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These APIs provide facilities to find and work with other plugins and manage other plugins.


These APIs allow you to find another plugin or yourself, or iterate across all plugins. For example, if you wrote an FMS plugin that needed to talk to an autopilot plugin, you could use these APIs to locate the autopilot plugin.


XPLM_API XPLMPluginID         XPLMGetMyID(void);
This routine returns the plugin ID of the calling plug-in. Call this to get your own ID.


XPLM_API int                  XPLMCountPlugins(void);
This routine returns the total number of plug-ins that are loaded, both disabled and enabled.


XPLM_API XPLMPluginID         XPLMGetNthPlugin(
                                   int                  inIndex);    
This routine returns the ID of a plug-in by index. Index is 0 based from 0 to XPLMCountPlugins-1, inclusive. Plugins may be returned in any arbitrary order.


XPLM_API XPLMPluginID         XPLMFindPluginByPath(
                                   const char *         inPath);    
This routine returns the plug-in ID of the plug-in whose file exists at the passed in absolute file system path. XPLM_NO_PLUGIN_ID is returned if the path does not point to a currently loaded plug-in.


XPLM_API XPLMPluginID         XPLMFindPluginBySignature(
                                   const char *         inSignature);    
This routine returns the plug-in ID of the plug-in whose signature matches what is passed in or XPLM_NO_PLUGIN_ID if no running plug-in has this signature. Signatures are the best way to identify another plug-in as they are independent of the file system path of a plug-in or the human-readable plug-in name, and should be unique for all plug-ins. Use this routine to locate another plugin that your plugin interoperates with


XPLM_API void                 XPLMGetPluginInfo(
                                   XPLMPluginID         inPlugin,    
                                   char *               outName,    /* Can be NULL */
                                   char *               outFilePath,    /* Can be NULL */
                                   char *               outSignature,    /* Can be NULL */
                                   char *               outDescription);    /* Can be NULL */

This routine returns information about a plug-in. Each parameter should be a pointer to a buffer of at least 256 characters, or NULL to not receive the information.

outName - the human-readable name of the plug-in. outFilePath - the absolute file path to the file that contains this plug-in. outSignature - a unique string that identifies this plug-in. outDescription - a human-readable description of this plug-in.


These routines are used to work with plug-ins and manage them. Most plugins will not need to use these APIs.


XPLM_API int                  XPLMIsPluginEnabled(
                                   XPLMPluginID         inPluginID);    
Returns whether the specified plug-in is enabled for running.


XPLM_API int                  XPLMEnablePlugin(
                                   XPLMPluginID         inPluginID);    
This routine enables a plug-in if it is not already enabled. It returns 1 if the plugin was enabled or successfully enables itself, 0 if it does not. Plugins may fail to enable (for example, if resources cannot be acquired) by returning 0 from their XPluginEnable callback.


XPLM_API void                 XPLMDisablePlugin(
                                   XPLMPluginID         inPluginID);    
This routine disableds an enabled plug-in.


XPLM_API void                 XPLMReloadPlugins(void);
This routine reloads all plug-ins. Once this routine is called and you return from the callback you were within (e.g. a menu select callback) you will receive your XPluginDisable and XPluginStop callbacks and your DLL will be unloaded, then the start process happens as if the sim was starting up.


Plugin messages are defined as 32-bit integers. Messages below 0x00FFFFFF are reserved for X-Plane and the plugin SDK.

Messages have two conceptual uses: notifications and commands. Commands are sent from one plugin to another to induce behavior; notifications are sent from one plugin to all others for informational purposes. It is important that commands and notifications not have the same values because this could cause a notification sent by one plugin to accidentally induce a command in another.

By convention, plugin-defined notifications should have the high bit set (e.g. be greater or equal to unsigned 0x8000000) while commands should have this bit be cleared.

The following messages are sent to your plugin by x-plane.


This message is sent to your plugin whenever the user's plane crashes.


This message is sent to your plugin whenever a new plane is loaded. The parameter is the number of the plane being loaded; 0 indicates the user's plane.


This messages is called whenever the user's plane is positioned at a new airport. The parameter is of type int, passed as the value of the pointer. (That is: the parameter is an int, not a pointer to an int.)


This message is sent whenever new scenery is loaded. Use datarefs to determine the new scenery files that were loaded.


This message is sent whenever the user adjusts the number of X-Plane aircraft models. You must use XPLMCountPlanes to find out how many planes are now available. This message will only be sent in XP7 and higher because in XP6 the number of aircraft is not user-adjustable.


This message is sent to your plugin whenever a plane is unloaded. The parameter is the number of the plane being unloaded; 0 indicates the user's plane. The parameter is of type int, passed as the value of the pointer. (That is: the parameter is an int, not a pointer to an int.)


This message is sent to your plugin right before X-Plane writes its preferences file. You can use this for two purposes: to write your own preferences, and to modify any datarefs to influence preferences output. For example, if your plugin temporarily modifies saved preferences, you can put them back to their default values here to avoid having the tweaks be persisted if your plugin is not loaded on the next invocation of X-Plane.


This message is sent to your plugin right after a livery is loaded for an airplane. You can use this to check the new livery (via datarefs) and react accordingly. The parameter is of type int, passed as the value of a pointer and represents the aicraft plane number - 0 is the user's plane.


XPLM_API void                 XPLMSendMessageToPlugin(
                                   XPLMPluginID         inPlugin,    
                                   int                  inMessage,    
                                   void *               inParam);    
This function sends a message to another plug-in or X-Plane. Pass XPLM_NO_PLUGIN_ID to broadcast to all plug-ins. Only enabled plug-ins with a message receive function receive the message.

Plugin Features API

The plugin features API allows your plugin to "sign up" for additional capabilities and plugin system features that are normally disabled for backward compatibility. This allows advanced plugins to "opt-in" to new behavior.

Each feature is defined by a permanent string name. The feature string names will vary with the particular installation of X-Plane, so plugins should not expect a feature to be guaranteed present.


typedef void (* XPLMFeatureEnumerator_f)(
                                   const char *         inFeature,    
                                   void *               inRef);    
You pass an XPLMFeatureEnumerator_f to get a list of all features supported by a given version running version of X-Plane. This routine is called once for each feature.


XPLM_API int                  XPLMHasFeature(
                                   const char *         inFeature);    
This returns 1 if the given installation of X-Plane supports a feature, or 0 if it does not.


XPLM_API int                  XPLMIsFeatureEnabled(
                                   const char *         inFeature);    
This returns 1 if a feature is currently enabled for your plugin, or 0 if it is not enabled. It is an error to call this routine with an unsupported feature.


XPLM_API void                 XPLMEnableFeature(
                                   const char *         inFeature,    
                                   int                  inEnable);    
This routine enables or disables a feature for your plugin. This will change the running behavior of X-Plane and your plugin in some way, depending on the feature.


XPLM_API void                 XPLMEnumerateFeatures(
                                   XPLMFeatureEnumerator_f inEnumerator,    
                                   void *               inRef);    
This routine calls your enumerator callback once for each feature that this running version of X-Plane supports. Use this routine to determine all of the features that X-Plane can support.