Hi,
I'm getting the no backend detected error (well it did work once but I
couldn't get it work again). This is on Mavericks 10.9.2, libusb-1.0.9,
and pyusb-1.0.b.1. There weren't any obvious install errors. I tried export
PYUSB_DEBUG_LEVEL=debug, but it only seems to output more after calling
usb.core.find() a second time? (and nothing extra from the command line
even setting the file output) Output is below. Listing devices using the
libusb example works fine so I think that's installed right. Any ideas?
Thanks,
Jen
In [1]: import usb
In [2]: usb.core.find()
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
<ipython-input-2-acfe6f4fcfac> in <module>()
----> 1 usb.core.find()
/Library/Python/2.7/site-packages/usb/core.pyc in find(find_all, backend,
custom_match, **args)
862 break
863 else:
--> 864 raise ValueError('No backend available')
865
866 k, v = args.keys(), args.values()
ValueError: No backend available
In [3]: usb.core.find()
---------------------------------------------------------------------------
AttributeError Traceback (most recent call last)
<ipython-input-3-acfe6f4fcfac> in <module>()
----> 1 usb.core.find()
/Library/Python/2.7/site-packages/usb/core.pyc in find(find_all, backend,
custom_match, **args)
870 else:
871 try:
--> 872 return _interop._next(device_iter(k, v))
873 except StopIteration:
874 return None
/Library/Python/2.7/site-packages/usb/_interop.pyc in _next(iter)
58 def _next(iter):
59 try:
---> 60 return next(iter)
61 except NameError:
62 return iter.next()
/Library/Python/2.7/site-packages/usb/core.pyc in device_iter(k, v)
838
839 def device_iter(k, v):
--> 840 for dev in backend.enumerate_devices():
841 d = Device(dev, backend)
842 if _interop._reduce(
/Library/Python/2.7/site-packages/usb/backend/libusb0.pyc in
enumerate_devices(self)
396 @methodtrace(_logger)
397 def enumerate_devices(self):
--> 398 _check(_lib.usb_find_busses())
399 _check(_lib.usb_find_devices())
400 bus = _lib.usb_get_busses()
/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/ctypes/__init__.pyc
in __getattr__(self,
name)
376 if name.startswith('__') and name.endswith('__'):
377 raise AttributeError(name)
--> 378 func = self.__getitem__(name)
379 setattr(self, name, func)
380 return func
/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/ctypes/__init__.pyc
in __getitem__(self,
name_or_ordinal)
381
382 def __getitem__(self, name_or_ordinal):
--> 383 func = self._FuncPtr((name_or_ordinal, self))
384 if not isinstance(name_or_ordinal, (int, long)):
385 func.__name__ = name_or_ordinal
AttributeError: dlsym(RTLD_DEFAULT, usb_find_busses): symbol not found
------------------------------------------------------------------------------
Learn Graph Databases - Download FREE O'Reilly Book
"Graph Databases" is the definitive new guide to graph databases and their
applications. Written by three acclaimed leaders in the field,
this first edition is now available. Download your free book today!
http://p.sf.net/sfu/13534_NeoTech
_______________________________________________
pyusb-users mailing list
pyusb-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/pyusb-users
