Error using callback in Python

Question

I am developing a dll that should be used in Python. I have a callback function to send my parameters (defined in a separate header):

typedef int(*call_nBest)(

Answer 1

Do you want something like this?

def callbackU(OutList, ConList, nB):
    for i in range(nB):
        print("{}\t{}".format(ConList[i], cast(OutList[i], c_char_p)))
    return 0

From what I understand you're just trying to match the output of your Python callbackU function with your C++ MyCallback function.

Python has a variety of string formatting functionality that can be confusing at first, but pays homage to printf string formatting.

Since OutList has type LP_LP_c_char (pointer to pointer of c_char, vs "NULL terminated char *" c_char_p), we'd best turn it into a native Python data type like so:

def callbackU(OutList, ConList, nB):
    for i in range(nB):
        out_list_item = cast(OutList[i], c_char_p).value
        print("{}\t{}".format(ConList[i], out_list_item))
    return 0