evtest
Input device event monitor and query tool
TLDR
List all detected input devices
$ sudo evtest
Display events from a specific device$ sudo evtest /dev/input/event[number]
Grab device exclusively (prevent other apps from receiving events)$ sudo evtest --grab /dev/input/event[number]
Query state of a specific key or button$ sudo evtest --query /dev/input/event[number] EV_KEY [KEY_A]
SYNOPSIS
evtest [--grab] /dev/input/eventXevtest --query /dev/input/eventX eventtype eventcode
DESCRIPTION
evtest displays information from input device drivers using the Linux input subsystem. In capture mode, it shows all events supported by the device and then monitors it to display all generated events like key presses, mouse movements, and touch events.In query mode, it performs a one-shot query of the state of a specific key, switch, sound, or LED value.
PARAMETERS
--grab
Grab device exclusively using EVIOCGRAB, preventing other processes from receiving events.--query device type code
Query state of a specific key/button/switch. Type can be EVKEY, EVSW, EVSND, EVLED or a numeric value. Returns exit code 0 if unset, 10 if set.
INSTALL
sudo apt install evtest
sudo dnf install evtest
sudo pacman -S evtest
sudo apk add evtest
sudo zypper install evtest
nix profile install nixpkgs#evtest
CAVEATS
Requires root privileges to read from /dev/input/ devices. Grabbing a device prevents other applications from receiving events until evtest quits.
