From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <60f9bc7bde21dfaf422f2e6c3696bfad@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Newbie question
Date: Wed, 23 May 2007 14:36:01 -0400
From: Sape Mullender <sape@plan9.bell-labs.com>
In-Reply-To: <a09f8dc40705231125l4660b57bodc41f0cf5d44f2e4@mail.gmail.com>
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>        I'm a newbie in Plan 9.
> My problem is that I need to copy some files to the root ("/")
> directory, but when I try that, the system returns:
> 
> cp can't create /<filename>:
> '/<filename>' mounted directory forbids creation
> 
> I know (or better, I think) it's a permission problem,
> so how can I do to write in that directory?
> 
> Thanks to everybody in advance.

Plan 9 allows mounting multiple file systems at the same mount point,
one before or after the other.  If you have multiple file systems
mounted on, say, '/', then, when you create a file or directory
in '/', something has to tell the system in which of the mounted file
systems this file should be created.  Hence the -c flag on mount and bind.
	mount -c /srv/x mountpoint
of
	bind -c dir mountpoint
says that this is the file system in which new files should be created.
Needless to say, you can only do one -c mount or bind per mountpoint.

I bet your root file system isn't mounted with the -c flag.

	Sape