Howto:Implementing custom I/O Protocols

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Objective

Demonstrate how to implement a custom I/O protocol using C++

Background

FlightGear supports a plethora of I/O options. Whenever none of the existing protocols works for a particular use-case, people may need to create their own I/O protocol by implemented it in C++ code. For this, FlightGear -and SimGear- provide a handful of APIs and building blocks that allow new protocols to be easily implemented by people familiar with C++.

Hard-coded protocols generally live under $FG_SRC/Network

SGIOChannel

• http://api-docs.freeflightsim.org/simgear/classSGIOChannel.html

Introducing FGProtocol

• https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Network/protocol.hxx
• https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Network/protocol.cxx

Registering your new protocol

• https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Main/options.cxx#l1615
• https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Main/fg_io.cxx#l109

Multi-threading

• SGThread

SGSubsystem-based

• Httpd

SGPropertyChangeListener

• FGCom