'No suitable backend found' error

[clayton craft]

Executing disper with any of the available actions results in the following error: "No suitable backend found"

Examples:
cacraft@cacraft-MOBL ~ $ disper -l
No suitable backend found
cacraft@cacraft-MOBL ~ $ disper -e
No suitable backend found
cacraft@cacraft-MOBL ~ $ disper -p
No suitable backend found
cacraft@cacraft-MOBL ~ $ disper -s
No suitable backend found

Nothing is printed to dmesg (or to syslog for that matter). I am running nvidia-drivers-180.35 x86_64.

cacraft@cacraft-MOBL ~ $ nvidia-settings -q gpus
1 GPU on cacraft-MOBL:0
    [0] cacraft-MOBL:0[gpu:0] (Quadro FX 570M)

cacraft@cacraft-MOBL ~ $ nvidia-settings -q OpenGLVersion
  Attribute 'OpenGLVersion' (cacraft-MOBL:0.0): 2.1 Mesa 7.3-rc2

cacraft@cacraft-MOBL ~ $ grep -i "X.Org X Server" /var/log/Xorg.0.log
X.Org X Server 1.6.0

cacraft@cacraft-MOBL ~ $ xrandr -v
Server reports RandR version 1.3

cacraft@cacraft-MOBL ~ $ uname -a
Linux cacraft-MOBL 2.6.28 #21 SMP PREEMPT Tue Feb 17 10:01:15 PST 2009 x86_64 Intel(R) Core(TM)2 Duo CPU T9500 @ 2.60GHz GenuineIntel GNU/Linux

[wvengen (wvengen)]

Thanks for your bug report. You've probably run into a serious bug in the nVidia backend. Could you please try the following at a command prompt and report what the output is exactly?
  cd /usr/share/disper/src
  python -c 'from nvidia import *; NVidiaControl()'

[clayton craft (craftyguy)]

I don't get any output at all...

cacraft@cacraft-MOBL /usr/src/software/disper/src $ python -c 'from nvidia import *; NVidiaControl()'
cacraft@cacraft-MOBL /usr/src/software/disper/src $

[wvengen (wvengen)]

That's good. I should have asked to try this as well
  cd /usr/share/disper/src
  python -c 'from switcher.swnvidia import *; NVidiaSwitcher()'
I suspect that does give some output.

[clayton craft (craftyguy)]

Here's the output:

cacraft@cacraft-MOBL /usr/share/disper/src $ python -c 'from switcher.swnvidia import *; NVidiaSwitcher()'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "switcher/swnvidia.py", line 19, in <module>
    import xrandr
  File "xrandr/__init__.py", line 41, in <module>
    from ctypes import *
  File "/usr/lib64/python2.5/ctypes/__init__.py", line 20, in <module>
    raise Exception, ("Version number mismatch", __version__, _ctypes_version)
Exception: ('Version number mismatch', '1.0.3', '1.0.2')

[wvengen (wvengen)]

Thanks, that narrows the problem to the python xrandr bindings and/or ctypes. There may be a problem with your python ctypes installation. It looks like a bug #285411; could you please verify that it is the case by running the following:
   grep ^__version__ /usr/share/pyshared/ctypes/__init__.py
   strings /usr/lib/python*/lib-dynload/_ctypes.so | grep 1\.\0\.
if these numbers are different it is the culprit.

