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POCython - convert wide string (wchar_t *) to Python 3 unicode object
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copied!<p>I'm wrapping a C library to Pyhon 3 using Cython and i'm looking for a way of converting wchar_t string to python object which i want to return from a function. There's an answer in <a href="https://stackoverflow.com/questions/12778832/how-to-wrap-a-c-function-whose-parameter-is-wchar-t-pointer-with-cython">this question</a>, but it involves encoding the string as multibyte str, and decoding it back to unicode. I hope for more straightforward solution. I tried using <a href="http://docs.python.org/3.3/c-api/unicode.html#PyUnicode_FromWideChar" rel="nofollow noreferrer">PyUnicode_FromWideChar</a> from Python C API, but i'm getting a segfault. Here's my .pyx code:</p> <pre><code>from cpython.ref cimport PyObject from libc.stddef cimport wchar_t cdef extern from "Python.h": PyObject* PyUnicode_FromWideChar(wchar_t *w, Py_ssize_t size) cdef extern from "../../src/my_c_lib.h": wchar_t * myObjToStr(wchar_t * result, size_t size, myObj * obj) cdef class MyClass: cdef myObj * ptr ... def to_str(self): cdef wchar_t buf[64] cdef wchar_t * result = myObjToStr(buf, 64, self.ptr) if result is NULL: raise Exception("Error converting object to string.") cdef PyObject * pystr = PyUnicode_FromWideChar(result, 64) return <object>pystr </code></pre> <p><code>result</code> is actually the pointer to <code>buf</code>. What's wrong with this? Is there another way without encoding/decoding?</p> <p>Edit: I found that <code>PyUnicode_FromWideChar()</code> returns NULL, but why? I checked, that <code>result</code> is a valid wchar_t * string.</p>

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