File: gawk.info,  Node: Extension API Description,  Next: Finding Extensions,  Prev: Extension Mechanism Outline,  Up: Dynamic Extensions

17.4 API Description
====================

C or C++ code for an extension must include the header file 'gawkapi.h',
which declares the functions and defines the data types used to
communicate with 'gawk'.  This (rather large) minor node describes the
API in detail.

* Menu:

* Extension API Functions Introduction:: Introduction to the API functions.
* General Data Types::                   The data types.
* Memory Allocation Functions::          Functions for allocating memory.
* Constructor Functions::                Functions for creating values.
* API Ownership of MPFR and GMP Values:: Managing MPFR and GMP Values.
* Registration Functions::               Functions to register things with
                                         'gawk'.
* Printing Messages::                    Functions for printing messages.
* Updating ERRNO::                Functions for updating 'ERRNO'.
* Requesting Values::                    How to get a value.
* Accessing Parameters::                 Functions for accessing parameters.
* Symbol Table Access::                  Functions for accessing global
                                         variables.
* Array Manipulation::                   Functions for working with arrays.
* Redirection API::                      How to access and manipulate
                                         redirections.
* Extension API Variables::              Variables provided by the API.
* Extension API Boilerplate::            Boilerplate code for using the API.
* Changes from API V1::                  Changes from V1 of the API.