你如何定义术语“失败的功能”？

Question

In a presentation about Zend Server, the author lists the features of Zend Monitor. One of these features is called:

• Zend Monitor will watch your application for failing functions

What does this mean, if you subtract error and exception monitoring? How can you detect a failing function, if not through and error or uncaught exception?

Answer 1

Hope it's not too late to give an answer "from the makers" (I work on Zend Server), but the "Function Error" events (as well as "Database Error" events) are triggered when one of the watched functions (defined in the monitoring rule) returns boolean FALSE.

This follows a pattern which is common especially in the more "traditional" PHP APIs (e.g. mysql, curl, openssl etc.) where some function will simply return FALSE to indicate failure, and you then are required to call a "get_errors()" function to see what went wrong.

This is unlike "normal" PHP errors which are E_ERROR, E_WARNING etc. error types, which some other PHP functions will raise when something fails.