dnd — Do Not Disturb

Process enforcer for shared machines. Monitors running processes and kills anything owned by users who aren't on the allowed list. Designed for honor-code reservation systems where some users don't follow the rules.

Quick start

No install needed — run directly with uvx:

# Allow everyone by default, block specific users:
uvx dnd-daemon allow '*'
uvx dnd-daemon block debopman

# Start the daemon (foreground, for testing):
uvx dnd-daemon run --dry-run

# Start for real:
uvx dnd-daemon run

Install

For persistent use, install globally with uv:

uv tool install dnd-daemon

Then use dnd directly:

dnd allow '*'
dnd block debopman
dnd run

Alternatively, install with pip:

pip install dnd-daemon

Commands

dnd run options

• --dry-run — log what would be killed without actually killing
• --daemon — fork into background
• --interval N — seconds between scans (default: 10)
• --verbose — debug-level logging

Wildcards

Use * in the allowed list to allow everyone by default. The blocked list always takes priority over the wildcard:

dnd allow '*'       # everyone is allowed
dnd block baduser   # ...except baduser

Configuration

User lists are stored in ~/.cache/dnd/:

~/.cache/dnd/
  allowed_users.txt
  blocked_users.txt
  dnd.log

Override with --allow-config and --block-config:

dnd --allow-config /path/to/allowed.txt list

Systemd service

sudo dnd install    # creates, enables, and starts the service
sudo dnd uninstall  # stops, disables, and removes the service
dnd status          # show service status

The service runs as the installing user with CAP_KILL for permission to terminate other users' processes. Config changes via dnd allow / dnd block are automatically picked up (the daemon reloads on SIGHUP).

How it works

1. Scans /proc every 10 seconds for all running processes
2. Skips system/service accounts (UID <= 999, known service names)
3. Checks each remaining process owner against the allowed/blocked lists
4. Sends SIGTERM, waits 5 seconds, then SIGKILL if still alive