From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.91] helo=mail.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1FKNDq-0003rk-MB for user-mode-linux-devel@lists.sourceforge.net; Fri, 17 Mar 2006 14:15:02 -0800 Received: from smtp008.mail.ukl.yahoo.com ([217.12.11.62]) by mail.sourceforge.net with smtp (Exim 4.44) id 1FKNDn-0006PL-Lx for user-mode-linux-devel@lists.sourceforge.net; Fri, 17 Mar 2006 14:15:02 -0800 From: Blaisorblade Subject: Re: [uml-devel] Occasional hang starting up. References: <200603111301.42195.rob@landley.net> <200603172036.59218.blaisorblade@yahoo.it> <20060317182722.B8529@almesberger.net> In-Reply-To: <20060317182722.B8529@almesberger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200603172314.47124.blaisorblade@yahoo.it> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Fri, 17 Mar 2006 23:14:46 +0100 To: Werner Almesberger Cc: user-mode-linux-devel@lists.sourceforge.net, Jeff Dike , Rob Landley On Friday 17 March 2006 22:27, Werner Almesberger wrote: > Blaisorblade wrote: > > 1) I'll try to fix poll(2) to return -EINVAL. Dunno whether anyone will > > say "no, the app is stupid, it deserves no error", but hope not (with > > "try" I refer to this). Attached patch should do this. > > I think the behaviour of "poll" with nfds = 0 is correct as it is. > At least POSIX doesn't say anything to the extent that "nfds" > couldn't be zero: > http://www.opengroup.org/onlinepubs/009695399/functions/poll.html I don't think that "hanging" is a correct behaviour anyway... unless the application *wanted* to wait for a signal, but this is a clumsy way to do this (I don't think there's any difference from pause()). > Furthermore, this is one of several ways to implement a "sleep" > function with sub-second granularity > , so existing applications > may already depend on "poll" accepting nfds = 0. (Of course, > they would probably be better off using "nanosleep".) This is a very smart note, however usleep(3) exists since 4.3 BSD so this is a bit unlikely; however you're surely right on this. > > 2) write_sigio_thread should do a "down" on a semaphore/mutex and the > > first update_thread should "up" it. > > Yup :-) > > Thanks, > - Werner -- Inform me of my mistakes, so I can keep imitating Homer Simpson's "Doh!". Paolo Giarrusso, aka Blaisorblade (Skype ID "PaoloGiarrusso", ICQ 215621894) http://www.user-mode-linux.org/~blaisorblade ___________________________________ Yahoo! Mail: gratis 1GB per i messaggi e allegati da 10MB http://mail.yahoo.it ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642 _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel