Provided by: keyd_2.5.0-4_amd64 
NAME
keyd.rvaiya - A key remapping daemon.
SYNOPSIS
keyd.rvaiya [command] [options]
COMMANDS
monitor [-t]
Print key events. If -t is supplied, also prints time since the last event in ms. Useful for
discovering key names/device ids and debugging.
listen
Print layer state changes of the running keyd daemon to stdout. Useful for scripting.
bind reset|<binding> [<binding>...]
Apply the supplied bindings. See Bindings for details.
reload
Reload config files.
list-keys
List valid key names.
input [-t <timeout>] <text> [<text>...]
Input the supplied text. If no arguments are given, read the input from STDIN. A timeout in
microseconds may optionally be supplied corresponding to the time between emitted events.
do [-t <timeout>] [<exp>]
Execute the supplied expression. See MACROS for the format of <exp>. If no arguments are given, the
expression is read from STDIN. If supplied, <timeout> corresponds to the macro_sequence_timeout.
OPTIONS
-v, --version
Print the current version and exit.
-h, --help
Print help and exit.
DESCRIPTION
keyd is a system wide key remapping daemon which supports features like layering, oneshot modifiers, and
macros. In its most basic form it can be used to define a custom key layout that persists across display
server boundaries (e.g wayland/X/tty).
The program runs in the foreground, printing diagnostic information to the standard output streams, and
is intended to be run as a single instance managed by the init system.
NOTE:
Because keyd modifies your primary input device, it is possible to render your machine unusable with a
bad config file. If you find yourself in this situation the panic sequence <backspace>+<escape>+<enter>
will force keyd to terminate.
CONFIGURATION
Configuration files loosely follow an INI style format consisting of headers of the form [section_name]
followed by a set of bindings. Lines beginning with a hash are ignored.
Config files are stored in /etc/keyd/ and loaded upon initialization. The reload command can be used to
update the working set of config files (e.g sudo keyd reload).
A valid config file has the extension .conf and must begin with an [ids] section that has one of the
following forms:
[ids]
<id 1 (obtained via keyd.rvaiya monitor)>
<id 2>
...
or
[ids]
*
-<id 1>
-<id 2>
...
The first form specifies a list of ids to be explicitly matched, while the second matches any id which
has not been explicitly excluded.
For example:
[ids]
*
-0123:4567
Will match all keyboards which do not(2) have the id 0123:4567, while:
[ids]
0123:4567
will exclusively match any devices which do. Device ids can be obtained from the monitor command (see
COMMANDS). Note that a device id may only be listed in a single config file.
Each subsequent section of the file corresponds to a layer (with the exception of [global] (see GLOBALS).
Config errors will appear in the log output and can be accessed in the usual way using your system's
service manager (e.g sudo journalctl -eu keyd).
If an id matches more than one device type, the prefix k: may be used to exclusively match keyboards and
the prefix m: may be used to exclusively match mice. (E.g m:046d:b01d)
Note: All keyboards defined within a given config file will share the same state. This is useful for
linking separate input devices together (e.g foot pedals).
Note 2: The wildcard will only match devices which keyd identifies as keyboards. keyd is also capable of
managing mice (e.g to facilitate clearing of oneshot modifiers on click), but their ids must be
explicitly listed.
Note 3: Mouse support is currently experimental, and is mostly confined to traditional mice (e.g
touchpads). Adding some mice to your ids section may break your pointer. It may also be necessary to
explicitly blacklist mice which are misidentified as keyboards (e.g if you find your moused misbehaving).
Layers
A layer is a collection of bindings, each of which specifies the behaviour of a particular key. Multiple
layers may be active at any given time, forming a stack of occluding keymaps consulted in activation
order. The default layer is called main and is where common bindings should be defined.
For example, the following config snippet defines a layer called nav and creates a toggle for it in the
main layer:
[main]
capslock = layer(nav)
[nav]
h = left
k = up
j = down
l = right
When capslock is held, the nav layer occludes the main layer causing hjkl to function as the
corresponding arrow keys.
Unlike most other remapping tools, keyd provides first class support for modifiers. A layer name may
optionally end with a ':' followed by a set of modifiers to emulate in the absence of an explicit
mapping. Layer names may consist of a maximum of 64 characters (including all modifiers).
These layers play nicely with other modifiers and preserve existing stacking semantics.
