Name: H5Pget_data_transform
Signature:
  ssize_t `H5Pget_data_transform` (hid_t `plist_id`, char *`expression`, size_t `size`)
Purpose:
  Retrieves a data transform expression.
Description:
  `H5Pget_data_transform` retrieves the data transform expression previously set in the dataset transfer property list plist_id by `H5Pset_data_transform`.

  `H5Pget_data_transform` can be used to both retrieve the transform expression and to query its size.

  If `expression` is non-NULL, up to `size` bytes of the data transform expression are written to the buffer. If `expression` is NULL, `size` is ignored and the function does not write anything to the buffer. The function always returns the size of the data transform expression.

  If `0` is returned for the size of the expression, no data transform expression exists for the property list.

  If an error occurs, the buffer pointed to by `expression` is unchanged and the function returns a negative value.

Parameters:

hid_t `plist_id` | IN: Identifier of the property list or class
char *`expression` | OUT: Pointer to memory where the transform expression will be copied
size_t `size` | IN: Number of bytes of the transform expression to copy to

Returns:
  Success: size of the transform expression.
  Failure: a negative value.
Fortran90 Interface: h5pget_data_transform_f

      SUBROUTINE h5pget_data_transform_f(plist_id, expression, hdferr, size)
        IMPLICIT NONE
        INTEGER(HID_T), INTENT(IN) :: plist_id
                                           ! Identifier of the property list or class
        CHARACTER(LEN=*), INTENT(OUT) :: expression
                                           ! Buffer to hold transform expression
        INTEGER(SIZE_T), INTENT(OUT), OPTIONAL :: size
                                           ! Registered size for transform expression
        INTEGER, INTENT(OUT) :: hdferr     ! Error code
                                           ! 0 on success and -1 on failure
      END SUBROUTINE h5pget_data_transform_f

History:

  Release | C
  1.8.0 | Function introduced in this release.