This page contains some coding resources for other programmers.
XSquawkBox CSL SDK
This package provides tools and instructions for making your own CSL packages to extend XSquawkBox's set of multiplayer planes.
Download the XSquawkBox CSL SDK - zip format. Mac OS X users make sure to use the Finder and not StuffIt to decompress.
XSquawkBox Inter-Plugin Communication Protocol
XSquawkBox can communicate with other X-Plane plugins, allowing for scripting of the UI, voice integration for the non-VATSIM version, etc.
Download the XSquawkBox Interplugin Communciation SDK.
Free Source Code: Networking Classes
XSquawkBox uses a series of cross-platform networking classes for TCP and UDP. These classes are C++, offered here under the MIT/X11 license for anyone who is interested. (This is not an FSD protocol implementation, just low level networking classes.)
Download the XSquawkBox Networking Code.
Free Source Code: XSquawkBox Multiplayer Code
XSquawkBox uses a set of classes to manage multiplayer drawing in X-plane; they will be provided here in the future under the MIT/X11 license.