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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 18 Jan 2021 11:46:42 -0800
Message-ID: <CAHk-=wh6HLz_qMam_J=W3X4caBqAGN8P+8c_y+sGFvBaD70K8w@mail.gmail.com>
Subject: Re: Splicing to/from a tty
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@lst.de>,
        Johannes Berg <johannes@sipsolutions.net>,
        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 18, 2021 at 11:35 AM Al Viro <viro@zeniv-ca> wrote:
>
> I'd rather have sendfile(2) do what splice(2) does and handle pipes
> directly.  Let me take a look,,,

It's not technically just the sendfile() thing. Some things do
sendfile "internally" (ie they use do_splice_direct()).

Although maybe they always happen just on non-pipe destinations (ie
file-to-file copy). I didn't check.

But particularly if it can be handled in do_splice_direct(), that
would be a good thing.

             Linus