Dvorak <> Qwerty - Keyboard remapping for Linux when pressing L-CTRL, R-CTRL, L-ALT, L-WIN, CAPSLOCK

Since I type with the "Dvorak" keyboard layout, the shortcuts such as ctrl-c, ctrl-x, or ctrl-v are not comfortable anymore for using the left hand only.

Furthermore, many applications have their default shortcuts, which I'm used to. So for these shortcuts I prefer "Qwerty". Since there is no way to configure this, this program intercepts these keys and remaps them from "Dvorak" to "Qwerty" when pressing L-CTRL, R-CTRL, L-ALT, L-WIN, CAPSLOCK, or any of those combinations. CAPSLOCK is also used as a modifier, but can be disabled with the "-c" flag.

With X11 I was relying on the xdq from Kenton Varda. However, this does not work reliably with Wayland.

X11's XGrabKey() works partially with some application but not with others (e.g., gedit is not working). Since XGrabKey() is an X11 function with some support in Wayland, I was looking for a more stable solution. After a quick look to this repo, I saw that Kenton added a systemtap script to implement the mapping. It scared me a bit to follow the systemtap path, so I implemented an other solution based on /dev/uinput. The idea is to read /dev/input, grab keys with EVIOCGRAB, create a virtual device that can emit the keys and pass the keys from /dev/input to /dev/uinput. If L-CTRL, R-CTRL, L-ALT, L-WIN, CAPSLOCK is pressed it will map the keys back to "Qwerty".

This program is tested with Arch and Ubuntu, and Kenton Varda reported that it also works with Chrome OS.

Because dvorak works at the /dev/input level — grabbing raw events with EVIOCGRAB and re-emitting them through a virtual /dev/uinput device — it operates completely independently of the desktop environment's keyboard layout settings. This means:

• Switching layouts scrambles shortcuts. If you switch the OS keyboard layout from Dvorak to Qwerty (e.g., for a different language, a different user, or a non-Dvorak keyboard), dvorak keeps remapping modifier combinations. The result is double-remapped shortcuts: pressing Ctrl+C no longer produces Ctrl+C in either layout — it produces something unexpected like Ctrl+I.

• Multiple keyboards, one mapping. If you have multiple keyboards attached (e.g., a laptop built-in keyboard and an external USB keyboard), each running its own dvorak daemon, switching the OS layout for one keyboard affects the other, but the daemons have no way to know.

• No feedback from the desktop. Since dvorak sits below the display server, it cannot observe layout changes made via GNOME Settings, setxkbmap, swaymsg input, or any other desktop-level tool.

The dvorak program now supports two Unix signals to externally control whether remapping is active:

This allows an external script, desktop shortcut, or layout-switching hook to tell all running dvorak daemons to disable remapping when the OS layout is not Dvorak, and re-enable it when switching back.

Thread safety: if a signal arrives while a modifier-based shortcut is in progress (e.g., the user is holding Ctrl+C), the mode change is deferred until all modifier and remapped keys are released. This prevents key events from being split across two different mapping states, which would result in stuck or phantom keys.

Signal authority: once a signal has set the mode, the Left-Alt triple-press toggle is suppressed. Only another signal can change the mode. This prevents accidental toggling via the keyboard when the mode is being managed externally.

.
├── 80-dvorak.rules              # udev rule — triggers dvorak on device attach
├── dvorak                       # compiled binary
├── dvorak.c                     # source code
├── dvorak@.service              # systemd template service (basic udev-triggered mode)
├── examples/
│   ├── dvorak-signal-sudoers    # sudoers rule for passwordless signaling
│   ├── dvorak-signal.sh         # send on/off signals to all dvorak daemons
│   ├── dvorak-start.sh          # daemon launcher with retry, cleanup, and PID files
│   ├── dvorak-usb.service       # systemd template service for dvorak-start.sh
│   ├── sway_layout_switch_example.sh  # example Sway layout switcher with signal integration
│   └── sway_layout-watcher.sh   # watches Sway input events and signals on layout change
├── LICENSE
├── Makefile
└── README.md

This is the simplest setup. It automatically starts dvorak whenever a keyboard is attached.

make
sudo make install

This will copy 3 files: dvorak, 80-dvorak.rules, and dvorak@.service.

The udev rule matches every input device (SUBSYSTEM=="input", KERNEL=="event[0-9]*") and starts one dvorak@<eventN>.service instance per device — it contains no device filter of its own. Filtering happens inside dvorak, which exits 0 without grabbing anything when the device:

• has no X/C/V keys, i.e. is not a keyboard (mice, power buttons, audio jacks — the common case),
• is dvorak's own Virtual Dvorak Keyboard output device, which is always refused so the mapping cannot be applied twice,
• matches a -i keyword, or fails to match a -m keyword, if either option is given.

