Subject: Re: bug#42175: "pulseaudio? #f" setting does not prevent pulseaudio from autostarting
From: Maxim Cournoyer <[email-masked]>
To: Leo Prikler <[email-masked]>
Cc: [email-masked], [email-masked]
Date: Mon, 31 Jan 2022 21:27:59 -0500
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello,

Leo Prikler <[email-masked]> writes:

> I don't think pulseaudio autostarting is governed by alsa.  There are
> two options you can try.
>
> 1. disable autospawning through configuration.  For that, try setting
> the client-conf field of the pulseaudio-configuration to 
>   '((autospawn . no))
> 2. Removing the pulseaudio package from gnome and anywhere else it
> might be propagated.  (I don't think it is propagated in other
> services).

Indeed, if you look at (gnu services sound), you'll see that what
pulseaudio? #t does (the default) is to add this to ALSA's asound.conf
file:

--8<---------------cut here---------------start------------->8---
`("# Use PulseAudio by default
pcm_type.pulse {
  lib \"" ,#~(string-append #$alsa-plugins:pulseaudio
                            "/lib/alsa-lib/libasound_module_pcm_pulse.so") "\"
}

ctl_type.pulse {
  lib \"" ,#~(string-append #$alsa-plugins:pulseaudio
                            "/lib/alsa-lib/libasound_module_ctl_pulse.so") "\"
}

pcm.!default {
  type pulse
  fallback \"sysdefault\"
  hint {
    show on
    description \"Default ALSA Output (currently PulseAudio Sound Server)\"
  }
}

ctl.!default {
  type pulse
  fallback \"sysdefault\"
}\n\n"
--8<---------------cut here---------------end--------------->8---

This configures ALSA applications to use pulseaudio as its default
output.  Many non-ALSA applications will attempt to use pulseaudio and
the configuration of it being allowed to autostart or not is to be made
at the level of pulseaudio-service-type, as pointed out in Liliana's
reply (thanks!).

Closing,

Maxim