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Date:   Fri, 13 Mar 2020 09:48:57 -0700
From:   Jeremy Allison <jra@samba.org>
To:     Aleksa Sarai <cyphar@cyphar.com>
Cc:     Stefan Metzmacher <metze@samba.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        David Howells <dhowells@redhat.com>,
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        Ralph =?iso-8859-1?Q?B=F6hme?= <slow@samba.org>,
        Volker Lendecke <vl@sernet.de>
Subject: Re: [PATCH 01/14] VFS: Add additional RESOLVE_* flags [ver #18]
Message-ID: <20200313164857.GA17682@jeremy-acer>
Reply-To: Jeremy Allison <jra@samba.org>
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On Fri, Mar 13, 2020 at 08:59:01PM +1100, Aleksa Sarai wrote:
> 
> I have heard some folks asking for a way to create a directory and get a
> handle to it atomically -- so arguably this is something that could be
> inside openat2()'s feature set (O_MKDIR?). But I'm not sure how popular
> of an idea this is.

This would be very useful to prevent race conditions between making
a directory and EA's on it, as are needed by Samba for
DOS attributes and Windows/NFSv4 ACLS.