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 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
  * Copyright by The HDF Group.                                               *
  * All rights reserved.                                                      *
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  * terms governing use, modification, and redistribution, is contained in    *
  * the COPYING file, which can be found at the root of the source code       *
  * distribution tree, or in https://www.hdfgroup.org/licenses.               *
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  * help@hdfgroup.org.                                                        *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
 #ifndef H5DOpublic_H
 #define H5DOpublic_H
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 /** \page H5DO_UG HDF5 High Level Optimizations
  * @todo Under Construction
  */
 
 /**\defgroup H5DO HDF5 Optimizations APIs (H5DO)
  *
  * <em>Bypassing default HDF5 behavior in order to optimize for specific
  * use cases (H5DO)</em>
  *
  * HDF5 functions described is this section are implemented in the HDF5 High-level
  * library as optimized functions. These functions generally require careful setup
  * and testing as they enable an application to bypass portions of the HDF5
  * library's I/O pipeline for performance purposes.
  *
  * These functions are distributed in the standard HDF5 distribution and are
  * available any time the HDF5 High-level library is available.
  *
  * - \ref H5DOappend
  *    \n Appends data to a dataset along a specified dimension.
  * - \ref H5DOread_chunk
  *   \n Reads a raw data chunk directly from a dataset in a file into a buffer (DEPRECATED)
  * - \ref H5DOwrite_chunk
  *   \n  Writes a raw data chunk from a buffer directly to a dataset in a file (DEPRECATED)
  *
  */
 
 /*-------------------------------------------------------------------------
  *
  * "Optimized dataset" routines.
  *
  *-------------------------------------------------------------------------
  */
 
 /**
  * --------------------------------------------------------------------------
  * \ingroup H5DO
  *
  * \brief Appends data to a dataset along a specified dimension.
  *
  * \param[in] dset_id   Dataset identifier
  * \param[in] dxpl_id   Dataset transfer property list identifier
  * \param[in] axis      Dataset Dimension (0-based) for the append
  * \param[in] extension Number of elements to append for the
  *                      axis-th dimension
  * \param[in] memtype   The memory datatype identifier
  * \param[in] buf       Buffer with data for the append
  *
  * \return \herr_t
  *
  * \details The H5DOappend() routine extends a dataset by \p extension
  *          number of elements along a dimension specified by a
  *          dimension \p axis and writes \p buf of elements to the
  *          dataset. Dimension \p axis is 0-based. Elements’ type
  *          is described by \p memtype.
  *
  *          This routine combines calling H5Dset_extent(),
  *          H5Sselect_hyperslab(), and H5Dwrite() into a single routine
  *          that simplifies application development for the common case
  *          of appending elements to an existing dataset.
  *
  *          For a multi-dimensional dataset, appending to one dimension
  *          will write a contiguous hyperslab over the other dimensions.
  *          For example, if a 3-D dataset has dimension sizes (3, 5, 8),
  *          extending the 0th dimension (currently of size 3) by 3 will
  *          append 3*5*8 = 120 elements (which must be pointed to by the
  *          \p buffer parameter) to the dataset, making its final
  *          dimension sizes (6, 5, 8).
  *
  *          If a dataset has more than one unlimited dimension, any of
  *          those dimensions may be appended to, although only along
  *          one dimension per call to H5DOappend().
  *
  * \since   1.10.0
  *
  */
 H5_HLDLL herr_t H5DOappend(hid_t dset_id, hid_t dxpl_id, unsigned axis, size_t extension, hid_t memtype,
                            const void *buf);
 
 /* Symbols defined for compatibility with previous versions of the HDF5 API.
  *
  * Use of these symbols is deprecated.
  */
 #ifndef H5_NO_DEPRECATED_SYMBOLS
 
