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Code Issues Releases Wiki Activity

Remove obsolete FAQ.

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Ezio Melotti 2011-10-23 23:42:51 +03:00
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Doc/faq/extending.rst
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@ -447,34 +447,3 @@ In Python 2.2, you can inherit from built-in classes such as :class:`int`,
The Boost Python Library (BPL, http://www.boost.org/libs/python/doc/index.html) The Boost Python Library (BPL, http://www.boost.org/libs/python/doc/index.html)
provides a way of doing this from C++ (i.e. you can inherit from an extension provides a way of doing this from C++ (i.e. you can inherit from an extension
class written in C++ using the BPL). class written in C++ using the BPL).
When importing module X, why do I get "undefined symbol: PyUnicodeUCS2*"?
-------------------------------------------------------------------------
You are using a version of Python that uses a 4-byte representation for Unicode
characters, but some C extension module you are importing was compiled using a
Python that uses a 2-byte representation for Unicode characters (the default).
If instead the name of the undefined symbol starts with ``PyUnicodeUCS4``, the
problem is the reverse: Python was built using 2-byte Unicode characters, and
the extension module was compiled using a Python with 4-byte Unicode characters.
This can easily occur when using pre-built extension packages. RedHat Linux
7.x, in particular, provided a "python2" binary that is compiled with 4-byte
Unicode. This only causes the link failure if the extension uses any of the
``PyUnicode_*()`` functions. It is also a problem if an extension uses any of
the Unicode-related format specifiers for :c:func:`Py_BuildValue` (or similar) or
parameter specifications for :c:func:`PyArg_ParseTuple`.
You can check the size of the Unicode character a Python interpreter is using by
checking the value of sys.maxunicode:
>>> import sys
>>> if sys.maxunicode > 65535:
... print('UCS4 build')
... else:
... print('UCS2 build')
The only way to solve this problem is to use extension modules compiled with a
Python binary built using the same size for Unicode characters.