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Date: Sun, 13 Jul 2003 19:43:12 -0700 (PDT)
From: Davide Libenzi <davidel@xmailserver.org>
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To: Jamie Lokier <jamie@shareable.org>
cc: "David S. Miller" <davem@redhat.com>, Eric Varsanyi <e0206@foo21.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       kuznet@ms2.inr.ac.ru
Subject: Re: POLLRDONCE optimisation for epoll users (was: epoll and half
 closed TCP connections)
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On Sun, 13 Jul 2003, Davide Libenzi wrote:

> void my_process_read(my_data *d, unsigned int events) {
> 	int n, s;
>
> 	do {
> 		s = d->buffer_size - d->in_buffer;
> 		if ((n = read(d->fd, d->buffer + d->in_buffer, s)) > 0) {
> 			process_partial_buffer(d, s);
> 			d->in_buffer += s;
> 		}
> 	} while (n == s);
> 	if (s == -1 && errno != EAGAIN) {
> 		handle_read_error(d);
> 		return;
> 	}
> 	if (events & EPOLLRDHUP) {
> 		d->flags |= HANGUP;
> 		schedule_removal(d);
> 	}
> }

Ouch, this is obviously :

void my_process_read(my_data *d, unsigned int events) {
      int n, s;

      do {
		s = d->buffer_size - d->in_buffer;
		if ((n = read(d->fd, d->buffer + d->in_buffer, s)) > 0) {
			process_partial_buffer(d, n);
			d->in_buffer += n;
		}
	} while (n == s);
	if (n == -1 && errno != EAGAIN) {
		handle_read_error(d);
		return;
	}
	if (events & EPOLLRDHUP) {
		d->flags |= HANGUP;
		schedule_removal(d);
	}
}



- Davide