lib/MultiIniModifier.php
public function getValueOnMaster($name, $section = 0, $key = null)
    {
        return $this->master->getValue($name, $section, $key);
    }
public function getValueOnMaster($name, $section = 0, $key = null)
    {
        return $this->master->getValue($name, $section, $key);
    }
return the value of an option from the master ini file only.
If the option doesn't exist, it returns null.

@param string $name    the name of the option to retrieve
@param string $section the section where the option is. 0 is the global section
@param string $key     for option which is an item of array, the key in the array

@return mixed the value