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Date: Sun, 14 Oct 2001 19:06:54 -0700 (PDT)
From: Linus Torvalds <torvalds@transmeta.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
cc: "Eric W. Biederman" <ebiederm@xmission.com>,
        Alexander Viro <viro@math.psu.edu>, <linux-kernel@vger.kernel.org>
Subject: Re: [RFC] "Text file busy" when overwriting libraries
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On Mon, 15 Oct 2001, Alan Cox wrote:
>
> > We already can open an exec only file just open("file", 0).
>
> Wrong.

For exact details: there's a magic value, but it's 3.

	open("file", 3)

will open the filename with neither read nor write permissions, but it
will actually _require_ both read- and write- permissions, and it was
historically a way to open a device just for ioctl's.

I don't think anybody actually uses it any more.

		Linus

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