[wvengen (wvengen)]

Still the problem doesn't occur here although these version numbers are different with me. The output of the following commands might help as well
  python -v -c 'import ctypes'
If that doesn't fail, please try
   cd /usr/share/disper/src
  python -v -c 'import xrandr'

[clayton craft (craftyguy)]

They are different:

cacraft-MOBL disper # grep ^__version__ /usr/lib64/python2.5/ctypes/__init__.py
__version__ = "1.0.3"
cacraft-MOBL disper # strings /usr/lib64/python2.5/site-packages/_ctypes.so | grep 1\.\0\.
1.0.2

cacraft-MOBL disper # python -v -c 'import ctypes'
# installing zipimport hook
import zipimport # builtin
# installed zipimport hook
# /usr/lib64/python2.5/site.pyc matches /usr/lib64/python2.5/site.py
import site # precompiled from /usr/lib64/python2.5/site.pyc
# /usr/lib64/python2.5/os.pyc matches /usr/lib64/python2.5/os.py
import os # precompiled from /usr/lib64/python2.5/os.pyc
import errno # builtin
import posix # builtin
# /usr/lib64/python2.5/posixpath.pyc matches /usr/lib64/python2.5/posixpath.py
import posixpath # precompiled from /usr/lib64/python2.5/posixpath.pyc
# /usr/lib64/python2.5/stat.pyc matches /usr/lib64/python2.5/stat.py
import stat # precompiled from /usr/lib64/python2.5/stat.pyc
# /usr/lib64/python2.5/UserDict.pyc matches /usr/lib64/python2.5/UserDict.py
import UserDict # precompiled from /usr/lib64/python2.5/UserDict.pyc
# /usr/lib64/python2.5/copy_reg.pyc matches /usr/lib64/python2.5/copy_reg.py
import copy_reg # precompiled from /usr/lib64/python2.5/copy_reg.pyc
# /usr/lib64/python2.5/types.pyc matches /usr/lib64/python2.5/types.py
import types # precompiled from /usr/lib64/python2.5/types.pyc
import _types # builtin
# /usr/lib64/python2.5/warnings.pyc matches /usr/lib64/python2.5/warnings.py
import warnings # precompiled from /usr/lib64/python2.5/warnings.pyc
# /usr/lib64/python2.5/linecache.pyc matches /usr/lib64/python2.5/linecache.py
import linecache # precompiled from /usr/lib64/python2.5/linecache.pyc
import encodings # directory /usr/lib64/python2.5/encodings
# /usr/lib64/python2.5/encodings/__init__.pyc matches /usr/lib64/python2.5/encodings/__init__.py
import encodings # precompiled from /usr/lib64/python2.5/encodings/__init__.pyc
# /usr/lib64/python2.5/codecs.pyc matches /usr/lib64/python2.5/codecs.py
import codecs # precompiled from /usr/lib64/python2.5/codecs.pyc
import _codecs # builtin
# /usr/lib64/python2.5/encodings/aliases.pyc matches /usr/lib64/python2.5/encodings/aliases.py
import encodings.aliases # precompiled from /usr/lib64/python2.5/encodings/aliases.pyc
# /usr/lib64/python2.5/encodings/utf_8.pyc matches /usr/lib64/python2.5/encodings/utf_8.py
import encodings.utf_8 # precompiled from /usr/lib64/python2.5/encodings/utf_8.pyc
Python 2.5.2 (r252:60911, Nov 25 2008, 10:20:37)
[GCC Intel(R) C++ gcc 4.1 mode] on linux2
Type "help", "copyright", "credits" or "license" for more information.
import ctypes # directory /usr/lib64/python2.5/ctypes
# /usr/lib64/python2.5/ctypes/__init__.pyc matches /usr/lib64/python2.5/ctypes/__init__.py
import ctypes # precompiled from /usr/lib64/python2.5/ctypes/__init__.pyc
dlopen("/usr/lib64/python2.5/site-packages/_ctypes.so", 2);
import _ctypes # dynamically loaded from /usr/lib64/python2.5/site-packages/_ctypes.so
# /usr/lib64/python2.5/struct.pyc matches /usr/lib64/python2.5/struct.py
import struct # precompiled from /usr/lib64/python2.5/struct.pyc
dlopen("/usr/lib64/python2.5/lib-dynload/_struct.so", 2);
import _struct # dynamically loaded from...

[wvengen (wvengen)]

As a workaround I'll create an XRandR fallback method that calls the xrandr binary instead of using ctypes bindings.