C-extension in Python: Conver wchar string to Python Value

Question

In C-extension of Python, I can use Py_BuildValue() to Conver char string to Python Value like this: Py_BuildValue("s", str). But, if the string is wchar array, the Py_BuildValue("s", str) can not be used.

I think I can use PyUnicode like this:

PyObject* pb=PyUnicode_FromUnicode( (const Py_UNICODE*)(str), wcslen(str) );
PyObject *val = Py_BuildValue("o", pb);

But, it does not work. How can I conver wchar string to Python Value?

Answer 1

I think you don't need to combine PyUnicode_FromUnicode and Py_BuildValue.

The following pb is already a Python unicode object.

PyObject* pb=PyUnicode_FromUnicode( (const Py_UNICODE*)(str), wcslen(str) );

Using Py_BuildValue to process it is redundant, but it's harmless. I think your problem is caused by the incorrect format o. It should be O.

You can also use Py_BuildValue to convert a null-terminated buffer of Unicode (UCS-2 or UCS-4) data to a Python Unicode object.
For example:

const wchar_t *w = L"Hello world!";
PyObject* pb = Py_BuildValue("u", w);

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