在Python中将multiprocessing.Array转换为ctypes.c_void_p

Question

我需要将multiprocessing.Array转换为c_void_p。目前这就是我所拥有的：

shared_mem_bfr = multiprocessing.Array(c_uint8, img_width*img_height*3)
npyarr = np.frombuffer(shared_mem_bfr.get_obj(), c_uint8)
memory_buffer = npyarr.ctypes.data_as(c_void_p)

困扰我的是我首先将其转换为Numpy数组然后转换为c_void_p。有没有办法删除中间步骤？

Answer 1

使用ctypes.addressof：

import numpy as np
import multiprocessing as mp
import ctypes as c

shared_mem_bfr = mp.Array(c.c_uint8, 100)
print(c.c_void_p(c.addressof(shared_mem_bfr.get_obj())))

npyarr = np.frombuffer(shared_mem_bfr.get_obj(), c.c_uint8)
memory_buffer = npyarr.ctypes.data_as(c.c_void_p)
print(memory_buffer)

输出：

c_void_p(1552895115472)
c_void_p(1552895115472)