From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Date: Wed, 04 Jan 2006 17:54:48 +0000 Subject: Re: [2.6 patch] schedule obsolete OSS drivers for removal Message-Id: List-Id: References: <20060103203732.GF5262@irc.pl> <9a8748490601031256x916bddav794fecdcf263fb55@mail.gmail.com> <20060103215654.GH3831@stusta.de> <20060103221314.GB23175@irc.pl> <20060103231009.GI3831@stusta.de> <20060104000344.GJ3831@stusta.de> <20060104010123.GK3831@stusta.de> <20060104113726.3bd7a649@mango.fruits.de> In-Reply-To: <20060104113726.3bd7a649@mango.fruits.de> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: mista.tapas@gmx.net Cc: Adrian Bunk , Jesper Juhl , Olivier Galibert , Alistair John Strachan , Jan Engelhardt , Andi Kleen , perex@suse.cz, alsa-devel@alsa-project.org, James@superbug.demon.co.uk, sailer@ife.ee.ethz.ch, linux-sound@vger.kernel.org, zab@zabbo.net, kyle@parisc-linux.org, parisc-linux@lists.parisc-linux.org, jgarzik@pobox.com, Thorsten Knabe , zwane@commfireservices.com, zaitcev@yahoo.com, linux-kernel@vger.kernel.org At Wed, 4 Jan 2006 11:37:26 +0100, tapas wrote: > > -- ALSA's default open mode is "blocking". But the ALSA API uses the > term blocking in two meanings and throws them together into the open > mode of a pcm device. Normally on device files, blocking access means a > read()/write() returns, when there's data which has actually been > read/written to the device. nonblocking access means, read()/write() > return immediately. In ALSA blocking mode means above _plus_ that the > open call will only immediately return (in case of contention) when the > previous user of the audio device has given it up. > > The combination of the last two is deadly :) It leaves users with > nonfunctional sound plus seemingly hanging apps when their soundcard is > not hardware mixing capable. So IMHO, to fix these two issues really is > the most pressing matter of all, but like i said, sadly ALSA devs seem > to disagree (i haven't followed ALSA development that closely lately > though). Note that as of OSS emulation, this is no longer true. The OSS devices are opened as "non-blocking" per default. ALSA native devices are opened as "blocking" just to keep the compatible behavior, though. Takashi