As reported by Simone:
I was looking at version from 2017-09-15 but it's the same
on: http://man7.org/linux/man-pages/man2/statx.2.html
(2019-03-06)
There is reported (about the mask argument) after the list
of constants:
> Note that the kernel does not reject values in mask other
> than the above. Instead, it simply informs the caller which
> values are sup‐ ported by this kernel and filesystem via the
> statx.stx_mask field.
But as reported in the error values, there can be EINVAL if
mask has a reserved valued, and I found a check against
STATX__RESERVED in fs/stat.c for this. So if you use a that
bit (0x80000000U) the kernel will reject the value.
Probably is better to say that the kernel do not enforce the
use of only the listed values, but there are anyway reserved
values so and so you cannot put whatever you want on mask
(that apply to more values than UINT_MAX).
Reported-by: Simone Piccardi <piccardi@truelite.it>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
.TE
.in
.PP
-Note that the kernel does
+Note that, in general, the kernel does
.I not
reject values in
.I mask
other than the above.
+(For an exception, see
+.B EINVAL
+in errors.)
Instead, it simply informs the caller which values are supported
by this kernel and filesystem via the
.I statx.stx_mask
.B EINVAL
Reserved flag specified in
.IR mask .
+(Currently, there is one such flag, designated by the constant
+.BR STATX__RESERVED ,
+with the value 0x80000000U.)
.TP
.B ELOOP
Too many symbolic links encountered while traversing the pathname.