Subject: Re: kqueue, NOTE_EOF
To: None <marius@monkey.org>
From: Jaromir Dolecek <jdolecek@NetBSD.org>
List: tech-kern
Date: 11/12/2003 09:58:15
marius aamodt eriksen wrote:
> hi - 
> 
> in order to be able to preserve consistent semantics across poll,
> select, and kqueue (EVFILT_READ), i propose the following change: on
> EVFILT_READ, add an fflag NOTE_EOF which will return when the file
> pointer *is* at the end of the file (effectively always returning on
> EVFILT_READ, but setting the NOTE_EOF flag when it is at the end).
> 
> specifically, this allows libevent[1] to behave consistently across
> underlying polling infrastructures (this has become a practical
> issue).

I'm not sure I understand what is the exact issue.
 
Why would this be necessary or what does this exactly solve? AFAIK
poll() doesn't set any flags in this case neither, so I don't
see how this is inconsistent.

BTW, shouldn't the EOF flag be cleared when the file is extended?

Jaromir
-- 
Jaromir Dolecek <jdolecek@NetBSD.org>            http://www.NetBSD.cz/
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