evtr

evtr is a terminal UI for inspecting Linux evdev input devices. Select a device from /dev/input/event*, then watch axes, relative motion, buttons, hats, joysticks, and touch state update live.

Screenshots

Selector

Gamepad

Touchpad

Mouse

Requirements

• Linux with evdev support
• Rust 1.85 or newer to build from source
• A terminal supported by crossterm
• Permission to read the selected /dev/input/event* node

If you see permission errors, grant your user read access to the relevant input devices. The exact group or udev rule is distro-specific.

Install And Run

Build the release binary from a checkout:

cargo build --release
./target/release/evtr

Install it into your Cargo bin directory from the local checkout:

cargo install --path .
evtr

Or run it directly without installing:

cargo run --release

Config

evtr reads config from:

• --config <path> when provided
• $XDG_CONFIG_HOME/evtr/config.toml when that file exists
• ~/.config/evtr/config.toml when the XDG file does not exist and the fallback file does

When XDG_CONFIG_HOME is set to an absolute path, --generate-config and --print-config-path use $XDG_CONFIG_HOME/evtr/config.toml even if the directory does not exist yet.

To generate a starter config file:

cargo run --release -- --generate-config

To write the starter config to a specific path:

cargo run --release -- --config /path/to/evtr.toml --generate-config

Other config-related flags:

• --print-config-path: print the path used for config generation
• --print-default-config: print the full default TOML template

Config is strict: unknown fields, invalid values, and duplicate/conflicting key bindings fail fast.

Config Reference

--print-default-config prints the complete supported config surface. The high-level sections are:

• selector: device sort order and selector page size
• monitor: page scroll size, startup focus, joystick inversion, and relative axis range
• theme.palette: five hex colors used by the TUI
• layout.selector and layout.monitor: panel sizing knobs
• keys.selector and keys.monitor: explicit key binding lists

Controls

• ? to open help

Failure Modes

evtr will report actionable errors when:

• /dev/input cannot be read
• Event nodes exist but cannot be opened
• The selected device stream ends or returns an I/O error
• Terminal initialization or redraw fails