# Generic Feedback Renderer

This xAAL device is a so-called user feedback renderer. It waits for an
Inform request on the xAAL bus, then calls a third-party appplication able
to inform the user in a mean or in another. The Inform requests contain a
message and a message-level indicator.


## API of third-party inform-app
Third-party inform appplications are called with the message-level indicator
passed as the only argument in command-line.  The content of the message is
provided in the standard input.  The inform-app should set its return status
as follow: "0" if the inform-app is not capable to manage user
acknowledgement, "1" if the user does acknowledge the message, "2" if the
user does discard the message, any value otherwise.

As an example one proposes 'via_upnpav.sh'
This shell-script arranges the message-text and the message-level indicator
into an svg picutre (see template_*.svg), convert it to jpeg, then push the
jpeg on UPnP-AV rederers. It returns "0".

It depends on: par, sed, inkscape, convert (ImageMagic), and uav-play
<http://uav-play.sourceforge.net/>