HAL and scanners

Étienne Bersac bersace03 at laposte.net
Sat Dec 30 10:41:08 PST 2006


Hi,

> The important thing to remember about HAL is that it's primarily used 
> for device enumeration.  The acronym "hardware abstraction layer" is 
> mostly a misnomer.

Ok.

> It's still the responsibility of applications to use the SANE, or 
> gnome-scan, or whatever APIs to do the scanning.  HAL hopefully removes 
> the necessity on the user to have to provide information about their 
> scanner, the device node (if people have to provide /dev/bleh, we lose), 
> etc.

So the problem is how the app can give to SANE an udi ?

> So it sounds to me like you'd want to keep the glibish API, but have it 
> be a pretty simple wrapper, with the widgets and plugins.

The GLib-ish API is not that simple :). It provide GObject API similar
to GtkPrint (i intend to make it more consistent to GtkPrint API). All i
want is to drop the sane_get_devices call and replace it with a hal
call. But, hal must provide me at least all information provided in
Sane_Device_Descriptor struct (see
http://sane.alioth.debian.org/html/doc011.html#s4.2.8 or better:
http://sane.alioth.debian.org/sane2/0.08/doc011.html#s4.2.8 ). Or i wont
be able to use that device with hal.

Imho, a good solution should be to provide "scanner.sane.backend" in
HAL, an allow in SANE to use g_strconcat (backend, ":", udi, NULL) as
sane device name (instead of e.g. plustek:libusb:001:002 ).

Étienne.
-- 
> 
> Verso l'Alto !
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