How do I build a python string from a ctype struct?

Question

I\'m using ctypes and I\'ve defined this struct in order to pass parameters

class my_struct(ctypes.Structure):
    _fields_ = [ (\"buffer\", ctypes.c_char * BUFS         


        

Answer 1

I think you need to send a pointer to a C string in your my_struct, and not a C string directly, because C strings are null-terminated. Try to do it like this:

import ctypes

BUFSIZE = 10

class my_struct(ctypes.Structure):
    _fields_ = [ ("buffer", ctypes.POINTER(ctypes.c_char)),
                 ("size", ctypes.c_int )]

cstr = (ctypes.c_char * BUFSIZE)()
proto = my_struct(cstr)