libevent is a

software library In computing, a library is a collection of resources that can be leveraged during software development to implement a computer program. Commonly, a library consists of executable code such as compiled functions and classes, or a library can ...

that provides asynchronous event notification. The libevent

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provides a mechanism to execute a callback function when a specific event occurs on a

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or after a timeout has been reached. libevent also supports callbacks triggered by signals and regular timeouts. libevent is meant to replace the event loop found in event-driven network servers. An application can just call event_dispatch() and then add or remove events dynamically without having to change the event loop. Currently, libevent supports /dev/poll, kqueue(2), POSIX select(2), Windows IOCP, poll(2), epoll(7) and Solaris event ports. It also has experimental support for real-time signals. The exposed event API is uniform over all of the supported platforms. As a result, libevent allows for

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application development and provides "the most scalable event notification mechanism available on an operating system". Using callbacks on signals, libevent makes it possible to write "secure" signal handlers as none of the user supplied signal handling code runs in the signal's context. libevent was created by Niels Provos, and is maintained primarily by Azat Khuzhin. It is released under a

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Notable applications

Some of the notable applications that take advantage of libevent are: *

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: Google's web browser (Mac and Linux versions) * Memcached: a high-performance, distributed memory object caching system * Transmission: an open-source BitTorrent client * ntpd: the Network Time Protocol

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* Tor: an anonymous Internet communication system * tmux: a terminal multiplexer

Alternatives

libev
* libuv * FAM
Boost Asio

Major version releases

*libevent 2.1 was released on April 3, 2012. *libevent 2.0 was released on April 17, 2009. *libevent 1.4 was released on November 11, 2007. *libevent 1.3 was released on February 15, 2007. *libevent 1.2 was released on October 15, 2006. *libevent 1.1 was released on May 14, 2005.

References

External links

{{Portal, Free and open-source software
Libevent web page

Libevent github repository

Libevent 2.0 book

C (programming language) libraries Events (computing) Free computer libraries Software using the BSD license