Calling python from a c++ program for distribution

I would like to call python script files from my c++ program.

I am not sure that the people I will distribute to will have python installed.

Basically I’m looking for a .lib file that I can use that has an Apache like distribution license.

Answers:

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Method 1

I would like to call python script files from my c++ program.

This means that you want to embed Python in your C++ application. As mentioned in Embedding Python in Another Application:

Embedding Python is similar to
extending it, but not quite. The
difference is that when you extend
Python, the main program of the
application is still the Python
interpreter, while if you embed
Python, the main program may have
nothing to do with Python — instead,
some parts of the application
occasionally call the Python
interpreter to run some Python code.

I suggest that you first go through Embedding Python in Another Application. Then refer the following examples

1. Embedding Python in C/C++: Part I
2. Embedding Python in C/C++: Part II
3. Embedding Python in Multi-Threaded C/C++ Applications

If you like Boost.Python, you may visit the following links:

1. Embedding Python with Boost.Python Part 1

Method 2

Boost has a python interface library which could help you.

Boost.Python

Method 3

Interestingly, nobody has mentioned pybind11, yet. From their documentation:

pybind11 is a lightweight header-only library that exposes C++ types
in Python and vice versa, mainly to create Python bindings of existing
C++ code. Its goals and syntax are similar to the excellent
Boost.Python library by David Abrahams: to minimize boilerplate code
in traditional extension modules by inferring type information using
compile-time introspection. […] Since its creation, this library has
grown beyond Boost.Python in many ways, leading to dramatically
simpler binding code in many common situations.

Concretely, calling into a Python function (called embedding) is as simple as this (taken from the documentation):

#include <pybind11/embed.h> // everything needed for embedding
namespace py = pybind11;

int main() {
    py::scoped_interpreter guard{}; // start the interpreter and keep it alive
    py::print("Hello, World!"); // use the Python API
}

Method 4

Use system call to run a python script from C++

#include<iostream>
#include <cstdlib>
using namespace std;
int main ()
{
int result = system("/usr/bin/python3 testGen1.py 1");
cout << result; 
}

Method 5

Embeding the Python interpreter inside your C++ app will let you run Python programs using your application run Python scripts. It will also make it easier possible for those scripts to call C++ functions in your application. If this is what you want then the Boost library mentioned previously may be what you want to make it easier to create the link. In the past I have used SWIG to generate Python interfaces to C++ code. It was not clear from your question whether you wanted the Python scripts to call your C++ program or whether you just wanted the C++ to call Python.

Many of the Python functions use modules which are not built into the Python interpreter. If your Python scripts call these functions then you will either need to have your users install Python or include the python runtime files with your application. It will depend on what modules you import in you Python scripts.

Method 6

Boost is probably the best choice, however if you’re wanting something that’s more standalone, and if this is for use with Windows (which seems feasible given that they are the people least likely to have Python installed), then you can use py2exe to create a DLL with entry points suitable for COM objects. You can then interface with the library via COM. (Obviously this is not at all useful as a cross-platform solution).

Method 7

Using Inter Process Communication (IPC) over socket can be a possible solution. Use a local network socket to listen/trasfer commands between both.

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0