turns out we no longer have SAVENAME, so still needs a little more work

I'll add NDINIT_AT as it's pretty important these days. I have no idea what the others do, though, and I don't want to speculate.

The flags are no longer u_long, it is uint64_t

I think the most useful bit from this manpage for most casual readers would be an example for the simple NDINIT with corresponding NDFREE_PNBUF() and error handling. Just such code

        struct nameidata nd;

	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, UIO_USERSPACE,
	    uap->path);
	if ((error = namei(&nd)) != 0)
		return (error);
	NDFREE_PNBUF(&nd);

would be a huge step in describing the interface.

Thank you, I'll add these later as I'm pressed for time.

The current text does not describe AUDITVNODE1 and again, I don't like to speculate. If you can describe the missing flags, I'll add them and your example in a subsequent commit.

I will handle this myself then.