[pulseaudio-discuss] Accessing audio as root
tanuk at iki.fi
Thu Nov 26 22:25:57 PST 2009
pe, 2009-11-27 kello 13:08 +0800, Markus Rechberger kirjoitti:
> It works when the user is logged in or not.
> The device supports TV (+Audio), and just simple FM Radio.
> It is possible to remotely access this device (when configured to do so).
> We're about to release a webfrontend for it so you can tune FM radio
> through a website in your homenetwork (the network configuration needs
> to be enabled explicitly by the user).
These are my thoughts based on this description (they may not make sense
if there are additional details that make things more complicated):
The product should provide kernel drivers that create a few devices: for
digital TV you provide a DVB device, for FM radio you provide an ALSA
capture device, and if the device also does analog TV, I'm not sure how
that is usually handled - is it a v4l device for video and an ALSA
capture device for sound?
You apparently want to make sure that there are easy ways to actually
use those devices, so you write some playback software that utilizes the
standard DVB, v4l and ALSA interfaces that your kernel driver has
provided. The user is free to use any other software instead of yours,
thanks to the standard hardware interfaces. Your playback software
shouldn't be tied in any way to your hardware, except for special
hardware features that can't be exposed in a standard way (or if you
really just don't want to make the software interoperable with other
Let's consider local (non-networked) use first. In this case I don't see
why your software should run as root. Provide a normal application that
runs under the user that starts it.
In the networked case your software needs to act as a server, and
servers often are not associated with a user session. Here running as
root makes sense, except that it doesn't - please run your server under
a special-purpose user for security reasons. Anyway, here you're going
to run into problems with PulseAudio. I think that reconfiguring
PulseAudio to run in the system-wide mode makes sense, after notifying
the user and offering a way to restore the configuration (I hope this is
That's what I think, I'm not sure if it helps any...
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