Specifications

E_ALL itself is effectively a combination of all the other error types. It could be replaced by the

other levels ORed together using the bitwise or operator (|).

E_COMPILE_ERROR |E_COMPILE_WARNING | E_USER_ERROR | E_USER_WARNING |

E_USER_NOTICE

Similarly, the default error reporting level could be specified by all error levels except notice

ORed together.

E_COMPILE_WARNING | E_USER_ERROR | E_USER_WARNING | E_USER_NOTICE

Altering the Error Reporting Settings

You can set the error reporting settings globally, in your php.ini file or on a per script basis.

To alter the error reporting for all scripts, you can modify these four lines in the default

php.ini file:

error_reporting = E_ALL & ~E_NOTICE

display_errors = On

log_errors = Off

track_errors = Off

The default global settings are to

• report all errors except notices

• output error messages as HTML to standard output

• not log error messages to disk

• not track errors, storing the error in the variable $php_errormsg

The most likely change you are to make is to turn the error reporting level up to E_ALL. This

will result in many notices being reported, for incidents that might indicate an error, or might

just result from the programmer taking advantage of PHP’s weakly typed nature and the fact

that it automatically initializes variables to 0.

While debugging, you might find it useful to set the error_reporting level higher. In produc-

tion code, if you are providing useful error messages of your own, it might be more profes-

sional looking to turn display_errors off and to turn log_errors on, while leaving the

error_reporting level high. You will then be able to refer to detailed errors in the logs if

problems are reported.

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