PHP Manual

Runtime Configuration

The behaviour of these functions is affected by settings in php.ini.

**Network Configuration Options**
Name	Default	Changeable	Changelog
define_syslog_variables	"0"	PHP_INI_ALL	Deprecated in PHP 5.3.0. This deprecated feature will certainly be removed in the future.

For further details and definitions of the PHP_INI_* modes, see the Where a configuration setting may be set.

Here's a short explanation of the configuration directives.

define_syslog_variables boolean: Whether or not to define the various syslog variables (e.g. $LOG_PID, $LOG_CRON, etc.). Turning it off is a good idea performance-wise. At runtime, you can define these variables by calling define_syslog_variables().