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Date: Thu, 3 May 2012 09:07:07 -0400
From: "Ted Ts'o" <tytso@mit.edu>
To: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>,
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        viro@zeniv.linux.org.uk, Richard Weinberger <richard@nod.at>,
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Subject: Re: [PATCH] open(2): document O_PATH
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On Thu, May 03, 2012 at 01:57:21PM +0530, Aneesh Kumar K.V wrote:
> 
> fstat won't work, but fstatat with an empty path name would work. O_PATH
> descriptors are suppose to be used as "location only descriptors". 
> We then extended the *at syscalls to work with EMPTY pathnames so that
> O_PATH descriptors can be used with readlink, fchownat and fstatat().
> This was done to enable us to do these operation on symlinks.
> (65cfc6722361570bfe255698d9cd4dccaf47570d)

Could you define explicitly what you mean by "EMPTY" pathnames?  Do
you mean a path name that doesn't exist?  (i.e., one of the
directories specified in the pathname does not currently exist in the
directory hierarchy visible to the process).

					- Ted

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