For example:
[main]
capslock = layer(capslock)
[capslock:C]
j = down
will cause capslock to behave as control, except in the case of capslock+j, which will emit down. This
makes it trivial to define custom modifiers which don't interfere with one another.
Note that bindings are not affected by the modifiers of the layer in which they are defined. Thus
capslock+j will produce an unmodified down keypress, while shift+capslock+j will produce shift+down as
expected.
Formally, each layer heading has the following form:
"[" <layer name>[:<modifier set>] "]"
Where <modifier_set> has the form:
<modifier1>[-<modifier2>]...
and each modifier is one of:
C - Control
M - Meta/Super
A - Alt
S - Shift
G - AltGr
Finally, each layer heading is followed by a set of bindings which take the form:
<key> | <alias> = <key>|<macro>|<action>
for a description of <action> and <macro> see ACTIONS and MACROS.
By default, each key is bound to itself within the main layer. The exception to this are the modifier
keys, which are instead bound to eponymously named layers with the corresponding modifiers.
For example, meta is actually bound to layer(meta), where meta is internally defined as meta:M.
The full set of modifier bindings are as follows:
control = layer(control)
meta = layer(meta)
shift = layer(shift)
leftalt = layer(alt)
rightalt = layer(altgr)
A consequence of this is that overriding modifier keys is a simple matter of adding the desired bindings
to an appropriate pre-defined layer.
Thus
[ids]
*
[control]
j = down
is a completely valid config, which does what the benighted user might expect. Internally, the full
config actually looks something like this:
[ids]
*
[main]
leftcontrol = layer(control)
rightcontrol = layer(control)
[control:C]
j = down
If multiple bindings for the same key are present, the most recent one takes precedence.
A layer heading may also appear multiple times, in which case the layer will contain the sum of all
bindings. Note that the layer type may not be reassigned.
That is:
[mylayer:A]
a = b
c = d
[mylayer:C]
a = x
b = c
is equivalent to:
[mylayer:A]
a = x
b = c
c = d
Composite Layers
A special kind of layer called a composite layer can be defined by creating a layer with a name
consisting of existing layers delimited by +. The resultant layer will be activated and given precedence
when all of its constituents are activated. Composite layers are not allowed to have modifiers attached
and cannot be explicitly assigned.
E.g.
[control+alt]
h = left
will cause the sequence control+alt+h to produce left (ignoring the control and alt modifiers attached to
the active control and alt layers), while pressing control+alt+f1 preserves those modifiers, emitting
exactly what was pressed, as there is no explicit binding for f1 on the composite layer.
[main]
capslock = layer(capslock)
[capslock:C]
[capslock+shift]
h = left
Will cause the sequence capslock+shift+h to produce left, while preserving the expected functionality of
capslock and shift in isolation.
Note: composite layers must always be defined after the layers of which they are comprised.
That is:
[layer1]
[layer2]
[layer1+layer2]
and not
[layer1+layer2]
[layer1]
[layer2]
Layouts
A layout is a special kind of layer intended for modifying alpha keys. Unlike layers, layouts cannot have
any associated modifiers, and only one layout may be active at a given time. The default layout is called
'main', and can be changed using the setlayout() action.
For convenience, keyd ships with a number of common letter layouts in /usr/share/keyd/layouts. Before
including these, it is instructive to inspect them. Non-english layouts include a dedicated shift layer
(making order of inclusion important) and require the use of keyd's compose definitions (see Unicode
Support)
E.g.
# Include the shipped colemak layout.
include layouts/colemak
[global]
default_layout = mylayout
[mylayout:layout]
a = b
b = c
#etc...
[control]
1 = setlayout(customlayout)
2 = setlayout(colemak)
Chording
Chords are groups of keys which are treated as a unit when simultaneously depressed. A chord can be
defined by using a group of + delimited key names as a left hand value. The corresponding action will be
activated if all keys are struck within the chording interval (chord_timeout).
E.g
j+k = esc
will cause esc to be produced if both j and k are simultaneously depressed.
Note: It may be desirable to change the default chording interval (50ms) to account for the physical
characteristics of your keyboard.
Unicode Support
If keyd encounters a valid UTF8 sequence as a right hand value, it will try and translate that sequence
into a macro which emits a keyd-specific XKB sequence.
In order for this to work, the sequences defined in the compose file shipped with keyd
(/usr/share/keyd/keyd.compose) must be accessible. This can be achieved globally by copying the file to
the appropriate location in /usr/share/X11/locale, or on a per-user basis by symlinking it to
~/.XCompose.
