python ctypes调用C函数

python可以用ctypes库调用C函数

1.生成.dll（windows下）或.so（linux下）文件

//pycall.c
#include <stdio.h>
#include <stdlib.h>
int foo(int a, int b) 
{ 
　　printf("you input %d and %d\n", a, b); 
　　return a+b; 
}

#For Windows

　　生成dll文件.

gcc -Wall -shared pycall.c -o pycall.dll

　　或者

gcc --share pycall.c -o pycall.dll

#For Linux

　　生成so文件.

gcc -o pycall.so -shared -fPIC pycall.c

#For Mac

gcc -shared -Wl,-install_name,adder.so -o adder.so -fPIC add.c

2.ctypes调用

#下面是加载dll方法：
#stdcall调用约定：两种加载方式 ：Objdll = ctypes.windll.LoadLibrary("dllpath")和Objdll = ctypes.WinDLL("dllpath")
#cdecl调用约定：也有两种加载方式：Objdll = ctypes.cdll.LoadLibrary("dllpath")和Objdll = ctypes.CDLL("dllpath")

import ctypes
#1
ll = ctypes.cdll.LoadLibrary("./pycall.so")
ll1=ctypes.cdll.LoadLibrary("./pycall.dll")
#2
ll3=ctypes.windll.LoadLibrary("./pycall.so")
ll4=ctypes.WinDLL("./pycall.dll")
#3
ll5=ctypes.CDLL("./pycall.so")
ll6=ctypes.CDLL("./pycall.dll")

ll1.foo(2,4)
ll3.foo(5,6)
ll4.foo(7,8)
ll5.foo(9,10)
ll6.foo(11,12)
print( '***finish***')

***finish***
you input 2 and 4
you input 5 and 6
you input 7 and 8
you input 9 and 10
you input 11 and 12