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+Copyright (C) 2026 Nicolás A. Ortega Froysa <nicolas@ortegas.org>
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
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+# 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).
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+#!/usr/bin/env python3
+# Copyright (C) 2026 Nicolás Ortega Froysa <nicolas@ortegas.org> All rights reserved.
+# Author: Nicolás Ortega Froysa <nicolas@ortegas.org>
+#
+# This software is provided 'as-is', without any express or implied
+# warranty. In no event will the authors be held liable for any damages
+# arising from the use of this software.
+#
+# Permission is granted to anyone to use this software for any purpose,
+# including commercial applications, and to alter it and redistribute it
+# freely, subject to the following restrictions:
+#
+# 1. The origin of this software must not be misrepresented; you must not
+#    claim that you wrote the original software. If you use this software
+#    in a product, an acknowledgment in the product documentation would be
+#    appreciated but is not required.
+#
+# 2. Altered source versions must be plainly marked as such, and must not be
+#    misrepresented as being the original software.
+#
+# 3. This notice may not be removed or altered from any source
+#    distribution.
+
+"""
+Keyboard Input Blocker for X11/Wayland
+
+A graphical application that toggles keyboard input on/off.
+Requires: PyQt6, evdev
+"""
+
+import sys
+import os
+from pathlib import Path
+from PyQt6.QtWidgets import QApplication, QMainWindow, QPushButton, QVBoxLayout, QWidget, QLabel, QMessageBox
+from PyQt6.QtCore import Qt, QThread, pyqtSignal
+from PyQt6.QtGui import QFont
+import evdev
+from evdev import InputDevice, list_devices
+
+
+class KeyboardBlockerThread(QThread):
+    """Thread to handle keyboard grabbing in the background."""
+
+    error_occurred = pyqtSignal(str)
+    grabbed = pyqtSignal()
+    released = pyqtSignal()
+
+    def __init__(self):
+        super().__init__()
+        self.keyboard_device = None
+        self.is_blocking = False
+        self.should_stop = False
+
+    def find_keyboard_device(self):
+        """Find the keyboard input device."""
+        devices = [InputDevice(path) for path in list_devices()]
+
+        # Look for keyboard devices
+        keyboard_devices = []
+        for device in devices:
+            try:
+                caps = device.capabilities()
+                # Check if device has KEY capability (keyboards have this)
+                if evdev.ecodes.EV_KEY in caps:
+                    # Prefer devices with common keyboard names
+                    if any(name in device.name.lower() for name in ['keyboard', 'input', 'wacom']):
+                        keyboard_devices.append(device)
+            except:
+                continue
+
+        if keyboard_devices:
+            return keyboard_devices[0]
+
+        # Fallback: return first device with KEY capability
+        for device in devices:
+            try:
+                caps = device.capabilities()
+                if evdev.ecodes.EV_KEY in caps:
+                    return device
+            except:
+                continue
+
+        return None
+
+    def grab_keyboard(self):
+        """Grab the keyboard device to block input."""
+        try:
+            self.keyboard_device = self.find_keyboard_device()
+
+            if not self.keyboard_device:
+                self.error_occurred.emit(
+                    "No keyboard device found. You may need to run with sudo."
+                )
+                return False
+
+            # Grab the device (this requires appropriate permissions)
+            self.keyboard_device.grab()
+            self.is_blocking = True
+            self.grabbed.emit()
+            return True
+
+        except PermissionError:
+            self.error_occurred.emit(
+                "Permission denied. Please run with elevated privileges (sudo)."
+            )
+            return False
+        except Exception as e:
+            self.error_occurred.emit(f"Error grabbing keyboard: {str(e)}")
+            return False
+
+    def release_keyboard(self):
+        """Release the keyboard device to allow input."""
+        try:
+            if self.keyboard_device:
+                self.keyboard_device.ungrab()
+                self.is_blocking = False
+                self.released.emit()
+                return True
+        except Exception as e:
+            self.error_occurred.emit(f"Error releasing keyboard: {str(e)}")
+        return False
+
+
+class KeyboardBlockerApp(QMainWindow):
+    """Main application window for keyboard blocker."""
+
+    def __init__(self):
+        super().__init__()
+        self.blocker_thread = KeyboardBlockerThread()
+        self.is_keyboard_blocked = False
+
+        # Connect thread signals
+        self.blocker_thread.grabbed.connect(self.on_keyboard_grabbed)
+        self.blocker_thread.released.connect(self.on_keyboard_released)
+        self.blocker_thread.error_occurred.connect(self.on_error)
+
+        self.init_ui()
+
+    def init_ui(self):
+        """Initialize the user interface."""
+        self.setWindowTitle("Keyboard Input Blocker")
+        self.setGeometry(100, 100, 400, 200)
+
+        # Create central widget and layout
+        central_widget = QWidget()
+        self.setCentralWidget(central_widget)
+        layout = QVBoxLayout(central_widget)
+
+        # Title label
+        title_label = QLabel("Keyboard Input Blocker")
+        title_font = QFont()
+        title_font.setPointSize(14)
+        title_font.setBold(True)
+        title_label.setFont(title_font)
+        layout.addWidget(title_label)
+
+        # Status label
+        self.status_label = QLabel("Status: Keyboard enabled")
+        layout.addWidget(self.status_label)
+
+        # Toggle button
+        self.toggle_button = QPushButton("Block Keyboard")
+        self.toggle_button.setMinimumHeight(50)
+        self.toggle_button.setFont(QFont("Times", 12))
+        self.toggle_button.clicked.connect(self.toggle_keyboard)
+        layout.addWidget(self.toggle_button)
+
+        # Info label
+        info_label = QLabel(
+            "Click the button to toggle keyboard input blocking.\n"
+            "Note: This application may require elevated privileges (sudo)."
+        )
+        info_font = QFont()
+        info_font.setPointSize(9)
+        info_label.setFont(info_font)
+        layout.addWidget(info_label)
+
+        layout.addStretch()
+
+    def toggle_keyboard(self):
+        """Toggle keyboard blocking on/off."""
+        if self.is_keyboard_blocked:
+            self.blocker_thread.release_keyboard()
+        else:
+            self.blocker_thread.grab_keyboard()
+
+    def on_keyboard_grabbed(self):
+        """Handle keyboard grabbed signal."""
+        self.is_keyboard_blocked = True
+        self.toggle_button.setText("Unblock Keyboard")
+        self.toggle_button.setStyleSheet("background-color: #ff6b6b;")
+        self.status_label.setText("Status: Keyboard BLOCKED ⚠")
+
+    def on_keyboard_released(self):
+        """Handle keyboard released signal."""
+        self.is_keyboard_blocked = False
+        self.toggle_button.setText("Block Keyboard")
+        self.toggle_button.setStyleSheet("")
+        self.status_label.setText("Status: Keyboard enabled ✓")
+
+    def on_error(self, message):
+        """Handle error signal."""
+        QMessageBox.critical(self, "Error", message)
+
+    def closeEvent(self, a0):
+        """Ensure keyboard is released when closing."""
+        if self.is_keyboard_blocked:
+            self.blocker_thread.release_keyboard()
+        self.blocker_thread.quit()
+        self.blocker_thread.wait()
+        a0.accept()
+
+
+def main():
+    """Main entry point."""
+    app = QApplication(sys.argv)
+    window = KeyboardBlockerApp()
+    window.show()
+    sys.exit(app.exec())
+
+
+if __name__ == "__main__":
+    main()
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+PyQt6>=6.0.0
+evdev>=1.6.0