Re: get_translator_{children,source} (v2)

[Samuel Thibault]

Justus Winter, le Thu 11 Jul 2013 18:09:03 +0200, a écrit :
> Samuel wrote:
> > Concerning storing the path, it's a bit sad to have to do that, and
> > it'll become wrong if one moves the mount points.  Another way would
> > be to make the client figure it out by itself from a port to the
> > mount point, much like glibc/sysdeps/mach/hurd/getcwd.c. It'll be
> > slower, but should be safer.
> 
> I agree that it's sad to do it like this, but I'm not convinced there
> is another way currently. I looked at getcwd(3) but the situation
> there is different, because getcwd(3) starts with a file_t referencing
> a directory.

Right, it doesn't have a ".." entry to get its parent.

Well, I'm not too concerned by stale paths, we can simply tell that
these are the "start" paths, which may have gone stale, but that'll be
very rare, and the user will still be able to use settrans -g.

> We discussed this in #hurd. Richard mentioned that moving mount points
> might not be a problem. He tried this on Linux and it returns EBUSY
> there.

But not when moving a parent directory, leading to a stale path in
/proc/mounts, seemingly not posing problems for decades.

Samuel