So the default installation captures all keyboards. To restrict it to specific ones, or to skip virtual devices created by other remappers, add -m / -i to ExecStart in /etc/systemd/system/dvorak@.service — not to the udev rule:

ExecStart=/usr/local/bin/dvorak -d /dev/input/%i -m "keyb k360 k750"

The signal interface itself still works here — sudo pkill -SIGUSR2 -x dvorak switches every daemon to passthrough. What this setup does not install is dvorak-signal.sh, the sudoers rule that lets a non-root user send those signals, or PID files. Add -p /run/dvorak-%i.pid to ExecStart for PID files, or use Option B for the complete arrangement.

If you switch between keyboard layouts at the OS level (e.g., Dvorak, Qwerty, Ukrainian, Russian), use this setup. It adds PID file tracking, signal-based on/off control, and a sudoers rule so your user can signal the root-owned daemons without a password.

Your user must be in the input group (for the sudoers rule and /dev/input access):

sudo usermod -aG input $USER

Log out and back in for the group change to take effect. Verify with:

groups | grep input

make
sudo cp dvorak /usr/local/bin/dvorak
sudo chmod 755 /usr/local/bin/dvorak

sudo cp examples/dvorak-start.sh /usr/local/bin/dvorak-start.sh
sudo chmod 755 /usr/local/bin/dvorak-start.sh

dvorak-start.sh takes a keyboard name as an argument and:

• Searches /sys/class/input/*/device/name for devices whose name contains the given string. Unlike dvorak's -m, this match is case-sensitive (grep -F), so the name must be spelled as it appears in /proc/bus/input/devices
• Retries for up to 180 seconds (90 attempts, 2 seconds apart) — useful for USB devices that appear after boot
• Kills any stale dvorak process already holding the device
• Starts dvorak with a PID file at /run/dvorak-<eventN>.pid
• Tries each matching event node in turn: exit code 0 means "not a keyboard" (a keyboard usually exposes several event nodes, only one of which carries the keys), so the script moves on to the next candidate. Any other exit code means the real keyboard was found, and the script exits so systemd can restart it

sudo cp examples/dvorak-signal.sh /usr/local/bin/dvorak-signal.sh
sudo chmod 755 /usr/local/bin/dvorak-signal.sh

dvorak-signal.sh reads PID files from /run/dvorak-*.pid, verifies each process is actually a dvorak daemon, and sends the appropriate signal. It auto-elevates to root via sudo -n (non-interactive) when run as a regular user. Falls back to pkill if no valid PID files are found.

The dvorak daemons run as root (started via systemd), so signaling them requires root. The sudoers rule allows members of the input group to run dvorak-signal.sh on and dvorak-signal.sh off as root without a password:

sudo cp examples/dvorak-signal-sudoers /etc/sudoers.d/dvorak-signal
sudo chmod 440 /etc/sudoers.d/dvorak-signal
sudo visudo -cf /etc/sudoers.d/dvorak-signal   # verify syntax — must print "parsed OK"

Security note: the sudoers rule points to /usr/local/bin/dvorak-signal.sh, which is root-owned. Never point a sudoers rule to a user-writable path (e.g., ~/.config/...) as that would allow arbitrary code execution as root.

Copy the template service and reload systemd:

sudo cp examples/dvorak-usb.service /etc/systemd/system/dvorak-usb@.service
sudo systemctl daemon-reload

Enable and start one instance per keyboard, using the keyboard name as the instance identifier:

sudo systemctl enable --now "dvorak-usb@Logitech K750.service"
sudo systemctl enable --now "dvorak-usb@Das Keyboard.service"

Check the status:

systemctl status "dvorak-usb@Logitech K750.service"
journalctl -u "dvorak-usb@Logitech K750.service" -f

# From a terminal — should auto-elevate via sudo and succeed:
dvorak-signal.sh off    # all daemons -> passthrough
dvorak-signal.sh on     # all daemons -> Dvorak remapping enabled

An example Sway layout switching script is provided at examples/sway_layout_switch_example.sh. It switches the Sway keyboard layout and automatically signals all dvorak daemons:

• Switching to Dvorak (index 0) sends dvorak-signal.sh on
• Switching to any other layout sends dvorak-signal.sh off

To use it with Sway, copy it to your scripts directory and bind it to a key:

cp examples/sway_layout_switch_example.sh ~/.config/sway/scripts/layout_switch.sh
chmod +x ~/.config/sway/scripts/layout_switch.sh

Add to your Sway config (~/.config/sway/config):

# Cycle layouts with Super+Space
bindsym $mod+space exec ~/.config/sway/scripts/layout_switch.sh

# Or switch to a specific layout
bindsym $mod+F1 exec ~/.config/sway/scripts/layout_switch.sh dvorak
bindsym $mod+F2 exec ~/.config/sway/scripts/layout_switch.sh us
bindsym $mod+F3 exec ~/.config/sway/scripts/layout_switch.sh ua
bindsym $mod+F4 exec ~/.config/sway/scripts/layout_switch.sh ru

Adapt the layout names and indices in the script to match your Sway input configuration.

