Plugin

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Nearly everything in navit is a plugin. A plugin is a shared library which needs to contain a function

void plugin_init(void)

This function is called when the plugin gets loaded. Usually it should call an appropriate

void plugin_init(void) {
	dbg(0, "Enter\n");
	plugin_register_something_type();
	dbg(0, "Exit\n");
}

function.

Unless you know better, start by creating a new folder under /plugin.

Then add Makefile.am and CMakeLists.txt to you plugin directory, so your plugin is built as a module (e.g. libmyplugin.so).

Finally, add a module definition to /CmakeLists.txt, to have it built at all.

add_module(plugin/myplugin "Default" TRUE)

To have the plugin loaded, you need to add it to the <plugins> Object in navit.xml:

	<plugin path="$NAVIT_LIBDIR/*/${NAVIT_LIBPREFIX}libmyplugin.so" active="yes"/>

The j1850 plugin is quite simple and can be a good start if you want to write your own plugin. It demonstrates how to use event callbacks ( using a timeout during the plugin init, or using the idle loop during the regular use), how to add a custom OSD for your plugin, and how to send commands to another plugin (look at the spotify controls).