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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 26 Jan 2021 10:49:11 -0800
Message-ID: <CAHk-=wh9BELRf-huvVa2vQpFqKiqLHwqu9Wc6RHTvCcVS=5SDA@mail.gmail.com>
Subject: Re: Splicing to/from a tty
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Johannes Berg <johannes@sipsolutions.net>,
        Christoph Hellwig <hch@lst.de>,
        Oliver Giles <ohw.giles@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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On Mon, Jan 25, 2021 at 10:07 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> On Sun, Jan 24, 2021 at 11:11:42AM -0800, Linus Torvalds wrote:
> >
> > I agree that it would be better fixed by just having sendfile()
> > basically turn into splice() for the pipe target case, but I haven't
> > seen any patches from you, so I assume it wasn't 100% trivial.
>
> Just to make clear - sendfile() regular-to-pipe is *not* the same
> issue as splice to/from tty.

That's not what I meant.

sendfile() to a pipe is basically the same thing as splice() to a pipe.

Except I think it might have different looping behavior. And as you
noted earlier, the error returns may be randomly different.

             Linus