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Date:   Wed, 1 Aug 2018 12:28:49 -0400
From:   "Theodore Y. Ts'o" <tytso@mit.edu>
To:     David Howells <dhowells@redhat.com>
Cc:     viro@zeniv.linux.org.uk, linux-api@vger.kernel.org,
        torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org,
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Subject: Re: [PATCH 1/5] vfs: syscall: Add fsinfo() to query filesystem
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On Wed, Aug 01, 2018 at 05:14:01PM +0100, David Howells wrote:
> 
> Some attributes (such as the servers backing a network filesystem) can have
> multiple values.  These can be enumerated by setting params->Nth and
> params->Mth to 0, 1, ... until ENODATA is returned.

How does the caller know whether or not a particular attribute has
multiple values?  Is that a fundamental attribute of a particular
attribute?  (e.g., the documentation for each attribute must state
whether or not that attribute returns multiple attributes or not)

	       	    	      	      - Ted