Ctypes callback example

gistfile1.txt

>>> from ctypes.util import find_library
>>> find_library("c")
'/usr/lib/libc.dylib'
>>> libc = CDLL(find_library("c"))
>>> libc
<CDLL '/usr/lib/libc.dylib', handle 118bf9b80 at 10ea3ecd0>
>>> x = c_int * 5
>>> ia = x(1, 9, 4, 11, 7)
>>> qsort = libc.qsort
>>> qsort.restype = None
>>> CMPFUNC = CFUNCTYPE(c_int, POINTER(c_int), POINTER(c_int))
>>> def py_cmp_func(a, b):
...     print 'asdasd ', a[0], b[0]
...     return 0
... 
>>> cmp_func = CMPFUNC(py_cmp_func)
>>> qsort(ia, len(ia) , sizeof(c_int), cmp_func)
asdasd  1 9
asdasd  9 4
asdasd  4 11
asdasd  11 7
>>> for i in ia:
...     print i
... 
1
9
4
11
7
>>>