On failure, the next level is tried. Every query starts at the first level again, so that one setting may be taken from the 3rd and one from the 1st level. Every application looks for an ini-file. The application tries to get the setting from the environment. An application can have some default settings decided at compile time, which allow the application to run even with no deployment settings.
Names are case insensitive.
Ini-files can have sections. If it is never called, a filename like the is assumed. If once the default is returned, successive calls always return this default value, even when called with different defaults. The number of the argument to return. Small incompatibility between StarOffice and Excel.