Re: [Xenomai] [Xenomai-git] Philippe Gerum: copperplate: add configuration tunable for registry moint point

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

On Fri, Jan 02, 2015 at 04:10:27PM +0100, Gilles Chanteperdrix wrote:
> On Fri, Jan 02, 2015 at 10:05:03AM -0500, Lennart Sorensen wrote:
> > On Fri, Jan 02, 2015 at 01:51:33PM +0100, Gilles Chanteperdrix wrote:
> > > And as I explained, the standard sucks. /mnt on the distro I use
> > > contains the following directories:
> > > 
> > > cdrecorder
> > > cdrom
> > > dvd
> > > floppy
> > > hd
> > > memory
> > > tmp
> > > zip                 
> > > 
> > > and it puts the following text in /mnt/README
> > > 
> > > The purpose of the /mnt directory is to provide a place for the admin to
> > > mount block device temporarily.  Any of the subdirectories of /mnt may be
> > > used, or volumes may even be mounted directly on /mnt (which is the
> > > traditional way of doing things, though /mnt/tmp is also provided for
> > > the purpose of mounting any kind of volume temporarily).
> > > 
> > > See the /media directory also.
> > > 
> > > IOW: it leaves the choice to the user. What Philippe does is exactly
> > > the same: let the user choose whether he want to use the non
> > > standard sotlution that does not suck and that use to be a standard
> > > practice in Linux world, or the standard solution that sucks.
> > > 
> > > I thought we agreed this was a sensible solution.
> > 
> > So your README file even says the traditional way is to mount on top
> > of /mnt, which again means /mnt/xenomai stops working if you do what it
> > says is traditional in the README on that system.  Good reason not to
> > rely on anything in /mnt
> 
> You deliberately misread the README. It says that you may mount
> under whatever directory under /mnt makes sense for you OR that if
> you want, you can use /mnt. In the first case, using /mnt/xenomai
> will not break anything, in the second case yes, it will break
> things. But as I already said, I believe not many users are using
> the second solution because it inconvenient: if you do that, you
> have only one mount point for temporary thing, so the standard
> decided for you that you only mount one temporary thing at a time. I
> do not know about you, but I sometimes need to mount more than one
> thing temporarily, which is why I have plenty directories under
> /mnt.

And from a pure technical point of view, the perturbation induced by
a temporary mount on /mnt will be well, temporary, as soon as you
unmount, you will be able to access /mnt/xenomai again. And I doubt
the application itself will notice anything, as it will have kept
the /mnt/xenomai directory opened and so will be able to keep
accessing it, even if something else is mounted on top of /mnt.

-- 
					    Gilles.