# Extending and Embedding the Python Interpreter

This document describes how to write modules in C or C++ to extend the Python interpreter with new modules. Those modules can not only define new functions but also new object types and their methods. The document also describes how to embed the Python interpreter in another application, for use as an extension language. Finally, it shows how to compile and link extension modules so that they can be loaded dynamically (at run time) into the interpreter, if the underlying operating system supports this feature.

This document assumes basic knowledge about Python. For an informal introduction to the language, see The Python Tutorial. The Python Language Reference gives a more formal definition of the language. The Python Standard Library documents the existing object types, functions and modules (both built-in and written in Python) that give the language its wide application range.

For a detailed description of the whole Python/C API, see the separate Python/C API Reference Manual.

Note

This guide only covers the basic tools for creating extensions provided as part of this version of CPython. Third party tools may offer simpler alternatives. Refer to the binary extensions section in the Python Packaging User Guide for more information.

- 1. Extending Python with C or C++
  - 1.1. A Simple Example
  - 1.2. Intermezzo: Errors and Exceptions
  - 1.3. Back to the Example
  - 1.4. The Module’s Method Table and Initialization Function
  - 1.5. Compilation and Linkage
  - 1.6. Calling Python Functions from C
  - 1.7. Extracting Parameters in Extension Functions
  - 1.8. Keyword Parameters for Extension Functions
  - 1.9. Building Arbitrary Values
  - 1.10. Reference Counts
  - 1.11. Writing Extensions in C++
  - 1.12. Providing a C API for an Extension Module
- 2. Defining New Types
  - 2.1. The Basics
  - 2.2. Type Methods
- 3. Building C and C++ Extensions with distutils
  - 3.1. Distributing your extension modules
- 4. Building C and C++ Extensions on Windows
  - 4.1. A Cookbook Approach
  - 4.2. Differences Between Unix and Windows
  - 4.3. Using DLLs in Practice
- 5. Embedding Python in Another Application
  - 5.1. Very High Level Embedding
  - 5.2. Beyond Very High Level Embedding: An overview
  - 5.3. Pure Embedding
  - 5.4. Extending Embedded Python
  - 5.5. Embedding Python in C++
  - 5.6. Compiling and Linking under Unix-like systems