[sane-devel] SANE standard details

[Henning Meier-Geinitz]

Hi,

On Thu, Jan 17, 2002 at 10:34:56PM -0600, Peter Fales wrote:
> I'm also trying to do exactly that, but I think xscanimage doesn't handle it
> quite right.     My camera backends have an "image number" selection which 
> is constrained from 1 to the number of images in the camera.  If I delete
> one of the images, the range is decremented.  I set SANE_INFO_RELOAD_OPTIONS,
> during the "scan"

How can you set SANE_INFO_RELOAD_OPTIONS during the scan? You can only do this
in sane_control_option as far as I see.

> but I've observed the following:
> 
> - The image range slider is not updated at the termination of the scan 
>

I think xscanimage doesn't automaticaly update all the options after a scan.
 
> - If the first thing I do after the scan is click on the image number slider,
>   xscanimage aborts with a memory fault

Oops. It probably trys to access the option_descriptor. Did you malloc a new
one? The option_descriptor must stay valid until sane_close (or a reload).
 
> - If I click on something else like a checkbox, then the slider range also
>   gets updated.

Maybe the checkbox set "SANE_INFO_RELOAD_OPTIONS"?

Maybe it makes sense to reload all options after the scan automatically. Does
xsane do this?

Bye,
  Henning