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typedef struct _MpdData_real {
	/* MpdDataType */
	MpdDataType type;
    
	union {
		struct {
			int tag_type;
			char *tag;
		};
		char *directory;
		char *playlist; /*is a path*/
		mpd_Song *song;
		mpd_OutputEntity *output_dev; /* from devices */
	};
	struct _MpdData_real *next;
	/* Previous MpdData in the list */
	struct _MpdData_real *prev;
    struct _MpdData_real *first;
}MpdData_real;