 /* Compatibility wrappers for functionality moved to H5D */
 
 /**
  * --------------------------------------------------------------------------
  * \ingroup H5DO
  *
  * \brief Writes a raw data chunk from a buffer directly to a dataset in a file.
  *
  * \param[in] dset_id       Identifier for the dataset to write to
  * \param[in] dxpl_id       Transfer property list identifier for
  *                          this I/O operation
  * \param[in] filters       Mask for identifying the filters in use
  * \param[in] offset        Logical position of the chunk's first element
  *                          in the dataspace
  * \param[in] data_size     Size of the actual data to be written in bytes
  * \param[in] buf           Buffer containing data to be written to the chunk
  *
  * \return \herr_t
  *
  * \deprecated This function was deprecated in favor of the function
  *             H5Dwrite_chunk() of HDF5-1.10.3.
  *             The functionality of H5DOwrite_chunk() was moved
  *             to H5Dwrite_chunk().
  * \deprecated For compatibility, this API call has been left as a stub which
  *             simply calls H5Dwrite_chunk(). New code should use H5Dwrite_chunk().
  *
  * \details The H5DOwrite_chunk() writes a raw data chunk as specified by its
  *          logical \p offset in a chunked dataset \p dset_id from the application
  *          memory buffer \p buf to the dataset in the file. Typically, the data
  *          in \p buf is preprocessed in memory by a custom transformation, such as
  *          compression. The chunk will bypass the library's internal data
  *          transfer pipeline, including filters, and will be written directly to the file.
  *
  *          \p dxpl_id is a data transfer property list identifier.
  *
  *          \p filters is a mask providing a record of which filters are used
  *          with the chunk. The default value of the mask is zero (\c 0),
  *          indicating that all enabled filters are applied. A filter is skipped
  *          if the bit corresponding to the filter's position in the pipeline
  *          (<tt>0 ≤ position < 32</tt>) is turned on. This mask is saved
  *          with the chunk in the file.
  *
  *          \p offset is an array specifying the logical position of the first
  *          element of the chunk in the dataset's dataspace. The length of the
  *          offset array must equal the number of dimensions, or rank, of the
  *          dataspace. The values in \p offset must not exceed the dimension limits
  *          and must specify a point that falls on a dataset chunk boundary.
  *
  *          \p data_size is the size in bytes of the chunk, representing the number of
  *          bytes to be read from the buffer \p buf. If the data chunk has been
  *          precompressed, \p data_size should be the size of the compressed data.
  *
  *          \p buf is the memory buffer containing data to be written to the chunk in the file.
  *
  * \attention   Exercise caution when using H5DOread_chunk() and H5DOwrite_chunk(),
  *              as they read and write data chunks directly in a file.
  *              H5DOwrite_chunk() bypasses hyperslab selection, the conversion of data
  *              from one datatype to another, and the filter pipeline to write the chunk.
  *              Developers should have experience with these processes before
  *              using this function. Please see
  *              <a href="https://\DOCURL/advanced_topics/UsingDirectChunkWrite.pdf">
  *              Using the Direct Chunk Write Function</a>
  *              for more information.
  *
  * \note    H5DOread_chunk() and H5DOwrite_chunk() are not
  *          supported under parallel and do not support variable length types.
  *
  * \par Example
  * The following code illustrates the use of H5DOwrite_chunk to write
  * an entire dataset, chunk by chunk:
  * \snippet H5DO_examples.c H5DOwrite
  *
  * \version 1.10.3  Function deprecated in favor of H5Dwrite_chunk.
  *
  * \since   1.8.11
  */
 H5_HLDLL herr_t H5DOwrite_chunk(hid_t dset_id, hid_t dxpl_id, uint32_t filters, const hsize_t *offset,
                                 size_t data_size, const void *buf);
 
 /**
  * --------------------------------------------------------------------------
  * \ingroup H5DO
  *
  * \brief Reads a raw data chunk directly from a dataset in a file into a buffer.
  *
  * \param[in] dset_id           Identifier for the dataset to be read
  * \param[in] dxpl_id           Transfer property list identifier for
  *                              this I/O operation
  * \param[in] offset            Logical position of the chunk's first
                                 element in the dataspace
  * \param[in,out] filters       Mask for identifying the filters used
  *                              with the chunk
  * \param[in] buf               Buffer containing the chunk read from
  *                              the dataset
  *
  * \return \herr_t
  *
  * \deprecated This function was deprecated in favor of the function
  *             H5Dread_chunk() as of HDF5-1.10.3.
  *             In HDF5 1.10.3, the functionality of H5DOread_chunk()
  *             was moved to H5Dread_chunk().
  * \deprecated For compatibility, this API call has been left as a stub which
  *             simply calls H5Dread_chunk().  New code should use H5Dread_chunk().
  *
  * \details The H5DOread_chunk() reads a raw data chunk as specified
  *          by its logical \p offset in a chunked dataset \p dset_id
  *          from the dataset in the file into the application memory
  *          buffer \p buf. The data in \p buf is read directly from the file
  *          bypassing the library's internal data transfer pipeline,
  *          including filters.
  *
  *          \p dxpl_id is a data transfer property list identifier.
  *
  *          The mask \p filters indicates which filters are used with the
  *          chunk when written. A zero value indicates that all enabled filters
  *          are applied on the chunk. A filter is skipped if the bit corresponding
  *          to the filter's position in the pipeline
  *          (<tt>0 ≤ position < 32</tt>) is turned on.
  *
  *          \p offset is an array specifying the logical position of the first
  *          element of the chunk in the dataset's dataspace. The length of the
  *          offset array must equal the number of dimensions, or rank, of the
  *          dataspace. The values in \p offset must not exceed the dimension
  *          limits and must specify a point that falls on a dataset chunk boundary.
  *
  *          \p buf is the memory buffer containing the chunk read from the dataset
  *          in the file.
  *
  * \par Example
  * The following code illustrates the use of H5DOread_chunk()
  * to read a chunk from a dataset:
  * \snippet H5DO_examples.c H5DOread
  *
  * \version 1.10.3  Function deprecated in favor of H5Dread_chunk.
  *
  * \since   1.10.2, 1.8.19
  */
 H5_HLDLL herr_t H5DOread_chunk(hid_t dset_id, hid_t dxpl_id, const hsize_t *offset, uint32_t *filters /*out*/,
                                void *buf /*out*/);
 
 #endif /* H5_NO_DEPRECATED_SYMBOLS */
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif

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