Currently, once an OwnedFd has been passed to rustix::fs::Dir, there is no way to reuse it.

My usecase is to call rustix::fs::openat() and rustix::fs::statat() on it after I’m done with the iteration (or even during, I don’t think there is any issue with that since getdents64(2) is stateless).

My current solution is to call rustix::io::dup() on the fd before creating the Dir, but that shouldn’t be needed and wastes one fd. Another solution would be to rustix::fs::open() it again once the iteration is done, but that’s wasteful too.

rustix::fs::Dir::read_from has the same issue, it implements dup(2) manually by calling fcntl(4, F_GETFL) then openat(4, ".", …) with 4 being the fd being passed to it.

And since getdents64(2) is stateless, I believe there is no unsoundness issue with e.g. multiple rustix::fs::Dir being created around the same fd.