Carbon will fully support the Folder Manager.
DisposeFolderManagerNotificationUPP
Unix-specific call. You can use the usual FindFolder function (which supports UFS) in Carbon.
FolderManagerNotificationProcPtr
FolderManagerRegisterCallNotificationProcs
FolderManagerRegisterNotificationProc
FolderManagerUnregisterNotificationProc
InvalidateFolderDescriptorCache
InvokeFolderManagerNotificationUPP