Portable Directory Monitor: Instant Alerts for File Additions, Modifications, and Deletions

Lightweight Portable Directory Monitor for USB and External Drives

What it is
A small, portable tool that watches directories on USB sticks and external drives for file changes (creates, modifies, deletes, renames) without requiring installation.

Core features

• Portability: Runs directly from removable media—no install or admin rights required.
• Real-time monitoring: Detects file system events immediately using native OS file-watch APIs (inotify on Linux, ReadDirectoryChangesW on Windows, FSEvents on macOS).
• Low resource usage: Minimal CPU/RAM footprint to avoid slowing down host systems.
• Selective watching: Monitor specific folders, subfolder depth, and file patterns (wildcards, extensions).
• Notifications: Optional on-screen alerts, log files, or app-level popups; configurable verbosity.
• Logging & export: Append-only logs with timestamps; export to plain text, CSV, or JSON for audit or analysis.
• Safe operation on removable media: Handles sudden disconnects gracefully, avoids caching that risks data loss.
• Config files: Portable settings stored alongside the executable so preferences travel with the drive.

Use cases

• Track changes to files on shared USB drives.
• Audit edits to configuration or log files on external disks.
• Detect accidental deletions or unwanted modifications on portable backups.
• Lightweight folder-watching for field technicians using laptops without installing software.

Security & reliability considerations

• Avoid running untrusted executables from unknown USBs.
• Ensure logs on the drive are encrypted if they contain sensitive filenames or metadata.
• Tool should handle media removal events and resume watching when the drive is reconnected.
• Prefer read-only operations when used on sensitive systems to minimize footprint.

Minimal implementation outline (cross-platform)

1. Use native file-watch API per OS for efficiency.
2. Provide a small command-line and optional GUI front end.
3. Store settings in a local config file on the drive.
4. Write append-only timestamped logs; offer CSV/JSON export.
5. Implement safe shutdown and reconnection handling.

If you want, I can draft a short user guide, a sample config file, or a minimal cross-platform script to demonstrate core functionality.