您是否遇到过必须使用Python调用C函数的情况?本文将在一个非常基础的水平上为您提供帮助，如果您没有遇到过这种情况，您将很高兴知道如何实现。
首先，让我们使用C编写一个简单的函数，并生成文件的共享库。假设文件名是函数.c。
C
int myFunction(int num)
{
if (num == 0)
// if number is 0, do not perform any operation.
return 0;
else
// if number is power of 2, return 1 else return 0
return ((num & (num - 1)) == 0 ? 1 : 0) ;
}Python3
import ctypes
NUM = 16
# libfun loaded to the python file
# using fun.myFunction(),
# C function can be accessed
# but type of argument is the problem.
fun = ctypes.CDLL("libfun.so") # Or full path to file
# Now whenever argument
# will be passed to the function
# ctypes will check it.
fun.myFunction.argtypes = [ctypes.c_int]
# now we can call this
# function using instant (fun)
# returnValue is the value
# return by function written in C
# code
returnVale = fun.myFunction(NUM)编译：
cc -fPIC -shared -o libfun.so function.c使用ctypes(外部函数接口)库从Python调用C函数
上面的语句将生成一个名为libfun.so的共享库。现在，让我们看看如何在Python使用它。在Python，我们有一个名为ctypes的库。使用这个库，我们可以在Python使用C函数。
假设文件名是函数.py。
Python3
import ctypes
NUM = 16
# libfun loaded to the python file
# using fun.myFunction(),
# C function can be accessed
# but type of argument is the problem.
fun = ctypes.CDLL("libfun.so") # Or full path to file
# Now whenever argument
# will be passed to the function
# ctypes will check it.
fun.myFunction.argtypes = [ctypes.c_int]
# now we can call this
# function using instant (fun)
# returnValue is the value
# return by function written in C
# code
returnVale = fun.myFunction(NUM)