shell integration

Current working directory

New foot terminal instances (bound to
ctrl+shift+n by default) will open in
the current working directory, if the shell in the “parent”
terminal reports directory changes.

This is done with the OSC-7 escape sequence. Most shells can be
scripted to do this, if they do not support it natively. See the
wiki
for details.

Jumping between prompts

Foot can move the current viewport to focus prompts of already
executed commands (bound to
ctrl+shift+z/x by
default).

For this to work, the shell needs to emit an OSC-133;A
(E]133;AE\) sequence before each prompt.

In zsh, one way to do this is to add a precmd hook:

precmd() {
    print -Pn "e]133;Ae\"
}

See the
wiki
for details, and examples for other shells.

Alt/meta

By default, foot prefixes Meta characters with ESC. This corresponds
to XTerm’s metaSendsEscape option set to true.

This can be disabled programmatically with E[?1036l (and enabled
again with E[?1036h).

When disabled, foot will instead set the 8:th bit of meta character
and then UTF-8 encode it. This corresponds to XTerm’s eightBitMeta
option set to true.

This can also be disabled programmatically with rmm (reset meta
mode
, E[?1034l), and enabled again with smm (set meta mode,
E[?1034h).

Backspace

Foot transmits DEL (^?) on backspace. This corresponds to
XTerm’s backarrowKey option set to false, and to DECBKM being
reset.

To instead transmit BS (^H), press
ctrl+backspace.

Note that foot does not implement DECBKM, and that the behavior
described above cannot be changed.

Finally, pressing alt will prefix the transmitted byte with
ESC.

Keypad

By default, Num Lock overrides the run-time configuration
keypad mode; when active, the keypad is always considered to be in
numerical mode. This corresponds to XTerm’s numLock option set to
true.

In this mode, the keypad keys always sends either numbers (Num
Lock
is active) or cursor movement keys (Up,
Down, Left, Right, Page
Up
, Page Down etc).

This can be disabled programmatically with E[?1035l (and enabled
again with E[?1035h).

When disabled, the keypad sends custom escape sequences instead of
numbers, when in application mode.

DPI and font size

Font sizes are apparently a complex thing. Many applications use a
fixed DPI of 96. They may also multiply it with the monitor’s scale
factor.

This results in fonts with different physical sizes (i.e. if
measured by a ruler) when rendered on screens with different DPI
values. Even if the configured font size is the same.

This is not how it is meant to be. Fonts are measured in point sizes
for a reason; a given point size should have the same height on
all mediums, be it printers or monitors, regardless of their DPI.

That said, on Wayland, Hi-DPI monitors are typically handled by
configuring a “scaling factor” in the compositor. This is usually
expressed as either a rational value (e.g. 1.5), or as a percentage
(e.g. 150%), by which all fonts and window sizes are supposed to be
multiplied.

For this reason, and because of the new fractional scaling protocol
(see below for details), and because this is how Wayland applications
are expected to behave, foot >= 1.15 will default to scaling fonts
using the compositors scaling factor, and not the monitor
DPI.

This means the (assuming the monitors are at the same viewing
distance) the font size will appear to change when you move the foot
window across different monitors, unless you have configured the
monitors scaling factors correctly in the compositor.

This can be changed by setting the dpi-aware option to yes in
foot.ini. When enabled, fonts will not be sized using the
scaling factor, but will instead be sized using the monitors
DPI. When the foot window is moved across monitors, the font size is
updated for the current monitors DPI.

This means that, assuming the monitors are at the same viewing
distance
, the font size will appear to be the same, at all times.

Note: if you configure pixelsize, rather than size, then DPI
changes will not change the font size. Pixels are always pixels.

Fractional scaling on Wayland

For a long time, there was no true support for fractional
scaling
. That is, values like 1.5 (150%), 1.8 (180%) etc, only
integer values, like 2 (200%).

Compositors that did support fractional scaling did so using a hack;
all applications were told to scale to 200%, and then the compositor
would down-scale the rendered image to e.g. 150%. This works OK for
everything except fonts, which ended up blurry.

With wayland-protocols 1.32, a new protocol was introduced, that
allows compositors to tell applications the actual scaling
factor. Applications can then scale the image using a viewport
object, instead of setting a scale factor on the raw pixel buffer.

