python怎么调用c函数

#include <stdio.h>

#include <stdlib.h>

char * printStr(const char *p,const char *q)

{

    printf("%s",p);

    printf("%s",q);

    return "djstava";

}

gcc -fPIC -shared -o libtest.so test.c

# -*- coding: utf-8 -*-

from ctypes import *

handle = cdll.LoadLibrary('libtest.so')

func = handle.printStr

func.argtypes = (c_char_p,c_char_p)

func.restype = c_char_p

tmp = handle.printStr("hello".encode("utf-8"),"world".encode("utf-8"))

print(tmp.decode("utf-8"))

helloworld

func.argtypes = (c_char_p,c_char_p)

func.restype = c_char_p

handle = cdll.LoadLibrary('libtest.so')

ret = handle.printStr("hello".encode("utf-8"),"world".encode("utf-8"))

__declspec(dllexport) unsigned int crc32( const unsigned char *s, unsigned int len)

{

  unsigned int i;

  unsigned int crc32val=0xffffffff;

printf("len==%d\n",len);

  for (i = 0;  i < len;  i ++)

      crc32val =  crc32_tab[(crc32val ^ s[i]) & 0xff] ^ ((crc32val >> 8)&0x00FFFFFF);

  return ~crc32val;

}

cl /c crc.c

link /dll crc.obj