Open should not be an interface exposed by Directory because it is the Archive thats implement the methed to open the directory. The service API of 3DS also implies this - Open is not a function of directory service, but is of FS main service
This is in line with what the hardware itself does.
It does this by splitting the initial directory opening into Directory.Open(), which will return false if a stat fails.
Then, Archive::OpenDirectory will return nullptr, and archive.cpp will return an error code .
bunnei