libevent库基本介绍

     从翻译过来的一些文章，有误导的嫌疑的请对照原文。

     Libevent is a library for writing fast portable nonblocking IO. Its design goals are:

     libevent是一个可移值的写非阻塞IO的库，设计目标如下：

Portability：可移植的

Speed：速度

Scalability：可扩展的，可以处理超过1w个活动的连接。

Convenience：方便的。

libevent被分为如下几个模块：

evutil：通用的封装各个平台不同的网络实现的方法。

event and event_base：库的核心，提供不同平台的非阻塞IO抽象的API实现。

bufferevent：These functions provide a more convenient wrapper around Libevent’s event-based core. They let your application request buffered reads and writes, and rather than informing you when sockets are ready to do, they let you know when IO has actually occurred.

The bufferevent interface also has multiple backends, so that
it can take advantage of systems that provide faster ways to do
nonblocking IO, such as the Windows IOCP API.

evbuffer

This module implements the buffers underlying bufferevents, and provides functions for efficient and/or convenient access.

evhttp

A simple HTTP client/server implementation.

evdns

A simple DNS client/server implementation.

evrpc

A simple RPC implementation

When Libevent is built, by default it installs the following libraries:

libevent_core

All core event and buffer functionality. This library contains all the event_base, evbuffer, bufferevent, and utility functions.

libevent_extra

This library defines protocol-specific functionality that you may or may not want for your application, including HTTP, DNS, and RPC.

libevent

This library exists for historical reasons; it contains the contents of both libevent_core and libevent_extra. You shouldn’t use it; it may go away in a future version of Libevent.

The following libraries are installed only on some platforms:

libevent_pthreads

This library adds threading and locking implementations based on the pthreads portable threading library. It is separated from libevent_core so that you don’t need to link against pthreads to use Libevent unless you are actually using Libevent in a multithreaded way.

libevent_openssl

This library provides support for encrypted communications using bufferevents and the OpenSSL library. It is separated from libevent_core so that you don’t need to link against OpenSSL to use Libevent unless you are actually using encrypted connections.