Track layout.

typedef struct _TRACKLAYOUT {
  BYTE       bCommand;        /*  Command information. */
  USHORT     usHead;          /*  Physical head on the device that performs the operation. */
  USHORT     usCylinder;      /*  Cylinder to be written, read, or verified. */
  USHORT     usFirstSector;   /*  Logical sector number within the Track Layout Table that starts the I/O operation. */
  USHORT     cSectors;        /*  Number of sectors to read, write, or verify. */
  struct   {
    USHORT       usSectorNumber;  /*  Sector number. */
    USHORT       usSectorSize;    /*  Sector size. */
  } TrackTable[1];
} TRACKLAYOUT;

typedef   TRACKLAYOUT   * PTRACKLAYOUT ;