struct my_struct
{
	char arr[3];
};

extern "C" __declspec(dllexport) void func2(struct my_struct * m)
{
	m->arr[0] = 4;
	m->arr[1] = 5;
	m->arr[2] = 6;
};

extern "C" __declspec(dllexport) void func2_arr(struct my_struct ** m)
{
	my_struct *pt = (my_struct*)CoTaskMemAlloc(10 * sizeof my_struct);

	// Присвоение данных
	for (int i = 0; i < 10; i++)
	{
		pt[i].arr[0] = 0;
		pt[i].arr[1] = 1;
		pt[i].arr[2] = 2;
	}
	*m = pt;
};

class MyStruct(Structure):
	_fields_ = ('arr',c_char * 3),

func2 = dll.func2
func2.argtypes = POINTER(MyStruct),
func2.restype = None

m = MyStruct()
func2(m)
print(m.arr[0],m.arr[1],m.arr[2])

func2_arr = dll.func2_arr
func2_arr.argtypes = ndpointer(dtype=MyStruct, shape=(10,)),
func2_arr.restype = None

m2 = ndpointer(dtype=MyStruct, shape=(10,)),
func2_arr(m2)

4 5 6
Traceback (most recent call last):
  File "C:\Users\vvf6426\testLineToc5spot.py", line 56, in <module>
    func2_arr(m2)
ctypes.ArgumentError: argument 1: <class 'TypeError'>: argument must be an ndarray
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