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System.Linux.Btrfs.ByteString was created as an alternative to System.Linux.Btrfs, which uses FilePath to represent file paths. The problem with FilePath is that it requires for file paths to be encoded/decoded according to the current locale. This could potentially cause issues when a raw path contains byte sequences that are not valid according to the encoding used.

Fortunately, GHC provides a good solution to this issue via its file system encoding, which ensures that in a decode/encode cycle RawFilePath -> FilePath -> RawFilePath there will be no loss of information.

Therefore, I will drop System.Linux.Btrfs.ByteString from this library, unless I hear a good argument in favor of keeping it.

This is not entirely related with this package by maybe you have an idea of what is going on ... I need to know if a file is a symlink, since I don't want to call cloneRangeIfSame on a symlink, as that is useless and the ioctl fails. I was trying to use the functions in System.Posix.Files but they seem to be incapable of detecting simlinks in a read only snapshot. Do you have any idea what could cause this ? haskell/unix#79

When I try to run cloneRangeIfSame in files in read only subvolumes created with btrfs fi sub snapshot -r I get openFd: permission denied (Read-only file system) even when running the executable as root. Is it possible to make cloneRangeIfSame work in read-only snapshots ? In my tests the error comes up on the file in the file list of identical files, and looking at the code I see

withFd dstPath WriteOnly $ \fd

when opening the destination files. Perhaps this should also be ReadOnly ?

Hey,

I just stumbled over the following:

*Btrbkp> fromString ""
Just (fromString "*** Exception: Prelude.read: no parse

where I would expect to get a Nothing back. Do you consider fixing things like these in your library?

What do you think of switching to the uuid package? (http://hackage.haskell.org/package/uuid)