Subject: Re: Feature request, "create on mount" to create mount point
 directory on mount, implied remove on unmount
From: jon <jon@jonshouse.co.uk>
Reply-To: jon@jonshouse.co.uk
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Valdis.Kletnieks@vt.edu, coreutils@gnu.org, linux-kernel@vger.kernel.org
In-Reply-To: <20150705142936.GW17109@ZenIV.linux.org.uk>
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	 <20150705142936.GW17109@ZenIV.linux.org.uk>
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Date: Sun, 05 Jul 2015 16:46:50 +0100
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On Sun, 2015-07-05 at 15:29 +0100, Al Viro wrote:
> On Sat, Jul 04, 2015 at 11:48:28PM +0100, jon wrote:
> 
> > Yes, but like I say automount is normally based on an event. I am simply
> > talking about a flag/switch that can be used for optional implied
> > mkdir,rmdir around calls to mount() unount() - nothing more, nothing
> > less !
> 
> umount(2) is not the only way for mount to detached from a mountpoint.
> There's exit(2) as well - when the last process in a namespace exits, it
> gets dissolved.  What should happen upon those?  Even more interesting question
> is what should happen if you do such mount, then clone a process into a new
> namespace and have it exit.  Should _that_ rmdir the hell out of that
> mountpoint (presumably detaching everything mounted on it in all namespaces)?
> 

I should have titled it "Feature request from a simple minded user"

I have not the slightest idea what you are talking about.  

When I learnt *nix it did not have "name spaces" in reference to process
tables.  I understand the theory of VM a bit, the model in my mind each
"machine", be that one kernel on a true processor or a VM instance has
"a process table" and "a file descriptor table" etc - anything more is
beyond my current level of knowledge.

Containers for example are something I dont understand in two ways. I
dont truely understand the theory, I also dont understand why in a world
of true VM  someone would want to make something as complex as linux
even more complex using containers for what seems little or no benefit.


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