Ubuntu
python-imaging package

networked scanners not working with python2.4 sane

Bug #88059 reported by jamest on 2007-02-26

Affects		Status	Importance	Assigned to	Milestone
	python-imaging (Ubuntu)	Fix Released	Undecided	Matthias Klose

Bug Description

Binary package hint: python-imaging-sane

The python2.4 sane module doesn't appear to work with networked scanners under edgy.
Python2.5 appears to be fine.

An attempt from 2.4 to access a scanner.

jamest@floyd:~$ python
Python 2.4.4c1 (#2, Oct 11 2006, 21:51:02)
[GCC 4.1.2 20060928 (prerelease) (Ubuntu 4.1.1-13ubuntu5)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sane
>>> print 'SANE version:', sane.init()
SANE version: (16777234, 1, 0, 18)
>>> scanner=sane.open('net:scanner.ajrs.com:avision:libusb:001:002')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/lib/python2.4/site-packages/sane.py", line 260, in open
    new=SaneDev(devname)
  File "/usr/lib/python2.4/site-packages/sane.py", line 118, in __init__
    d['sane_signature'] = self._getSaneSignature(devname)
  File "/usr/lib/python2.4/site-packages/sane.py", line 126, in _getSaneSignature
    raise RuntimeError('no scanner available')
RuntimeError: no scanner available
>>>

Now the same attempt from python2.5

jamest@floyd:~$ python2.5
Python 2.5 (r25:51908, Oct 6 2006, 15:22:41)
[GCC 4.1.2 20060928 (prerelease) (Ubuntu 4.1.1-13ubuntu4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sane
>>> print 'SANE version:', sane.init()
SANE version: (16777234, 1, 0, 18)
>>> scanner=sane.open('net:scanner.ajrs.com:avision:libusb:001:002')
>>> print 'SaneDev object=', scanner
SaneDev object= <sane.SaneDev instance at 0xb7d1356c>
>>>

Revision history for this message

Jason Parekh (jasonparekh) wrote on 2007-04-04:

Sets an initial value for the variable local_only Edit (341 bytes, text/plain)

Seems to reappear in Feisty (never tested the problem under Edgy myself).

Attached is a fix. The problem is there isn't an initial value for the optional variable local_only in PySane_get_devices(). So, when sane.get_devices() is called without an argument (like it is through sane.open()), the value of local_only will be arbitrary leading to local only operation with high probability.

Jason Parekh

Revision history for this message

Matthias Klose (doko) wrote on 2007-04-04:

fixed in python-imaging_1.1.6-0ubuntu3

Changed in python-imaging:
assignee:	nobody → doko
status:	Unconfirmed → Fix Released

Revision history for this message

Ulf Renman (ulf-renman) wrote on 2009-02-11:

Has this been broken again? I have a similar problem but my scanner is not networked, but local. Im on Ubuntu Intrepid Ibex.

Some output from my system:
ulf@hovermo:~(0)$ groups
ulf adm lp dialout cdrom plugdev scanner lpadmin admin sambashare
ulf@hovermo:~(0)$ cat /proc/version
Linux version 2.6.27-11-generic (buildd@rothera) (gcc version 4.3.2 (Ubuntu 4.3.2-1ubuntu11) ) #1 SMP Thu Jan 29 19:24:39 UTC 2009
ulf@hovermo:~(0)$ scanimage -L
device `epkowa:libusb:001:012' is a Epson Perfection V10/V100 flatbed scanner
ulf@hovermo:~(0)$ python
Python 2.5.2 (r252:60911, Oct 5 2008, 19:24:49)
[GCC 4.3.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sane
>>> sane.get_devices()
[]
>>> sane.open('epkowa:libusb:001:012')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.5/site-packages/sane.py", line 288, in open
    new=SaneDev(devname)
  File "/usr/lib/python2.5/site-packages/sane.py", line 143, in __init__
    d['sane_signature'] = self._getSaneSignature(devname)
  File "/usr/lib/python2.5/site-packages/sane.py", line 151, in _getSaneSignature
    raise RuntimeError('no scanner available')
RuntimeError: no scanner available
>>>