Tevent

Tevent is an open-source event-handling library designed to support event-driven programming in C. It provides a portable, lightweight abstraction for an event loop that can monitor I/O readiness, timers, and signals, allowing programs to react to multiple asynchronous sources without blocking.

Originating in the Samba project, tevent was created to provide a reusable, cross-platform event notification mechanism. It is distributed as a standalone library and has been adopted by other software that needs a small, self-contained event loop.

Design and API: The core is an event context object that holds state for the loop. Applications register watchers or callbacks for file descriptors, timers, or signals. The loop runs, dispatching callbacks when events fire; loops can be nested or integrated with other threading models. The library emphasizes portability and minimal dependencies.

Usage: Initialize a tevent context, install event sources, then run the loop; exit when all work is complete. Callbacks handle I/O events, timers, or asynchronous tasks. The design supports modular and asynchronous operation without requiring a large runtime.

Relation and status: Tevent remains in use in legacy and some current projects that rely on a concise C event loop. Its lightweight footprint and portability make it suitable for embedded systems and cross-platform software that prefer not to depend on larger event libraries.