PHP Extension 读书笔记

PHP's core is made up of two separate pieces. At the lowest levels you findthe Zend Engine (ZE). ZE handles parsing a human-readable script intomachine-readable tokens, and then executing those tokens within a process space. ZEalso handles memory management, variable scope, and dispatching function calls. Theother half of this split personality is the PHP core. PHP handlescommunication with, and bindings to, the SAPI layer (Server ApplicationProgramming Interface, also commonly used to refer to the host environment - Apache,IIS, CLI, CGI, etc). It also provides a unified control layer forsafe_mode and open_basedir checks, as well as the streamslayer which associates file and network I/O with userspace functions likefopen(), fread(), and fwrite().

 

[http://devzone.zend.com/article/1021-Extension-Writing-Part-I-Introduction-to-PHP-and-Zend]