[sane-devel] usb connection found, but scanners not identified...

Ilias Miroslav Miroslav.Ilias at umb.sk
Wed Dec 25 10:42:20 UTC 2013

Hi Olaf,

thanks for you hints; here we go:

Now I am with the Epson SX400 scanner/printer. I deativated ppa's of rolf bench's sane-backends, and returned to the default for Ubuntu 13.10 - 1.0.23.

ilias at miro_ilias_desktop:~/.dpkg-query --show libsane
libsane:amd64   1.0.23-0ubuntu3
libsane:i386    1.0.23-0ubuntu3

Strange,  the /etc/sane.d/ directory is empty, there are no conf files. Why ? A reinstalled/repaired the libsane package several times.
ilias at miro_ilias_desktop:~/.ls /etc/sane.d/

The package lists a lot of them:
ilias at miro_ilias_desktop:~/.dpkg-query --listfiles libsane | grep /etc/sane.d

ilias at miro_ilias_desktop:~/.sudo sane-find-scanner
could not fetch string descriptor: Pipe error
could not fetch string descriptor: Pipe error
found USB scanner (vendor=0x0cf3 [ATHEROS], product=0x9271 [USB2.0 WLAN]) at libusb:001:002
could not fetch string descriptor: Pipe error
could not fetch string descriptor: Pipe error

lsusb gives:  Bus 001 Device 002: ID 0cf3:9271 Atheros Communications, Inc. AR9271 802.11n

scanimage -L gives not device.

And the printing with Epson SX400 works fine.



From: Olaf Meeuwissen [olaf.meeuwissen at avasys.jp]
Sent: Wednesday, December 25, 2013 9:38 AM
To: Ilias Miroslav
Cc: sane-devel at lists.alioth.debian.org
Subject: Re: [sane-devel] usb connection found, but scanners not identified...

Ilias Miroslav writes:

> Dear experts,
> maybe you can help me, few days I am struggling with lost access to my
> 2 scanners (Epson SX400 and Cannon MF3010).  I put here some findings,
> https://answers.launchpad.net/ubuntu/+source/sane-backends/+question/240955

Read that and the forum post it references.  No mention about the Epson
SX400 but it looks like you have been "playing" around with a package
from a ppa and maybe even a source build.  Hmm, I'd get rid of all that
first and reinstall the official libsane package.

BTW, what ppa did you use anyway?  Did whoever build the package enable
all the backends you need or just whatever that person needed?

> Shortly, "sudo sane-find-scanner" detects these scanners sitting on
> USB ports, but "sudo scanimage -L" gives no scanner detected.

Please note that sane-find-scanner works independently of whatever is
below /etc/sane.d and whatever backends are installed.

> (Strange that I am getting "could not fetch string descriptor: Pipe
> error", could it be this the cause ?)
> I checked SANE manual, reinstalled packages few times (I am using
> newest ppa for “sane-backends”), searched internet...
> Even when I returned to older (Ubuntu 13.10 default) version of
> “sane-backends”, the Epson SX400, which was working previously, was
> not detected...The same symptoms - scanner is detected as device on
> usb port, but not detected as scanner for real work.

Your lists of configuration files below /etc/sane.d/ look suspiciously
short.  For the Epson SX400, I would expect epson2.conf in there and an
uncommented epson2 entry in dll.conf.  The dll.conf file I would also
expect to be there.

Without these expectations met, I do not expect scanimage -L to find
your scanner.

> What could be wrong ? What commands shall I check ? Seems the problem
> is not in newest “sane-backends”, but elsewhere in the system....

Can you check the version and configuration file content of your libsane
package?  Does that match with what you have on your system?  Does it
include the dll.conf, epson2.conf and expected canon configuration file
(pixma.conf, I think)?

  $ dpkg-query --show libsane
  $ dpkg-query --listfiles libsane | grep /etc/sane.d

Hope this helps,
Olaf Meeuwissen, LPIC-2           FLOSS Engineer -- AVASYS CORPORATION
FSF Associate Member #1962               Help support software freedom

More information about the sane-devel mailing list