E.g.
ln -s /usr/share/keyd/keyd.compose ~/.XCompose
Additionally you will need to be using the default US layout on your display server. Users of non-english
layouts are advised to set their layout within keyd (see Layouts) to avoid conflicts between the display
server layout and keyd's unicode functionality.
Note: You may have to restart your applications for this to take effect.
Note 2: The generated compose sequences are affected by modifiers in the normal way. If you want shift to
produce a different symbol, you will need to define a custom shift layer (see the included layout files
for an example).
Note 3: GTK4 currently has a bug which causes it to crash in the presence of large XCompose files (like
/usr/share/keyd/keyd.compose).
Aliases
Each key may optionally be assigned an alias. This alias may be used in place of the key as a valid left
hand value. Multiple keys may be bound to the same alias, but only one alias may be assigned to a key at
a given time.
For example, the keys 'leftmeta' and 'rightmeta' are bound to the alias meta by default. Thus the binding
'meta = a' is equivalent to the bindings 'leftmeta = a' and 'rightmeta = a'.
Aliases are defined in a special section called 'aliases' where each line takes the form:
<key> = <name>
where <key> must be a valid key name.
Note that <name> may itself be a valid key name, in which case all references to the key within the
config file will be replaced with the new key. Additionally, if the assigned alias is a valid key name,
the corresponding keycode will be assigned to the key by default. This makes it possible to redefine keys
before any bindings are applied and is particularly useful in conjunction with the include mechanism to
account for variations in hardware.
For example:
/etc/keyd/common:
meta = oneshot(meta)
alt = oneshot(alt)
a = a
s = o
# etc..
/etc/keyd/default.conf:
[ids]
*
[main]
include common
/etc/keyd/magic_keyboard.conf:
[ids]
004c:0267
[aliases]
leftalt = meta
rightalt = meta
rightmeta = alt
leftmeta = alt
[main]
include common
Allows the user to define a set of universal bindings in /etc/keyd/common without having to explicitly
account for the transposed meta and alt keys within the included config snippet.
File Inclusion
Config files may include other files located within the config directory using the include keyword. A
line of the form include <file> may appear at any point after the [ids] section. The resultant config
will behave as though the contents of the included file appear in place of the include statement.
Making strategic use of these statements makes it possible to share common functionality between configs.
Include paths are relative and must be placed in one of the following directories:
• /etc/keyd/
• /usr/share/keyd/
E.g.
/etc/keyd/default.conf:
[ids]
*
# Add our shared custom bindings.
include common
# Appends bindings to the main layer
# defined in /etc/keyd/common (order matters)
[main]
capslock = layer(capslock)
[capslock]
1 = setlayout(colemak)
2 = setlayout(dvorak)
/etc/keyd/common:
[main]
rightmeta = layer(nav)
[nav]
h = left
j = down
k = up
l = right
/usr/share/keyd/layouts/dvorak:
a = a
s = o
...
Limitations:
• All include statements should appear after the [ids] section in the including file.
• Included files should not contain an ids section.
• Included files should not include other files (inclusion is non-recursive).
• Included files should not end in .conf.
GLOBALS
A special section called [global] may be defined in the file and can contain any of the following
options:
macro_timeout: The time (in milliseconds) separating the initial execution of a macro sequence and
the first repetition. (default: 600)
macro_repeat_timeout: The time separating successive executions of a macro. (default: 50)
layer_indicator: If set, this will turn the capslock light on whenever a layer is active. Note: Some
wayland compositors will aggressively toggle LED state rendering this option unusable.
(default: 0)
macro_sequence_timeout: If set, this will add a timeout (in microseconds) between each emitted key in
a macro sequence. This is useful to avoid overflowing the input buffer on some systems.
chord_timeout: The maximum time between successive keys interpreted as part of a chord. (default: 50)
chord_hold_timeout: The length of time a chord must be held before being activated. (default: 0)
oneshot_timeout: If non-zero, timeout a oneshot layer activation after the supplied number of
milliseconds. (default: 0)
disable_modifier_guard: By default, keyd will inject additional control keypresses where necessary in
order to prevent programs from seeing additional modifier taps (E.g alt in firefox). If set, this
option disables that behaviour. (default: 0)
overload_tap_timeout: If non-zero, ignore the tap behaviour of an overloaded key if it is held for
the given number of miliseconds. (default: 0).
