From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 19 Sep 2001 13:22:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 19 Sep 2001 13:22:09 -0400 Received: from [208.129.208.52] ([208.129.208.52]:57606 "EHLO xmailserver.org") by vger.kernel.org with ESMTP id ; Wed, 19 Sep 2001 13:21:55 -0400 Message-ID: X-Mailer: XFMail 1.5.0 on Linux X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <3BA84367.239FA0B4@distributopia.com> Date: Wed, 19 Sep 2001 10:25:38 -0700 (PDT) From: Davide Libenzi To: "Christopher K. St. John" Subject: Re: [PATCH] /dev/epoll update ... Cc: Dan Kegel , linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 19-Sep-2001 Christopher K. St. John wrote: > Dan Kegel wrote: >> >> I'm getting ready to stress-test /dev/epoll finally. >> In porting my Poller_devpoll.{cc,h} to support /dev/epoll, I noticed >> the following issues: >> > > Another issue to throw into the mix: > > The Banga, Mogul and Druschel[1] paper (which I understand > was the inspiration for the Solaris /dev/poll which was the > inspiration for /dev/epoll?) talks about having the poll > return the current state of new descriptors. As far as I can > tell, /dev/epoll only gives you events on state changes. So, > for example, if you accept() a new socket and add it to the > interest list, you (probably) won't get a POLLIN. That's > not fatal, but it's awkward. Being an event change notification you simply can't add the fd to the "monitor" after you've issued the accept(). The skeleton for /dev/epoll usage is : while (system_call(...) == FAIL) { wait_event(); } - Davide