[Feature request] expose filesystem inode information

[gustavo-iniguez-goya]

Hi!

Thanks for this package, really useful!

Currently, filesystem.Stat returns the information of a path in a fs.FileInfo struct: https://pkg.go.dev/github.com/diskfs/go-diskfs@v1.7.0/filesystem/ext4#FileSystem.Stat

This struct doesn't offer all the fields that for example the ext4 format has, like the inode.

There're some structs that could expose their internal fields:

go-diskfs/filesystem/ext4/directory.go

Line 15 in 63be039

type Directory struct {

go-diskfs/filesystem/ext4/directoryentry.go

Line 27 in 63be039

type directoryEntry struct {

go-diskfs/filesystem/ext4/file.go

Lines 10 to 11 in 63be039

	*directoryEntry
	*inode

https://github.com/diskfs/go-diskfs/blob/master/filesystem/ext4/inode.go#L110

For example, the stat command shows much more information than what the FileInfo struct offers:

~ $ stat .
  File: .
  Size: 4096      	Blocks: 8          IO Block: 4096   directory
 Device: 253,3	Inode: 3977042     Links: 7
 Access: (0775/drwxrwxr-x)  Uid: ( 1000/      ga)   Gid: ( 1000/      ga)
 Context: unconfined_u:object_r:user_home_t:s0
 Access: 2025-09-30 23:17:38.833369333 +0200
 Modify: 2025-09-30 23:17:37.589361321 +0200
 Change: 2025-09-30 23:17:37.589361321 +0200
 Birth: 2025-09-26 00:21:16.319751387 +0200

More like Stat_t: https://pkg.go.dev/golang.org/x/sys/unix#Stat_t

For some applications, having access to this information would be quite useful.

[deitch]

Yeah, this is a known issue in general. fs.FileInfo is the generic structure, meant to capture the most common set of information (least-common denominator? maybe). So for example fs.Stat() returns it.

If you want to get a more system-specific one, you call FileInfo.Sys() and get the underlying structure.

The goal here was to keep the fs.Stat() (even though it is an implementation in ext4) compatible across multiple filesystem implementations. It should have been made part of the Filesystem interface; kind of surprising that we never got around to it.

I think that the right solution here is to implement Sys() on the actual ext4.FileInfo struct implementation so you can get something more out of it, just like you do with normal os.Stat().

[gustavo-iniguez-goya]

I agree @deitch , calling ext4.Stat()...Sys() to get more details makes sense, so it stays consistent with how fs.Stat() works.

I hadn't tried to call ext4.Stat()...Sys(), but as expected, it returns nil.

[deitch]

I think the simplest route is to add these properties to ext4.FileInfo, and then have Sys() return itself.