Note: Unicode characters and key sequences are treated as macros, and are consequently affected by the
corresponding timeout options.
MACROS
Various keyd actions accept macro expressions.
A macro expression has one of the following forms:
1. macro(<exp>)
2. [<modifier 1>[-<modifier 2>...]-<key>
3. <char>
Where <char> is a valid unicode character and <exp> has the form <token1> [<token2>...] and each token is
one of:
• A valid key code.
• A type 2 macro.
• A contiguous group of unicode characters.
• A group of key codes delimited by + to be depressed as a unit.
• A timeout of the form <time>ms (where <time> < 1024).
The following are all valid macro expressions:
• C-a
• macro(C-a)
• macro(leftcontrol+leftmeta) # simultaneously taps the left meta and left control keys
• A-M-x
• macro(Hello space World)
• macro(h e l l o space w o r ld) (identical to the above)
• macro(C-t 100ms google.com enter)
Splitting into smaller tokens serves as an escaping mechanism: macro(space) inserts a space but macro(s
pace) writes "space". Likewise, macro(3+5) depresses the 3 and 5 keys as a unit while macro(3 + 5) writes
"3+5".
Some prerequisites are needed for non-ASCII characters to work, see Unicode Support.
ACTIONS
A key may optionally be bound to an action which accepts zero or more arguments.
layer(<layer>)
Activate the given layer for the duration of the keypress.
oneshot(<layer>)
If tapped, activate the supplied layer for the duration of the next keypress.
swap(<layer>)
Swap the currently active layer with the supplied one. If the current layer is toggled, it is
deactivated and the supplied layer is toggled instead. Otherwise, the active layer is deactivated and
the supplied layer remains active for the duration of the depression of the activating key.
[control]
x = swap(xlayer)
[xlayer]
s = C-s
b = S-insert
NOTE:
You probably don't need to use this unless you are trying to do something quite involved. Think hard
about whether or not what you are trying to achieve can be done by other means, as it is easy to end
up in states which are impossible to exit.
setlayout(<layout>)
Set the current layout.
clear()
Clear any toggled or oneshot layers.
toggle(<layer>)
Permanently toggle the state of the given layer.
layerm(<layer>, <macro>)
Identical to layer, but executes the supplied macro before the layer change.
oneshotm(<layer>, <macro>)
Identical to oneshot, but executes the supplied macro before the layer change.
swapm(<layer>, <macro>)
Identical to swap, but accepts a macro to be executed immediately after the layer change.
togglem(<layer>, <macro>)
Equivalent to toggle, but additionally executes the supplied macro before toggling the layer.
clearm(<macro>)
Identical to clear, but executes the supplied macro before clearing layers.
Key overloading
overload(<layer>, <action>)
Activates the given layer while held and executes <action> on tap.
overloadt(<layer>, <action>, <timeout>)
Identical to overload, but only activates the layer if the bound key is held for <timeout>
milliseconds. This is mainly useful for overloading keys which are commonly struck in sequence (e.g
letter keys).
Note that this will add a visual delay when typing, since overlapping keys will be queued until the
timeout expires or the bound key is released.
overloadt2(<layer>, <action>, <timeout>)
Identical to overloadt, but additionally resolves as a hold in the event of an intervening key tap.
overloadi(<action 1>, <action 2>, <idle timeout>)
Activate <action 1> if the last non-action (i.e symbol) key was struck less than <timeout>
milliseconds ago, otherwise activate <action 2>.
This can be used in combination with other overload timeouts and is particularly useful for
overloading letter keys (often called 'homerow mods').
For example:
a = overloadi(a, overloadt2(control, a, 200), 150)
will produce a if and only if:
• a is struck within 150ms of another non-action key.
• a is struck more than 150ms after the last non-action key but held for less than 200ms and
there are no intervening key taps.
This reduces the visual latency by immediately resolving the key as a letter when typed midword, but
also facilitates its use as a layer trigger if it is held for a long enough period with no
intervening symbols.
Since this is a common usecase, a macro called lettermod (defined below) has been defined to
facilitate such definitions.
lettermod(<layer>, <key>, <idle timeout>, <hold timeout>)
An alias for:
overloadi(<key>, overloadt2(<layer>, <key>, <hold timeout>), <idle timeout>)
timeout(<action 1>, <timeout>, <action 2>)
If the key is held in isolation for more than <timeout> ms, activate the second action, if the key is
held for less than <timeout> ms or another key is struck before <timeout> ms expires, execute the
first action.
