308 typedef struct DVDCommandBlock DVDCommandBlock;  typedef
312 struct DVDCommandBlock  struct
314     DVDCommandBlock* next;  argument
315     DVDCommandBlock* prev;  argument
316     u32              command;
317     s32              state;
318     u32              offset;
319     u32              length;
320     void*            addr;
321     u32              currTransferSize;
322     u32              transferredSize;
346     DVDCommandBlock cb;  argument