My study of this language was started today. And while my knowledge base is somewhere between zero and void I already can ask stupid qustions, which were not answered on #python / irc.freenode.net

What python type to use when c++ to python boost::python binding requires 'unsigned char *' parameter?
Code snippet will tell much more:

class test_class : public test_class_base {
	public:
		test_class(const char *path);
		virtual ~test_class();

		virtual void log(const char *msg);
		unsigned char test(unsigned char *ptr) { return *ptr; };
	private:
		std::ofstream *stream;
};

....

	class_ >("test_class", init())
		.def("log", &test_class::log, &test_class_wrap::default_log)
		.def("test", &test_class::test)
	;

I ommitted wrapper class definition, since it is not critical. It works for python-string to c++ 'const char *' transform, but unsigned char pointer fires up an error. I tried both struct.unpack_from("P", array) and array.buffer_info()[0], but python says that they both return 'int' while c++ code expects 'unsigned char *':

id = array('B')
for x in xrange(0, 20) :
	id.append(x)

s = struct.unpack_from("P", id);
print hex(s[0])

t = test_class("/dev/stderr")
print hex(t.test(s[0]))

error:
[zbr@baccara python]$ ./test.py
0x3020100
Traceback (most recent call last):
  File "./test.py", line 19, in 
    print hex(t.test(s[0]))
Boost.Python.ArgumentError: Python argument types in
    test_class.test(test_class, int)
did not match C++ signature:
    test(test_class {lvalue}, unsigned char*)

Code snippets can be also found at http://paste.pocoo.org/show/239085/.

If no solution will be found, I will refactor elliptics python binding to support new classes for missing types like 'elliptics_id' for 'unsigned char *'.