Re: epoll vs stdin/stdout

["H. Peter Anvin" <hpa@zytor.com>]

Followup to:  <beckj5$e2a$1@news.cistron.nl>
By author:    "Miquel van Smoorenburg" <miquels@cistron.nl>
In newsgroup: linux.dev.kernel
>
> In article <20030707200315.GA10939@mail.jlokier.co.uk>,
> Jamie Lokier  <jamie@shareable.org> wrote:
> >Unfortunately I cannot think of a way for a process to know, in
> >general, whether two fds that it is passed correspond to the same file
> >*.  Well, apart from trying epoll on it and seeing what happens :/
> 
> fstat() and compare st_dev and st_ino
> 

That doesn't show if they share the same file *.  Two fd's can be open
to the same file or other object without sharing the same file *.

Seriously, this is not something userspace should have to worry
about.  The interface should handle it, otherwise it's broken.

	-hpa
-- 
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