How to embedding Python in C++ with PyBind and make instead of CMake?

Question

I am trying to embed some Python code in C++ with PyBind. Most of documentation is on extending Python with C++, but I am interested in embedding:

On http://pybind11.readthedocs.io/en/stable/advanced/embedding.html there is a simple example with cmake. However for my project I have to extend a makefile.

Is it possible to change this example

cmake_minimum_required(VERSION 3.0)
project(example)

find_package(pybind11 REQUIRED)  # or `add_subdirectory(pybind11)`

add_executable(example main.cpp)
target_link_libraries(example PRIVATE pybind11::embed)

with this c++ file

#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
}

to a version with a makefile?

Josh Kelley · Accepted Answer · 2018-06-03 23:25:13Z

2

It's pretty straightforward. You need to make the following changes:

Add the pybind11 include directory to your includes (-I flags).
Add the Python 3 headers to your includes (-I flags).
Add the Python 3 libraries to your libraries (-L flags).

Python's python3-config program is the best way of doing #2 and #3.

For example, if you have a makefile that looks something like this:

%.o: %.cc
    $(CXX) -o $@ -c $^

main: main.o
    $(CXX) -o $@ $^

Then you'll need to change it like this:

%.o: %.cc
    $(CXX) -o $@ -c $^ -Ipath/to/pybind11-2.2.3/include $(shell python3-config --includes)

main: main.o
    $(CXX) -o $@ $^ $(shell python3-config --libs)

In practice, your Makefile probably has variables giving the include paths, C++ compiler flags, libraries, and/or linker flags, so you'd add the -I and python3-config calls there.

answered Jun 3, 2018 at 23:25

Josh Kelley

58.7k22 gold badges166 silver badges259 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Zack Lee Over a year ago

This doesn't seem to really answer the question.

Josh Kelley Over a year ago

@ZackLee, I believe it answers the question - the OP said they need to extend a pre-existing makefile, so I described the changes that they'd need to make to their makefile. If you're writing a makefile from scratch, you could use one of the various examples or templates online, then apply the changes described here.

Collectives™ on Stack Overflow

How to embedding Python in C++ with PyBind and make instead of CMake?

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related