ZEND PHP 5 Certification STUDY GUIDE

PHP Basics ” 33
Compile-time errors
Fatal errors
Recoverable errors
Warnings
Notices
Errors detected by the parser while it is compiling
a script. Cannot be trapped from within the script
itself.
Errors that halt the execution of a script. Cannot
be trapped.
Errors that represent significant failures, but can
still be handled in a safe way.
Recoverable errors that indicate a run-time fault.
Do not halt the execution of the script.
Indicate that an error condition occurred, but is
not necessarily significant. Do not halt the
execution of the script.
As you can see, it is not always possible for a script to detect a fault and recover from
it. With the exception of parsing errors and fatal errors, however, your script can at
least be advised that a fault has occurred, thus giving you the possibility to handle
failure gracefully.
Error Reporting
By default, PHP reports any errors it encounters to the script’s output. Unless you
happen to be in a debugging environment, this is rarely a feature that you will want
to take advantage of: allowing users to see the errors that your scripts encounter is
not just bad form—it could be a significant security issue.
Luckily, several configuration directives in the php.ini file allow you to finetune
how—and which—errors are reported. The most important ones are
error_reporting, display_errors and log_errors.
The error_reporting directive determines which errors are reported by PHP. A series
of built-in constants allow you to prevent PHP from reporting errors beneath a
certain pre-defined level. For example, the following allows for the reporting of all
errors, except notices:
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)
error_reporting=E_ALL & ~E_NOTICE