C如何调用python

参考资料

https://docs.python.org/zh-cn/3/c-api/ (中文)
https://docs.python.org/3/extending/embedding.html
https://docs.python.org/zh-cn/3/extending/

基本步骤

安装必要的库
sudo apt install libpython3.10-dev

示例python脚本:

# hello.py

def hello_world():
    print("Hello, World from Python!")
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配置CMakeLists:

cmake_minimum_required(VERSION 3.26)
project(lpyl)

set(CMAKE_CXX_STANDARD 11)

add_executable(lpyl main.cpp)

target_link_libraries(
        lpyl
        PRIVATE
        python3.10
)
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编写操作代码:

#include 
#include 

#include 

int main() {
    std::cout << "Hello, World!" << std::endl;
    std::string pythonPathStr = "PYTHONPATH=" + std::string("..");
    putenv(const_cast(pythonPathStr.c_str()));
    Py_Initialize();

    PyObject *pModule = PyImport_ImportModule("hello");
    if (pModule) {
        PyObject *pFunction = PyObject_GetAttrString(pModule, "hello_world");
        if (pFunction && PyCallable_Check(pFunction)) {
            PyObject* pArgs = PyTuple_Pack(0);
            PyObject* pValue = PyObject_CallObject(pFunction, pArgs);
            if (pValue) {
                Py_XDECREF(pValue);
            } else {
                PyErr_Print();
            }
            Py_XDECREF(pFunction);
        } else {
            PyErr_Print();
        }
        Py_XDECREF(pModule);
    } else {
        PyErr_Print();
    }
    Py_Finalize();

    return 0;
}

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输出:

cmake-build-debug/lpyl
Hello, World!
Hello, World from Python!
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