On Thu, 01 Mar 2007 14:05:36 -0800
Jeremy Fitzhardinge [off-list ref] wrote:

Alan wrote:

quoted

A lot of people get confused about -ENOTTY, but it is the return for
attempting to use an ioctl on the wrong type of object, so this appears
to be quite correct.

This is a syscall though; ENOSYS is probably a better match.

ENOSYS indicates quite different things and ENOTTY is also used for
syscalls. I still think ENOTTY is correct.