E.g.
timeout(a, 500, layer(control))
Will cause the assigned key to behave as control if it is held for more than 500 ms.
macro2(<timeout>, <repeat timeout>, <macro>)
Creates a macro with the given timeout and repeat timeout. If a timeout value of 0 is used, macro
repeat is disabled.
Note that <macro> must be a valid macro expression.
E.g.
macro2(400, 50, macro(Hello space World))
macro2(120, 80, left)
command(<shell command>)
Execute the given shell command.
E.g.
command(brightness down)
NOTE: Commands are executed by the user running the keyd process (probably root), use this feature
judiciously.
noop
Do nothing.
IPC
To facilitate extensibility, keyd employs a client-server model accessible through the use of -e. The
keymap can thus be conceived of as a living entity that can be modified at run time.
In addition to allowing the user to try new bindings on the fly, this enables the user to fully leverage
keyd's expressive power from other programs without incurring a performance penalty.
For instance, the user may use this functionality to write a script which alters the keymap when they
switch between different tmux sessions.
The application remapping tool (keyd-application-mapper(1)) which ships with keyd is a good example of
this. It is a small python script which performs event detection for the various display servers (e.g
X/sway/gnome, etc) and feeds the desired mappings to the core using -e.
NOTE: Users with access to the keyd socket should be considered privileged (i.e assumed to have access to
the entire system.).
Bindings
The bind command accepts one or more bindings, each of which must have the following form:
[<layer>.]<key> = <key>|<macro>|<action>
Where <layer> is the name of an (existing) layer in which the key is to be bound.
As a special case, the string "reset" may be used in place of a binding, in which case the current keymap
will revert to its original state (all dynamically applied bindings will be dropped).
Examples:
$ keyd bind '- = C-c'
$ keyd bind reset '+ = C-c' # Reset the keyboard before applying the '+' binding (drops the previous '-' binding)
By default expressions apply to the most recently active keyboard.
EXAMPLES
Example 1
Make esc+q toggle the dvorak letter layout.
[ids]
*
[main]
esc = layer(esc)
[dvorak]
a = a
s = o
...
[esc]
q = toggle(dvorak)
Example 2
Invert the behaviour of the shift key without breaking modifier behaviour.
[ids]
*
[main]
1 = !
2 = @
3 = #
4 = $
5 = %
6 = ^
7 = &
8 = *
9 = (
0 = )
[shift]
0 = 0
1 = 1
2 = 2
3 = 3
4 = 4
5 = 5
6 = 6
7 = 7
8 = 8
9 = 9
Example 3
Tapping control once causes it to apply to the next key, tapping it twice activates it until it is
pressed again, and holding it produces expected behaviour.
[main]
control = oneshot(control)
[control]
control = toggle(control)
Example 4
Meta behaves as normal except when ` is pressed, after which the alt_tab layer is activated for the
duration of the leftmeta keypress. Subsequent actuations will thus produce A-tab instead of M-\.
[meta]
` = swap(alt_tab, A-tab)
[alt_tab:A]
tab = A-S-tab
` = A-tab
Example 5
# Uses the compose key functionality of the display server to generate
# international glyphs. # For this to work 'setxkbmap -option
# compose:menu' must # be run after keyd has started.
# A list of sequences can be found in /usr/share/X11/locale/en_US.UTF-8/Compose
# on most systems.
[main]
rightalt = layer(dia)
[dia]
# Map o to ö
o = macro(compose o ")
# Map e to €
e = macro(compose c =)
Example 6
# Tapping both shift keys will activate capslock.
[shift]
leftshift = capslock
rightshift = capslock
Example 7
Capslock will behave as control in all instances except when used in conjunction with 'h/j/k/l' in which
case it will produce arrow keys. If tapped, it will function as escape.
[main]
capslock = overload(capslock, esc)
esc = capslock
[capslock:C]
h = left
k = up
j = down
l = right
Example 8
Disables the esc and end keys.
[main]
esc = noop
end = noop
ENVIRONMENT VARIABLES
KEYD_DEBUG
Debug log level. 0,1,2 can be specified (default: 0).
AUTHOR
Written by Raheman Vaiya (2017-).
BUGS
Please file any bugs or feature requests at the following url:
<https://github.com/rvaiya/keyd/issues>
2025-05-20 keyd.rvaiya(1)