Most likely, you will need to use sudo as it needs access to input devices. The following parameters can be used:

usage: dvorak [OPTION]
  -d /dev/input/by-id/...   Specifies which device should be captured.
  -m STRING                 Match only the STRING with the USB device name.
                            STRING can contain multiple words, separated by space.
  -i STRING                 Ignore devices whose name matches STRING.
                            STRING can contain multiple words, separated by space.
                            Takes precedence over -m.
  -t                        Disable layout toggle feature (press Left-Alt 3 times to switch layout).
  -c                        Disable caps lock as a modifier.
  -p FILE                   Write PID to FILE (useful for daemon mode).

Signals:
  SIGUSR1                   Enable Dvorak mapping (on).
  SIGUSR2                   Disable mapping / passthrough (off).

example: dvorak -d /dev/input/by-id/usb-Logitech_USB_Receiver-if02-event-kbd -m "k750 k350"
example: dvorak -d /dev/input/event1 -i "virtual clickmate"

Once installed via make install or systemd services, the mapping will be applied whenever a keyboard is attached.

If you have more mappings, e.g., a Dvorak mapping and a non-Dvorak mapping, you can disable the mapping so the shortcuts are not remapped. There are two ways:

1. Signal-based (recommended): use dvorak-signal.sh off to switch all daemons to passthrough, and dvorak-signal.sh on to re-enable. Once controlled by signals, the keyboard toggle is suppressed — only another signal can change the mode.
2. Keyboard toggle: press 3 times L-ALT to toggle the Dvorak-to-Qwerty remapping on or off. This only works when the mode has not been set by a signal. Can be disabled with the -t flag.

If you see this in journalctl:

Error: Device [Logitech K360] does not match any specified keywords.

it means a -m was given but the device name does not contain any of its keywords, so the device was left alone (exit code 1). Add the relevant keyword to the -m parameter in your service file:

ExecStart=/usr/local/bin/dvorak -d /dev/input/%i -m "keyb k360"

The complement of -m is -i: instead of listing every keyboard to capture, list the device names to skip. This is useful with the udev rule, which starts an instance for every input device that appears — including the virtual devices created by other remappers. Grabbing such a device applies the Dvorak mapping a second time, so a key that should arrive as d arrives as e:

ExecStart=/usr/local/bin/dvorak -d /dev/input/%i -i virtual

A device matching both -i and -m is ignored. Ignoring is not an error: dvorak logs one line (dvorak: ignoring [Clickmate Virtual Device 0] (matched "virtual")) and exits with status 0, without ever grabbing the device.

Or if using the dvorak-start.sh approach, pass the full device name:

ExecStart=/usr/local/bin/dvorak-start.sh "Logitech K360"

Because udev starts an instance for every input device, most instances are expected to exit immediately. The exit code says why, and wrapper scripts rely on it:

All diagnostics are written to stderr, so they appear in journalctl -u 'dvorak@*' even though dvorak@.service sets StandardOutput=null.

The dvorak daemons run as root (started via systemd). If you see Operation not permitted when running dvorak-signal.sh, check:

1. Is the sudoers rule installed?

   sudo cat /etc/sudoers.d/dvorak-signal

2. Is your user in the input group?

   groups | grep input

   If not: sudo usermod -aG input $USER then log out and back in.
3. Is the sudoers file valid?

   sudo visudo -cf /etc/sudoers.d/dvorak-signal

Most likely your user was just added to the input group but hasn't logged out and back in yet. Group changes only take effect on new login sessions.

If dvorak-signal.sh reports stale PID files, it means a previous dvorak process was killed with SIGKILL (which cannot be caught, so the PID file wasn't cleaned up). The PID files live in /run (tmpfs), so they are automatically cleared on reboot. To clean them manually:

sudo rm -f /run/dvorak-*.pid

To uninstall the basic installation:

sudo make uninstall

To fully uninstall everything (basic + signal support), run:

# Stop all running services
sudo systemctl stop 'dvorak@*.service'
sudo systemctl stop 'dvorak-usb@*.service'
sudo systemctl disable 'dvorak@*.service'
sudo systemctl disable 'dvorak-usb@*.service'

# Remove binaries and scripts
sudo rm -f /usr/local/bin/dvorak
sudo rm -f /usr/local/bin/dvorak-start.sh
sudo rm -f /usr/local/bin/dvorak-signal.sh

# Remove udev rules and service files
sudo rm -f /etc/udev/rules.d/80-dvorak.rules
sudo rm -f /etc/systemd/system/dvorak@.service
sudo rm -f /etc/systemd/system/dvorak-usb@*.service

# Remove sudoers rule
sudo rm -f /etc/sudoers.d/dvorak-signal

# Clean up PID files
sudo rm -f /run/dvorak-*.pid

# Reload
sudo udevadm control --reload
sudo systemctl restart systemd-udevd.service
sudo systemctl daemon-reload

I used the following sites for inspiration:

• https://www.kernel.org/doc/html/v4.12/input/uinput.html
• https://www.linuxquestions.org/questions/programming-9/uinput-any-complete-example-4175524044/
• https://stackoverflow.com/questions/20943322/accessing-keys-from-linux-input-device
• https://gist.github.com/toinsson/7e9fdd3c908b3c3d3cd635321d19d44d