Get PHP config values

There is a PHP built-in function named ini_get that allow us to get the value of a configuration option. The value returned by the function present the value during runtime rather than the value defined in php.ini file. The value of a configuration option set on files can be overwritten, as mentioned before, by various means, such as web server. Some example are:

• By using PHP_VALUE on .htaccess or <VirtualHost> directive on Apache
• By using fastcgi_param PHP_VALUE on NGINX
• By code during execution, as example, using ini_set

To get the configuration value defined in php.ini, there's another built-in function called get_cfg_var, that actually do this. This function will ignore any values set by a webserver or during runtime and return the value set on the configuration file.

This function will not return configuration information set when the PHP was compiled, or read from an Apache configuration file. PHP get_cfg_var Manual

It can be possible that PHP is not loading values from the configuration file (php.ini), well in that case no value will be returned from get_cfg_var.

To check whether the system is using a configuration file, try retrieving the value of the cfg_file_path configuration setting. If this is available, a configuration file is being used. PHP get_cfg_var Manual

One thing to keep in mind is that defining a configuration option using php -d, even when php didn't load the values from php.ini this value will be available through get_cfg_var.

function get_config($key)
{
    if (get_cfg_var('cfg_file_path')) {
        return get_cfg_var($key);
    }

    return ini_get($key);
}

In the example above the function's goal is to return the value from php.ini, otherwise is going to fallback to retrieve the value present during runtime by using ini_get.