[pulseaudio-discuss] Accessing audio as root

[Bill Cox]

On Thu, Dec 24, 2009 at 11:29 AM, Lennart Poettering
<lennart at poettering.net> wrote:
> On Wed, 23.12.09 15:26, Halim Sahin (halim.sahin at freenet.de) wrote:
>
>>
>> Hi Col,
>> 1. I gave you some examples what doesn't work as expected.
>> How should I run my text-to-speech server before login to have
>> audiooutput for reading the login screen?
>
> On Fedora at least the screenreader runs as normal process in the gdm
> pseudo-session which also happens to run a PA instance. So everything
> should be fine here, and I am quite sure this is not only done on
> Fedora this way but all other distributions that use a current version
> of gdm.

Lennart, let me explain how blind people use Linux.  There are TWO
applications in common use - Orca and Speakup.  Actually, there's a
third - emacspeak, but let's not go there, yet.  Orca is the screen
reader that you are talking about.  It runs as user, and can be made
to work well with PulseAudio.  I've personally helped in that effort
(I wrote a new pulseaudio driver for it).  The other critical
application is Speakup.  It runs as a kernel module and speaks every
bit of console output during the boot process.  Many blind people rely
heavily on Speakup, and only use Orca for websites that require
Firefox to read.

>> 2. Running daemons worked well under alsa (see my previous post).
>> I am using every day this setup.
>
> Running PA doesn't mean ALSA is out of the game. PA builds on ALSA and
> as such everything you could do with ALSA before stays available with
> PA too.
>
> However input output deamons should definitely be part of the user
> session. That is true for PA itself AND any kind of speech daemon and suchlike.

Output deamons do belong in the user session, but not all speech
deamons do.  Speakup, in particular, is a kernel module.  It's job is
speaking all console output to the user.  The blind don't give a hoot
how we get speach from /dev/speakup_soft to the sound card.  It just
has to happen.  Today, on every pulseaudio enabled system I know of,
this does not work properly.  I tried setting speakup to use alsa, and
it works, right up until pulseaudio for gdm starts.  After that,
speakup is mute.  Is there any way for pulseaudio to share the sound
card with speakup/alsa?

Bill