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Date:   Fri, 7 Aug 2020 17:23:05 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     "Enrico Weigelt, metux IT consult" <info@metux.net>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
Subject: Re: srvfs: file system for posting open file descriptors into fs
 namespace
Message-ID: <20200807162305.GT1236603@ZenIV.linux.org.uk>
References: <55ef0e9a-fb70-7c4a-e945-4d521180221c@metux.net>
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On Fri, Aug 07, 2020 at 01:09:30PM +0200, Enrico Weigelt, metux IT consult wrote:
> Hello folks,
> 
> 
> here's the first version of my "srvfs" implementation - a synthentic
> filesystem which allows a process to "publish" an open file descriptor
> into the file system, so other processes can continue from there, with
> whatever state the fd is already in.
> 
> This is a concept from Plan9. The main purpose is allowing applications
> "dialing" some connection, do initial handshakes (eg. authentication)
> and then publish the connection to other applications, that now can now
> make use of the already dialed connection.

Yeah, but...  Linux open() always gets a new struct file instance; how
do you work around that?  Some variant of ->atomic_open() API change?
Details, please.