On Wed, Apr 26, 2017 at 12:35:08PM +0100, David Howells wrote: > AT_EMPTY_PATH wasn't there back in 2010. I could eliminate the: > > statx(fd, NULL, 0, ...); > > option in favour of: > > statx(fd, "", AT_EMPTY_PATH, ...); > > Any thoughts either way, Al? > > It would seem that AT_EMPTY_PATH should be redundant, though, since you can > just set the pathname pointer to NULL.
NULL pathname pointer means an error for a lot of existing syscalls, so if you want to turn them into wrappers for ...at() ones at libc level, you'd need to do special-casing of NULL both kernel-side and in libc wrappers. Requiring "" + AT_EMPTY_PATH means a single dereference of userland pointer. OTOH, that's not a terrible burden...
