Re: ctypes callback with char array

ohlfsen <ohlfsen@xxxxxxxxx> writes:

Hello.

Hoping that someone can shed some light on a tiny challenge of mine.

Through ctypes I'm calling a c DLL which requires me to implement a callback in Python/ctypes.

The signature of the callback is something like

void foo(int NoOfElements, char Elements[][100])

How do I possible implement/process "char Elements[][100]" in Python/ctypes code?

I'd try it like this:

$ python
Python 2.7 (r27:82500, May 2 2011, 22:50:11)
[GCC 4.2.1 (Apple Inc. build 5664)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
oWelcome to rlcompleter2 0.98
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from ctypes import *
callback_type = CFUNCTYPE(None, c_int, POINTER(c_char_p))
def my_callback(int, elements):
.... pass
....
c_callback = callback_type(my_callback)
c_callback
<CFunctionType object at 0x100697940>


No need to know that it's a pointer to char[100] pointers - you can cast
that if you want to.

Diez
.

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