Unique file ID in FAT32

Question

Development environment: mobile app in Android

I'm looking for a way to uniquely identify files in a FAT32/VFAT file system (which has no inodes). I thought about hashing (SHA1?) the full path. The problem with this solution is that it doesn't support moving/renaming.

Is there something better, that will hold even when moving/renaming the file?

Thanks

Answer 1

Unfortunately FAT doesn't have Unique file IDs and when they are needed, various system components emulate them by maintaining the list of all files of the filesystem in memory (thus the ID is unique and valid only when the system is running).

Depending on what you control (either you have a filesystem driver, a filter or just a user-mode application) potentially you can do the same - have a list of files and provide some unique ID based on that list.