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Date:   Wed, 11 Jul 2018 09:51:59 -0600
From:   Jonathan Corbet <corbet@lwn.net>
To:     David Howells <dhowells@redhat.com>
Cc:     viro@zeniv.linux.org.uk, linux-api@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 24/32] vfs: syscall: Add fsopen() to prepare for
 superblock creation [ver #9]
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On Tue, 10 Jul 2018 23:44:09 +0100
David Howells <dhowells@redhat.com> wrote:

> 	sfd = fsopen("ext4", FSOPEN_CLOEXEC);
> 	write(sfd, "s /dev/sdb1"); // note I'm ignoring write's length arg
> 	write(sfd, "o noatime");
> 	write(sfd, "o acl");
> 	write(sfd, "o user_attr");
> 	write(sfd, "o iversion");
> 	write(sfd, "o ");
> 	write(sfd, "r /my/container"); // root inside the fs
> 	write(sfd, "x create"); // create the superblock

A minor detail but ... the "r" operation mentioned above is not actually
implemented in this system call.

jon