On Sun, Jul 07, 2019 at 12:57:35AM +1000, Aleksa Sarai wrote:
[...]

+/**
+ * Arguments for how openat2(2) should open the target path. If @extra is zero,
+ * then openat2(2) is identical to openat(2).
+ *
+ * @flags: O_* flags (unknown flags ignored).

What was the rationale for implementing this semantics?
Ignoring unknown flags makes potential extension of this new interface
problematic.  This has bitten us many times already, so ...

+ * @mode: O_CREAT file mode (ignored otherwise).
+ * @upgrade_mask: restrict how the O_PATH may be re-opened (ignored otherwise).
+ * @resolve: RESOLVE_* flags (-EINVAL on unknown flags).

... could you consider implementing this (-EINVAL on unknown flags) semantics
for @flags as well, please?


-- 
ldv