[This is preliminary documentation and subject to change.]
The Locator Tables Group of tables are used to locate files and applications. To search for a file first determine the file signature and then locate the file. The Locator tables are used to search the registry, installer configuration data, directory tree, or .ini files for the unique signature of a file. The file signature can then be checked in the Signature table to make sure a particular file is really the file being sought and not another file with the same name. If a record in a locator table does not contain a key into the Signature table, then the record refers to a directory and not a file.
The component controlling a file is found in the File table through the external key to the Component table. The installer resolves the location of a file through the Component table because every file belongs to one component. The location of a component is found through an external key in the Component table to the Directory table.
The location of an application is found by searching for files that make up the application. The installer also provides two tables for searching for previous versions of an application: the AppSearch table and the CCPSearch table.
The following tables make up the Locator tables group and are used to determine the file signature.