Re: [PATCH v2 3/4]: sendfile: remove flags paramter of do_splice_direct()

[Changli Gao]

On Sun, May 30, 2010 at 8:39 AM, Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> Probably because I copied the code from something that used
> SPLICE_F_NONBLOCK ;-)
>

>From the relay API implementation?

> But userspace passes that flag too. Although, maybe I just don't
> understand the API fully.
>

this flag is a little confusing. It is much like:

flags = fcntl(pipe_fd, F_GETFL);
fcntl(pipe_fd, F_SETFL, flags | O_NONBLOCK);
splice(..pipe_fd..., 0); // without O_NONBLOCK
fcntl(pipe_fd, F_SETFL, falgs);

In fact, setting O_NONBLOCK is the only way of letting splice pipe
operations non-blockable currently. When splicing, splice doesn't
refer to the pipe file's f_flags. :(

-- 
Regardsï
Changli Gao(xiaosuo@xxxxxxxxx)
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