Re: [PATCH v6 0/4] MR6855: server: Fix renaming file to a hardlink of itself.

[Gabriel Ivăncescu (＠insn)]

On Sat Mar  8 13:58:45 2025 +0000, Jinoh Kang wrote:
> Better open the destination file's directory instead of the source
> file's directory.
> - We may only have search access to src directory but not read access (--x).
> - `O_PATH` is only available on Linux-like OSes. `O_SEARCH` is also not
>
> cross platform. Notably, macOS lacks `O_PATH`.
> To achieve this, we can switch the order: do stat() on src dirname, and
> open/fstat on dest dirname.
> If different directories, it must be a hardlink, so we simply remove the
> source and bail out. If the same, switching order did nothing, and we
> can proceed as normal.

Yeah, I hadn't realized that possibility, although probably rare in practice. I probably used this order so I can use `unlinkat` when removing the source, but it doesn't really matter, I'll swap.