From mboxrd@z Thu Jan 1 00:00:00 1970 From: ludo@gnu.org (Ludovic =?utf-8?Q?Court=C3=A8s?=) Subject: PulseAudio & ALSA Date: Sun, 17 Jan 2016 21:30:01 +0100 Message-ID: <874mec6jau.fsf_-_@gnu.org> References: <87h9ih4l8n.fsf@gnu.org> <874megs2w4.fsf@gnu.org> <87twmcur0y.fsf@elephly.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:51555) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aKtxg-00024b-62 for guix-devel@gnu.org; Sun, 17 Jan 2016 15:30:09 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aKtxc-0005j3-5e for guix-devel@gnu.org; Sun, 17 Jan 2016 15:30:08 -0500 In-Reply-To: <87twmcur0y.fsf@elephly.net> (Ricardo Wurmus's message of "Sun, 17 Jan 2016 17:09:17 +0100") List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org Sender: guix-devel-bounces+gcggd-guix-devel=m.gmane.org@gnu.org To: Ricardo Wurmus Cc: guix-devel@gnu.org Ricardo Wurmus skribis: > Ludovic Court=C3=A8s writes: > >> Ricardo Wurmus skribis: >> >>> I=E2=80=99m not using pulseaudio; for me it=E2=80=99s just ALSA for reg= ular software + >>> JACK for =E2=80=9Cprofessional=E2=80=9D audio where sync and timing mat= ters. >> >> That=E2=80=99s what I expected. ;-) >> >>> I=E2=80=99m not very knowledgeable about pulseaudio, unfortunately. As >>> pulseaudio can manage audio streams using various different backends >>> from pulseaudio-agnostic software, what really is to be gained by adding >>> pulseaudio to the inputs? AFAIK using pulseaudio directly is not much >>> different from using ALSA and configuring pulseaudio to manage this >>> stream. >> >> As you note, the main difference is configuration. For ALSA-lib to use >> PulseAudio, one has to drop the relevant ~/.asoundrc, but it seems that >> it does not always work properly. >> >> For instance, my ~/.asoundrc reads this: >> >> --8<---------------cut here---------------start------------->8--- >> # FIXME: alsamixer & co. from alsa-utils don't support it. >> >> pcm.!default { >> type pulse >> } >> >> # ctl.!default { >> # type pulse >> # } >> --8<---------------cut here---------------end--------------->8--- >> >> I don=E2=80=99t recall the details of the FIXME and the commented-out pa= rt, >> though. >> >> For GuixSD I think it would be best if everything would automatically go >> through PulseAudio, without the user having to configure obscure things. > > Couldn=E2=80=99t we then just install the appropriate /etc/asound.conf (m= aybe > with a =E2=80=9Cpulseaudio-alsa=E2=80=9D service)? Users could still ove= rwrite it by > disabling the service or with =E2=80=9C~/.asoundrc=E2=80=9D. > > A similar configuration is provided on Arch by the =E2=80=9Cpulseaudio-al= sa=E2=80=9D > package, which should be sufficient to route all ALSA audio streams > through Pulseaudio. Sounds like a good idea. > Wouldn=E2=80=99t that be a better solution than to add the pulseaudio pac= kage to > the inputs wherever possible? Dunno. It seems to me that applications that are PA-aware can have better integration, like have their name shown in pavucontrol and similar interfaces, which is quite useful. There are also technical complications: alsa-lib must be able to find its PulseAudio plug-in (currently we don=E2=80=99t build it since alsa-lib = would depend on PulseAudio), and it must be one that can actually be dlopened by every process out there (linked against the same libc, etc.) Thanks, Ludo=E2=80=99.