Supported OSCs

OSC, Operating System Command, are escape sequences that interacts
with the terminal emulator itself. Foot implements the following OSCs:

  • OSC 0 – change window icon + title (but only title is actually
    supported)
  • OSC 2 – change window title
  • OSC 4 – change color palette
  • OSC 7 – report CWD (see shell integration)
  • OSC 8 – hyperlink
  • OSC 9 – desktop notification
  • OSC 10 – change (default) foreground color
  • OSC 11 – change (default) background color
  • OSC 12 – change cursor color
  • OSC 17 – change highlight (selection) background color
  • OSC 19 – change highlight (selection) foreground color
  • OSC 22 – set the xcursor (mouse) pointer
  • OSC 52 – copy/paste clipboard data
  • OSC 104 – reset color palette
  • OSC 110 – reset default foreground color
  • OSC 111 – reset default background color
  • OSC 112 – reset cursor color
  • OSC 117 – reset highlight background color
  • OSC 119 – reset highlight foreground color
  • OSC 133shell integration
  • OSC 555 – flash screen (foot specific)
  • OSC 777 – desktop notification (only the ;notify sub-command of
    OSC 777 is supported.)

See the foot-ctlseq(7) man page for a complete list of supported
control sequences.

Foot does not set any environment variables that can be used to
identify foot (reading TERM is not reliable since the user may have
chosen to use a different terminfo).

You can instead use the escape sequences to read the Secondary and
Tertiary Device Attributes (secondary/tertiary DA, for short).

The tertiary DA response is always EP!|464f4f54E\, where
464f4f54 is FOOT in hex.

The secondary DA response is E[>1;XXYYZZ;0c, where XXYYZZ is
foot’s major, minor and patch version numbers, in decimal, using two
digits for each number. For example, foot-1.4.2 would respond with
E[>1;010402;0c.

Note: not all terminal emulators implement tertiary DA. Most
implement secondary DA, but not all. All should however implement
Primary DA.

Thus, a safe way to query the terminal is to request the tertiary,
secondary and primary DA all at once, in that order. All terminals
should ignore escape sequences they do not recognize. You will have to
parse the response (which in foot will consist of all three DA
responses, all at once) to determine which requests the terminal
emulator actually responded to.

Starting with version 1.7.0, foot also implements XTVERSION, to
which it will reply with EP>|foot(version)E\. Version is
e.g. “1.8.2” for a regular release, or “1.8.2-36-g7db8e06f” for a git
build.

XTGETTCAP is an escape sequence initially introduced by XTerm, and
also implemented (and extended, to some degree) by Kitty.

It allows querying the terminal for terminfo
capabilities. Applications using this feature do not need to use the
classic, file-based, terminfo definition. For example, if all
applications used this feature, you would no longer have to install
foots terminfo on remote hosts you SSH into.

XTerms implementation (as of XTerm-370) only supports querying key
(as in keyboard keys) capabilities, and three custom capabilities:

  • TN – terminal name
  • Co – number of colors (alias for the colors capability)
  • RGB – number of bits per color channel (different semantics from
    the RGB capability in file-based terminfo definitions!).

Kitty has extended this, and also supports querying all integer and
string capabilities.

Foot supports this, and extends it even further, to also include
boolean capabilities. This means foots entire terminfo can be queried
via XTGETTCAP.

Note that both Kitty and foot handles responses to
multi-capability queries slightly differently, compared to XTerm.

XTerm will send a single DCS reply, with ;-separated
capability/value pairs. There are a couple of issues with this:

  • The success/fail flag in the beginning of the response is always 1
    (success), unless the very first queried capability is invalid.
  • XTerm will not respond at all to an invalid capability, unless
    its the first one in the XTGETTCAP query.
  • XTerm will end the response at the first invalid capability.

In other words, if you send a large multi-capability query, you will
only get responses up to, but not including, the first invalid
capability. All subsequent capabilities will be dropped.

Kitty and foot on the other hand, send one DCS response for each
capability in the multi query. This allows us to send a proper
success/fail flag for each queried capability. Responses for all
queried capabilities are always sent. No queries are ever dropped.

  • Ordoviz, for designing and
    contributing foot’s logo.

Please report bugs to https://codeberg.org/dnkl/foot/issues

Before you open a new issue, please search existing bug reports, both
open and closed ones. Chances are someone else has already
reported the same issue.

The report should contain the following:

  • Foot version (foot --version).
  • Log output from foot (run foot -d info from another terminal).
  • Which Wayland compositor (and version) you are running.
  • If reporting a crash, please try to provide a bt full backtrace
    with symbols.
  • Steps to reproduce. The more details the better.

IRC

Ask questions, hang out, sing praise or just say hi in the #foot
channel on irc.libera.chat. Logs are available
at https://libera.irclog.whitequark.org/foot.

Mastodon

Every now and then I post foot related updates on
@dnkl@linuxrocks.online

Foot is released under the MIT license.

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