Accessing the list of all glyphs in a font

Question

OSStatus                    err;
const char* file = "Lucida Grande";
CFStringRef fileName= CFStringCreateWithCString(0L, file, 0L);
ATSFontRef ref = ATSFontFindFromName (fileName,1);
FSRef oFile;
err = ATSFontGetFileReference (ref, &oFile);

char path [1024*4];
CFURLRef theURL = CFURLCreateFromFSRef( kCFAllocatorDefault, &oFile);
CFURLGetFileSystemRepresentation(theURL,1,(UInt8*)path,1024*4); 
fprintf(stderr,path);

I have written this code. It returns the location of the font. Is there a way to get a list of glyphs available in the font.