Definition
Snarl is a free, open‑source global notification system for Microsoft Windows that enables applications to display translucent, alpha‑blended messages on the screen. It is designed to provide unobtrusive alerts without stealing focus from the active window or forcing the taskbar to become visible.
Overview
Developed by the Snarl Team, the software was first released in 2007 and reached its latest stable version (3.1) on 14 March 2014. It is licensed under the 2‑clause BSD license and runs on Windows 2000, XP, Vista, and Windows 7, supporting both 32‑bit and 64‑bit environments. Snarl’s architecture is based on the Windows window‑messaging API, allowing integration with a wide range of programming languages, from low‑level C to high‑level environments such as Visual Basic 6 and .NET. The system can display multiple notifications simultaneously, with newer messages stacked above or below existing ones. Users may dismiss a notification by clicking on it, or let it disappear automatically after a configurable timeout.
Etymology/Origin
The name “Snarl” likely alludes to the English word snarl, meaning a short, sharp sound or a tangled mass, evoking the notion of brief, attention‑drawing alerts. No official statement from the developers confirms the precise origin of the name.
Characteristics
- Notification display: Alpha‑blended, semi‑transparent pop‑up windows that can be positioned anywhere on the screen.
- Multi‑message handling: Supports concurrent display of several notifications, with dynamic stacking.
- Interaction: Allows applications to receive callbacks when users click on a notification.
- Customization: Position, duration, icons, and content can be programmatically altered; developers can update or explicitly remove messages.
- Unicode support: Fully compatible with Unicode text, enabling internationalized content.
- Broad compatibility: Works on Windows 2000 through Windows 7, on both 32‑bit and 64‑bit systems.
- Extensibility: Provides a simple API based on Windows messages, making it accessible to many languages; a variety of plug‑ins exist for popular applications (e.g., Firefox, foobar2000, iTunes, Launchy, mIRC, Pidgin, Spotify, Winamp, Thunderbird).
- License: Distributed under the permissive 2‑clause BSD license, allowing free use, modification, and redistribution.
Related Topics
- Growl (software) – A similar notification system for macOS that inspired Snarl.
- Windows toast notifications – The native notification framework introduced in later Windows versions.
- System tray utilities – Tools that manage icons and alerts in the Windows taskbar area.
- NotifyOSD, Toaster, Snarl‑compatible plug‑ins – Other third‑party notification solutions for various operating systems.