static String cachedStorageDirectory(DWORD pathIdentifier)
{
    static HashMap<DWORD, String> directories;

    HashMap<DWORD, String>::iterator it = directories.find(pathIdentifier);
    if (it != directories.end())
        return it->value;

    String directory = storageDirectory(pathIdentifier);
    directories.add(pathIdentifier, directory);

    return directory;
}

Unknown