[wellylug] Scanner permissions

[Rob van der Linde]

Oops, found a small bug in the openpsfc software.

I scanned an image using the default detected device. I didn't write a
driver for my scanner just yet, but it scanned anyway using whatever
default driver.

It scanned a tiff and provided a download link to the file

http://192.168.0.3/openpsfc/tmp/scan-2008-09-15-200954.tiff

which got me a 404

I looked in the tmp folder and it really was:

scan-8d382ddfa01f8f99380f6d0a3ff8f834-tiff.1221466168

... the file was also 0 bytes however.

On Mon, 2008-09-15 at 20:05 +1200, Rob van der Linde wrote:
> Thanks, that works. Now to make a driver for openpsfc :)
> 
> On Mon, 2008-09-15 at 19:48 +1200, Jethro Carr wrote:
> > On Mon, 2008-09-15 at 19:40 +1200, Rob van der Linde wrote:
> > > I have a Canon USB scanner which is supported by Linux (I can run it no
> > > problem on Ubuntu 8.04 desktop), that I want to get running on Ubuntu
> > > 8.04 server. When I enter:
> > > 
> > > scanimage -L
> > > 
> > > Nothing shows, however:
> > > 
> > > sudo scanimage -L
> > > 
> > > Comes up with the following:
> > > 
> > > device `plustek:libusb:002:003' is a Canon CanoScan N1240U/LiDE30
> > > flatbed scanner
> > > 
> > > I also ran sane-find-scanner which sees the scanner, it says you may
> > > need to adjust the permissions for scanimage -L to see it. I think that
> > > is is why it is only showing when I run that command as root.
> > > 
> > > I want to be able to use the scanner as the user www-data, so I can run
> > > Jethro's openpsfc software. Any ideas how I should do this?
> > 
> > hi Rob,
> > 
> > I believe it works with your GUI because HAL/GNOME/KDE does some funky
> > stuff to give the user access to the scanner device.
> > 
> > To make it work on a server, I tend to fix it by giving the scanimage
> > command permissions to run as root when executed by any user. Eg:
> > chmod +s /usr/bin/scanimage
> > 
> > There are other ways too, such as setting up sudo access, but the chmod
> > method is easiest.
> > 
> > There may be a better way to give non-root users access to scanners, but
> > I'm not aware of how. (if you know, please do enlighten me! :-)
> > 
> > The problem is that usb scanners don't create device files, so you can't
> > set permissions on them that way, it's all done using kernel APIs.
> > 
> > regards,
> > jethro
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