event的作用是支持在php里使用libevent

libevent的作用是提供I/0编程支持

先需要安装libevent

yum install libevent-devel

然后安装event

pecl install event

configure: error: Please reinstall the event library, or provide the installation prefix via --with-event-libevent-dir option

在安装时指定libevent的安装目录

libevent installation prefix [/usr] : /usr/local

configure: error: Cannot find OpenSSL's <evp.h> 

yum install openssl openssl-devel

configure: error: bufferevent_openssl_get_ssl not found in event_openssl lib

安装好openssl后重装libevent

undefined symbol: php_sockets_le_socket in Unknown on line 0

在/etc/php.d/socket.ini 里

在extension=sockets.so 后面写入

extension=event.so //因为event必须后于sockets加载

event安装完成