Here is a list of all documented files with brief descriptions:

broker.h	Library for configuring and using the gateway's message broker
dynamic_loader.h	Library for loading gateway modules from dynamically-linked libraries (Windows) or shared objects (Linux)
gateway.h	Library that allows a user to create and configure a gateway
message.h	Defines structures and function prototypes for creating, inspecting and disposing of messages published to the message broker
module.h	Interface for modules which communicate with other modules via a message broker
module_loader.h	Definition of the functions and structures that must be implemented by a gateway module loader