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Python是解释性语言, 底层就是用c实现的, 所以用python调用C是很容易的, 下面就总结一下各种调用的方法, 给出例子, 所有例子都在ubuntu9.10, python2.6下试过.
1. Python 调用 C (base)
想在python中调用c函数, 如这儿的fact
#include
int fact(int n) { if (n <= 1) return 1; else return n * fact(n - 1); } PyObject* wrap_fact(PyObject* self, PyObject* args) { int n, result; if (! PyArg_ParseTuple(args, "i:fact", &n)) return NULL; result = fact(n); return Py_BuildValue("i", result); } static PyMethodDef exampleMethods[] = { {"fact", wrap_fact, METH_VARARGS, "Caculate N!"}, {NULL, NULL} }; void initexample() { PyObject* m; m = Py_InitModule("example", exampleMethods); }把这段代码存为wrapper.c, 编成so库,
gcc -fPIC wrapper.c -o example.so -shared -I/usr/include/python2.6 -I/usr/lib/python2.6/config
然后在有此so库的目录, 进入python, 可以如下使用
import example
example.fact(4)
2. Python 调用 C++ (base)
在python中调用C++类成员函数, 如下调用TestFact类中的fact函数,
#include
class TestFact{ public: TestFact(){}; ~TestFact(){}; int fact(int n); }; int TestFact::fact(int n) { if (n <= 1) return 1; else return n * (n - 1); } int fact(int n) { TestFact t; return t.fact(n); }PyObject* wrap_fact(PyObject* self, PyObject* args)
{ int n, result; if (! PyArg_ParseTuple(args, "i:fact", &n)) return NULL; result = fact(n); return Py_BuildValue("i", result); } static PyMethodDef exampleMethods[] = { {"fact", wrap_fact, METH_VARARGS, "Caculate N!"}, {NULL, NULL} }; extern "C" //不加会导致找不到initexample void initexample() { PyObject* m; m = Py_InitModule("example", exampleMethods); }
把这段代码存为wrapper.cpp, 编成so库,
g++ -fPIC wrapper.cpp -o example.so -shared -I/usr/include/python2.6 -I/usr/lib/python2.6/config
然后在有此so库的目录, 进入python, 可以如下使用
import example
example.fact(4)
3. Python 调用 C++ (Boost.Python)
Boost库是非常强大的库, 其中的python库可以用来封装c++被python调用, 功能比较强大, 不但可以封装函数还能封装类, 类成员.
http://dev.gameres.com/Program/Abstract/Building%20Hybrid%20Systems%20with%20Boost_Python.CHN.by.JERRY.htm
首先在ubuntu下安装boost.python, apt-get install libboost-python-dev
#include
char const* greet() { return "hello, world"; } BOOST_PYTHON_MODULE(hello) { using namespace boost::python; def("greet", greet); }把代码存为hello.cpp, 编译成so库
g++ hello.cpp -o hello.so -shared -I/usr/include/python2.5 -I/usr/lib/python2.5/config -lboost_python-gcc42-mt-1_34_1
此处python路径设为你的python路径, 并且必须加-lboost_python-gcc42-mt-1_34_1, 这个库名不一定是这个, 去/user/lib查
然后在有此so库的目录, 进入python, 可以如下使用
>>> import hello
>>> hello.greet() 'hello, world'
4. python 调用 c++ (ctypes)
ctypes is an advanced ffi (Foreign Function Interface) package for 2.3 and higher. In 2.5 it is already included.
ctypes allows to call functions in dlls/shared libraries and has extensive facilities to create, access and manipulate simple and complicated C data types in Python - in other words: wrap libraries in pure Python. It is even possible to implement C callback functions in pure Python.
http://python.net/crew/theller/ctypes/
#include
class TestFact{ public: TestFact(){}; ~TestFact(){}; int fact(int n); }; int TestFact::fact(int n) { if (n <= 1) return 1; else return n * (n - 1); } extern "C" int fact(int n) { TestFact t; return t.fact(n); } 将代码存为wrapper.cpp不用写python接口封装, 直接编译成so库,g++ -fPIC wrapper.cpp -o example.so -shared -I/usr/include/python2.6 -I/usr/lib/python2.6/config
进入python, 可以如下使用
>>> import ctypes >>> pdll = ctypes.CDLL('/home/ubuntu/tmp/example.so') >>> pdll.fact(4) 12转载地址：http://pifob.baihongyu.com/