From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 2 Jan 2015 15:16:25 +0100 From: Gilles Chanteperdrix Message-ID: <20150102141625.GD1492@daedalus> References: <54A672BA.8090209@web.de> <54A679D5.20903@xenomai.org> <54A67CD1.10103@web.de> <54A69D42.2010408@xenomai.org> <54A69BFA.7060405@web.de> <54A6A506.3060504@xenomai.org> <54A6A387.4010109@web.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <54A6A387.4010109@web.de> Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai] [Xenomai-git] Philippe Gerum: copperplate: add configuration tunable for registry moint point List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Xenomai On Fri, Jan 02, 2015 at 02:56:23PM +0100, Jan Kiszka wrote: > On 2015-01-02 15:02, Philippe Gerum wrote: > > On 01/02/2015 02:24 PM, Jan Kiszka wrote: > >> On 2015-01-02 14:29, Philippe Gerum wrote: > >>> On 01/02/2015 12:11 PM, Jan Kiszka wrote: > >>>> On 2015-01-02 11:58, Philippe Gerum wrote: > >>>>> On 01/02/2015 11:28 AM, Jan Kiszka wrote: > >>>>>> On 2015-01-01 18:43, xenomai-git-request@xenomai.org wrote: > >>>>>>> Module: xenomai-3 > >>>>>>> Branch: next > >>>>>>> Commit: d351f712bc9b03d621b454b55fe3e46a0000294a > >>>>>>> URL: http://git.xenomai.org/?p=xenomai-3.git;a=commit;h=d351f712bc9b03d621b454b55fe3e46a0000294a > >>>>>>> > >>>>>>> Author: Philippe Gerum > >>>>>>> Date: Thu Jan 1 18:15:36 2015 +0100 > >>>>>>> > >>>>>>> copperplate: add configuration tunable for registry moint point > >>>>>>> > >>>>>>> --enable-registry[=/registry-mount-point] > >>>>>>> > >>>>>>> Defaults to /mnt/xenomai. > >>>>>> > >>>>>> Do we really have to leave this as default? Then at least the debian > >>>>>> rules must be fixed to use a FHS-conforming path for distributed packages. > >>>>>> > >>>>> > >>>>> I don't care about which default is picked, really. I would agree with > >>>>> both options equally, i.e. using /mnt or /var/run, since /mnt has been a > >>>>> sensible and documented root for temporary mount points for ages in the > >>>>> *nix world, although I find /var/run a reasonable choice for > >>>>> non-persistent mount points as well. > >>>> > >>>> As I explained (and I wasn't alone with this view), this is not a matter > >>>> of taste but standard compliance: FHS requires us - as soon as we > >>>> consider Xenomai being part of the platform and not some self-written > >>>> admin script - to keep away from /mnt. You would have a hard time > >>>> finding a distro package that writes to /mnt without being explicitly > >>>> told by the admin. > >>> > >>> FHS 2.3 required volatile data to go to /var/run, and then Debian and > >>> others found out that it might not be the most usable choice, and went > >>> for /run+symlink to cope with legacy, until FHS 3.0 validates this > >>> arbitrary change eventually. > >>> > >>> So, I'm ok with FHS, but in that particular case, FHS has been wrong for > >>> years it seems. I'd rather discuss about usability then. The kind of > >>> issues I'd like to see people discussing instead of going ballistic for > >>> a freaking mount point would rather be: > >>> > >>> /var/run means tmpfs, which implies rw. > >>> /mnt means root fs, which might imply ro in some embedded cases. > >> > >> Thanks for reminding, that was one of my initial points in the > >> discussion. It derives from the ideas of the standard about the usage of > >> those mount points. > >> > > > > [...] > > > >>> It could be acceptable, or maybe there are arguments against requiring > >>> this. Please discuss about usability issues first and foremost. > >>> > > > > That part of the quote is important too. The fact that it departs from > > FHS is not a fundamental issue per se to me. What is important is > > whether departing is a problem for users, or transparent, or this > > improves usability. > > It obviously degraded the default experience: > - unexpected changes to /mnt > - unneeded persistent changes as /mnt is not intended to be used for > temporary system mount points, thus doesn't reside in tmpfs Both only for the small fractions of the users who do not routinely create directories under /mnt. > - conflicts on r/o file systems that hold /mnt This is a non issue: installing Xenomai requires doing a few things as administrator, creating /mnt/xenomai would just be one more. Using /var/run or /run on an embedded system that does not already have it creates the same issue. Really, not a problem. -- Gilles. -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 173 bytes Desc: not available URL: