Preferences structure definition

typedef struct {
	int skeletonData;
} Prefs;

Prefs prefs;

Open preferences

void startApp() {
	Int16 prefSize = sizeof(Prefs);
	if ((PrefGetAppPreferences (AppCreator, 
			 		1000, // pref database id
			 		&prefs, 
			 		&prefSize, 
		 	 		true) // saved during Hotsync
		== noPreferenceFound) 
		|| (prefSize != sizeof(Prefs))) {
					// default initialization, since discovered 
					// Prefs was missing or old.
		prefs.skeletonData=1;
	}
}

Write preferences

void stopApp() {
	PrefSetAppPreferences (AppCreator, 
				1000,	// pref database id
				1, 	// version of pref database
				&prefs, 
				sizeof(Prefs), 
				true);	// saved during hotsync
}

Load and initializing the library

#include 
int MathLibRef = -1;
...
// is library already loaded?
err = SysLibFind("MathLib", &MathLibRef);
if (err != 0) {
	// negative, load
	err = SysLibLoad('libr', 'MthL', &MathLibRef);
	if (err == 0) {
		err = MathLibOpen (MathLibRef, 1);
	}
}

Closing library

if (MathLibRef != -1) {
	Err err;
	UInt16 usecount;
	err = MathLibClose (MathLibRef, &usecount);
	if (usecount == 0) {
		SysLibRemove (MathLibRef);
	}
}