I don't quite grasp how the FUSE File operations are registered

[lquenti]

I would love to understand how go-fuse knows that the File struct implements the correct Read operation. Like, the Go equivalent to the C fuse_operations struct.

Also sorry if I somehow use the wrong words, I am quite new to go...

What I understand so far:

• main calls doMount for starting the fuse server
• in doMount, initFuseFrontend creates an RootNode, which "inherits" of Node, which implements Node level FUSE calls.
• This RootNode gets casted into a fs.InodeEmbedder, but since go interfaces work like vtables it still resolves to the new functions.
• Through this vtable functionality, the casted RootNode can be given to go-fuse via fs.Mount (in initGoFuse), and go-fuse can just do calls against this object and dynamic dispatch resolves it into the proper methods.

But through this method, only the Node methods (such as GETATTR) are defined. Methods auch as READ (that are defined on File) are still unclear to me.

Next, I tried to trace the FUSE operations via --fusedebug. For reading a file using cat, I got the following method trace:

• (Node) GETATTTR
• LOOKUP
• OPEN
• READ
• FLUSH
• RELEASE

I guess that in one of the early methods implemented by Node it somehow returns a File object so that go-fuse can call the file Read. But for the love of god, I can't find it.

Can you point me to where it happens?

PS: If it is a good motivation, I am probably adapting gocryptfs in my masters thesis and will definitely contribute back once I have something that makes sense for the public.

[lquenti]

Nevermind I found the fh, st, errno := NewFile(fd, cName, rn) in Create/Open (node_open_create.go)

[rfjakob]

Exactly. Also, https://nuetzlich.net/the-fuse-wire-protocol/ . That's some notes i took when writing gocryptfs.

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On Sun, 16 Feb 2025, 15:46 Lars Quentin, ***@***.***> wrote: Nevermind I found the fh, st, errno := NewFile(fd, cName, rn) in Create/ Open (node_open_create.go) — Reply to this email directly, view it on GitHub <#896 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACGA763J2XJCYSGDLZSUPT2QCQFVAVCNFSM6AAAAABXGUFPJKVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTEMRRGU3DONI> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>