fuse_file_info, File Handle, and open()

[Trendyne]

libfuse provides a fh field in the fuse_file_info struct which is passed to most functions
https://libfuse.github.io/doxygen/structfuse__file__info.html#a45314d0b92a8d4c9de33d996aa59ada8

File handle id. May be filled in by filesystem in create, open, and opendir(). Available in most other file operations on the same file handle.

These are needed if you want to keep data consistent across chunked read()s or write()s where the data might be non-static for the path.
Adding overloads that provide at least the fh and an open() method in the Operations interface, as well as a close() for cleanup, would allow a wider range of applications than just static content per path.

[CyberShadow]

Yeah, I think the high-level D wrapper ought to be rewritten to take advantage of that.

For now I would suggest just using the D bindings to the C API. It is better documented (just see the C API docs), and the D wrapper doesn't add all that much value.

Here are some examples of using the C API in D programs I wrote:
https://github.com/CyberShadow/ripfs/blob/466dae1fb7ab16ad4dc4948a091fd4551499f5af/ripfs.d#L437-L575
https://github.com/CyberShadow/thincow/blob/b86c4b5aa8e4e38bde2b87a690bda828cc667a1a/source/thincow/fuse.d#L93-L411