format  Sint32 GFS_SetTmode (GfsHngfs, Sint32 tmode)
 Input  gfs: File handle
:  tmode: Transfer mode (GFS_TMODE_ ~)
 Output  None
 Function value  Transfer mode before setting. Negative error code in case of error.
 Function  Set the transfer method from the CD buffer. 

  format  Sint32 GFS_SetReadPara (GfsHngfs, Sint32 cdrsize)
 Input  gfs: File handle
:  cdrsize: Maximum amount of data read into the CD buffer at one time (unit: sector)
 Output  None
 Function value  Amount read before setting. Negative error code in case of error.
 Function  Sets the maximum value for one reading into the CD buffer. 

  format  Sint32 GFS_SetTransPara (GfsHngfs, Sint32 tsize)
 Input  gfs: File handle
 t  tsize: Amount transferred at once to the specified area (unit: sector)
 Output  None
 Function value  Transfer amount before setting. Negative error code in case of error.
 Function  Sets the amount of data transferred to the transfer destination area in one retrieval process. 

  format  void GFS_SetTrFunc (GfsHngfs, GfsTrFunc func)
 Input  gfs: File handle
  func: Transfer function
 Output  None
 Function value  None
 Function  Registers the transfer function for the specified file.
  registration function is called during file transfer processing.
 Remarks  (a) The registration function has the following format.
  Sint32 (* GfsTrFunc) (GfsHngfs, Sint32 nsct)
: : gfs: File handle
  nsct: Number of sectors that can be transferred
  (b) The transfer function can transfer data of up to nsct sectors.
:  (c) Returns the number of sectors actually transferred in the function value.
:  If transfer is in progress at the end of the transfer function, such as DMA, (-1) must be returned.
 Example  / * Transfer function example * /
  Uint32 read_buf [BUFSIZE];
 S  Sint32 transFunc (GfsHngfs, Sint32 nsct)
  {
  Uint32 * ptr;
  Sint32 dadr;
  Sint32 i;
  ptr = GFS_StartTrans (gfs, & dadr);
  for for (i = 0; i <2048 * nsct; i ++) {
  read_buf [i] = * ptr;
  ptr + = dadr;
 }
  return (nsct);
 }