Re: [PATCH] man/man2/fanotify_mark.2: AT_FDCWD plus NULL path doesn't work

[Amir Goldstein]

On Fri, May 29, 2026 at 7:27 PM Jann Horn <jannh@xxxxxxxxxx> wrote:
>
> The fanotify_mark.2 manpage claims that AT_FDCWD works with a NULL path,
> but there is no kernel code for that - in fanotify_find_path(), in the
> `if (filename == NULL)` block, the fd is only used for a normal FD
> lookup.
>
> This was also already the case when this manpage was written back in
> 2014, so remove the bogus documentation.
>
> Fixes: c200b422d ("fanotify_mark.2: New page documenting fanotify_mark(2)")
> Signed-off-by: Jann Horn <jannh@xxxxxxxxxx>

Hah,  never noticed this.
Apparently, hallucinations already existed in 2014 :D

Acked-by: Amir Goldstein <amir73il@xxxxxxxxx>

> ---
>  man/man2/fanotify_mark.2 | 8 --------
>  1 file changed, 8 deletions(-)
>
> diff --git a/man/man2/fanotify_mark.2 b/man/man2/fanotify_mark.2
> index e561ffd21..a3b77537c 100644
> --- a/man/man2/fanotify_mark.2
> +++ b/man/man2/fanotify_mark.2
> @@ -560,14 +560,6 @@ defines the filesystem object to be marked.
>  .IP \[bu]
>  If
>  .I path
> -is NULL, and
> -.I dirfd
> -takes the special value
> -.BR AT_FDCWD ,
> -the current working directory is to be marked.
> -.IP \[bu]
> -If
> -.I path
>  is absolute, it defines the filesystem object to be marked, and
>  .I dirfd
>  is ignored.
>
> ---
> base-commit: 9db8ca91f920b9aba40ed68de6b8da0ca9dbefaa
> change-id: 20260529-fan-mark-cwd-1c760106eff9
>
> Best regards,
> --
> Jann Horn <jannh@xxxxxxxxxx>
>