调用函数（Calling Functions）¶

如上所述，PHP 已经有帮我们做了很多事情，C 的扩展并不意味着我们要重新发明轮子。我们也要尽量避免使用 C 非常底层的特性。使用 PHP 函数帮助我们实现和 PHP 编程中类似的行为，这样我们就可以避免可能出现的错误。

The following code opens a file in C and write something on it. Its functionality is limited because it only works onlocal files:

Although both codes perform the same task, the former is more powerful as it could open a PHP stream, a file in a URL

or a local file. We can also write the same code using the PHP API, without losing functionality. However, theabove code is more familiar if we are primarily PHP developers.

原文: http://www.myleftstudio.com/internals/functions.html