# Keyboard Input Blocker

A graphical application for Linux that toggles keyboard input blocking with a
single button. Perfect if your toddler likes to press a lot of buttons during
video calls.

## Features

- Simple one-button toggle interface built with PyQt6
- Disables/enables all keyboard input at the system level
- Status indicator showing current state
- Works on Wayland and X11

## Requirements

- Python 3.7+
- PyQt6
- evdev (Linux kernel input device library)

## Installation

### 1. Install dependencies

**On Ubuntu/Debian:**

```bash
sudo apt-get install python3 python3-pip libevdev-dev
pip install -r requirements.txt
```

**On Fedora:**

```bash
sudo dnf install python3 python3-pip libevdev-devel
pip install -r requirements.txt
```

**On Arch:**

```bash
sudo pacman -S python3 libevdev python-pyqt6 python-evdev
```

### 2. Run the application

The application requires elevated privileges to access input devices:

```bash
sudo -E python3 kb-block.py
```

Or make it executable:

```bash
chmod +x kb-block.py
sudo -E ./kb-block.py
```

## Usage

1. Launch the application with `sudo -E`
2. Click **"Block Keyboard"** to disable all keyboard input
   - The button turns red and shows **"Unblock Keyboard"**
   - Status shows "Keyboard BLOCKED ⚠"
3. Click **"Unblock Keyboard"** to re-enable keyboard input
   - The button returns to normal
   - Status shows "Keyboard enabled ✓"

**Note:** When keyboard is blocked, you'll need to use:

- Mouse to unblock via the button
- External input devices (if available)
- Or kill the process from another terminal: `sudo killall -9 python3` (or the
  specific PID)

## How it Works

The application uses the `evdev` library to grab input devices at the kernel level:

- `grab()` - Prevents the keyboard from sending any events
- `ungrab()` - Restores keyboard input

This works with both X11 and Wayland display servers.

## Permissions Note

The application requires `sudo` because it needs to directly access
`/dev/input/event*` devices.

If you want to run without `sudo`, you can add your user to the `input` group:

```bash
sudo usermod -a -G input $USER
# Log out and back in for the change to take effect
```

However, this is less secure as it grants all users in the input group broad
input device access.

## Troubleshooting

### No keyboard device found

- Ensure you're running with `sudo -E`
- Check that keyboard input devices exist: `ls -la /dev/input/event*`

### Permission denied"

- Run with `sudo -E`
- Or add your user to the input group (see Permissions Note above)

### Keyboard still responds

- Multiple keyboard devices may exist; the app grabs the primary one
- Try unblocking and re-blocking

## License

This project is licensed under the Zlib license (see [LICENSE](LICENSE) file for
more information).