From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andreas Dilger <adilger@sun.com>
Subject: Re: [PATCH] vfs: new O_NODE open flag
Date: Mon, 28 Sep 2009 09:21:28 -0600
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To: Miklos Szeredi <miklos@szeredi.hu>
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On Sep 28, 2009  12:25 +0200, Miklos Szeredi wrote:
> BTW I just checked, and it is possible to re-open or promote an fd
> opened with O_NODE like this:
> 
> 	char tmp[64];
> 
> 	fd = open(filename, O_NODE | O_NOACCESS);
> 	/* ... */
> 	sprintf(tmp, "/proc/self/fd/%i", fd);
> 	fd_rw = open(tmp, O_RDWR);
> 
> Now fd_rw is guaranteed to refer to the same inode as fd.

It seems very unpleasant to require applications using O_NODE to
reopen files using /proc.

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.