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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 20 Jan 2021 19:38:38 -0800
Message-ID: <CAHk-=whqZbEPt2WC6WRWrMNPqaTsx99dp74vB6FQfM4aO6biQQ@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 Wed, Jan 20, 2021 at 5:45 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> splice() triggers an error for seekable destination with O_APPEND and
> with NULL off_out.

Ok, that's just broken.

> Same for splice() to socket with
>         fcntl(sock_fd, F_SETFL, O_APPEND);
> done first.

Same.

As long as you don't pass a position pointer, I think both should just work.

Not that I imagine it matters for a lot of people..

              Linus

           Linus