Writing a filesystem in Swift / LoopFS question

[Matthew Burke]

I have just started a project to write a filesystem implementation in Swift.

The project will only ever be useful on macOS, otherwise I'd probably stick to C.

As a first step, I updated Gunnar Herzog's LoopFS example (from https://github.com/osxfuse/filesystems/tree/master/filesystems-swift/LoopbackFS) so that it would compile using Xcode 13/Swift 5.x (just a few minor changes needed). It works just fine.

Next, using the above as an example, I tried putting together a simple example that has a real stupid, simple implementation of just attributesOfItem, attributesOfFileSystem, and contentsOfDirectory. It compiles and runs. However, no file system gets mounted. I get the message "fuse: failed to exec mount program: Operation not permitted" in the console.

I'm hoping someone might have an idea of what the problem is. At the moment, I have the following two hypothesis which I will pursue over the weekend:

1. There is some permission setting, entitlement, etc that's set in Herzog's example that I'm overlooking

2. My toy example is too simple and I'm not implementing a necessary function.

I've posted the code as a gist at https://gist.github.com/profburke/b6eb8ece9da9fe1c266ebd2c88aec665

Thanks,

Matt