> ## Documentation Index
> Fetch the complete documentation index at: https://docs.otter-shell.org/llms.txt
> Use this file to discover all available pages before exploring further.

# otter-lock

> Session lock screen with PAM login, fingerprint auth, and optional clock.

`otter-lock` locks the session over `ext-session-lock-v1`. It covers every output when `loginctl lock-session` runs or [otter-idle](/desktop/otter-idle) triggers a lock.

## Usage

Lock the session:

```bash theme={null}
loginctl lock-session
```

Bind this to a compositor hotkey. For example `Super+L`.

logind starts `otter-lock` when a lock is requested. Do not run it as a persistent daemon.

## Configuration

Config file: `~/.config/otter-shell/otter-lock.conf`

```conf theme={null}
blur_radius = 9
clock_font_size = 72
date_font_size = 18
font_size = 14
dialog_width = 360
enable_fingerprint = true
show_clock = true
show_avatar = true
pam_service = "otter-lock"
screensaver_image = "/usr/share/otter-shell/lock/otter-shell.png"
```

Colors inherit from [theme.conf](/configuration/themes) when not set.

### Wallpaper background

When [otter-wallpaper](/desktop/otter-wallpaper) is running, the lockscreen reads `$XDG_RUNTIME_DIR/otter-shell/wallpaper-state` for the same wallpaper behind the lock UI.

## Authentication

* PAM password authentication (`pam_service` config key)
* Fingerprint via fprintd when `enable_fingerprint = true`
* Build with `-Denable_pam=false` or `-Denable_dbus=false` disables auth features (developer builds only)

## Keybindings

| Key    | Action                    |
| ------ | ------------------------- |
| Enter  | Submit password           |
| Escape | Cancel fingerprint prompt |