path: root/src/H5Opublic.h

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * 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.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*-------------------------------------------------------------------------
 *
 * Created:             H5Opublic.h
 *                      Aug  5 1997
 *                      Robb Matzke
 *
 * Purpose:             Public declarations for the H5O (object header)
 *                      package.
 *
 *-------------------------------------------------------------------------
 */
#ifndef H5Opublic_H
#define H5Opublic_H

/* Public headers needed by this file */
#include "H5public.h"  /* Generic Functions            */
#include "H5Ipublic.h" /* IDs                          */
#include "H5Lpublic.h" /* Links                        */

/*****************/
/* Public Macros */
/*****************/

/* Flags for object copy (H5Ocopy) */
#define H5O_COPY_SHALLOW_HIERARCHY_FLAG     (0x0001u) /**< Copy only immediate members */
#define H5O_COPY_EXPAND_SOFT_LINK_FLAG      (0x0002u) /**< Expand soft links into new objects */
#define H5O_COPY_EXPAND_EXT_LINK_FLAG       (0x0004u) /**< Expand external links into new objects */
#define H5O_COPY_EXPAND_REFERENCE_FLAG      (0x0008u) /**< Copy objects that are pointed by references */
#define H5O_COPY_WITHOUT_ATTR_FLAG          (0x0010u) /**< Copy object without copying attributes */
#define H5O_COPY_PRESERVE_NULL_FLAG         (0x0020u) /**< Copy NULL messages (empty space) */
#define H5O_COPY_MERGE_COMMITTED_DTYPE_FLAG (0x0040u) /**< Merge committed datatypes in dest file */
#define H5O_COPY_ALL                        (0x007Fu) /**< All object copying flags (for internal checking) */

/* Flags for shared message indexes.
 * Pass these flags in using the mesg_type_flags parameter in
 * H5P_set_shared_mesg_index.
 * (Developers: These flags correspond to object header message type IDs,
 * but we need to assign each kind of message to a different bit so that
 * one index can hold multiple types.)
 */
#define H5O_SHMESG_NONE_FLAG    0x0000                  /**< No shared messages */
#define H5O_SHMESG_SDSPACE_FLAG ((unsigned)1 << 0x0001) /**< Simple Dataspace Message.  */
#define H5O_SHMESG_DTYPE_FLAG   ((unsigned)1 << 0x0003) /**< Datatype Message.  */
#define H5O_SHMESG_FILL_FLAG    ((unsigned)1 << 0x0005) /**< Fill Value Message. */
#define H5O_SHMESG_PLINE_FLAG   ((unsigned)1 << 0x000b) /**< Filter pipeline message.  */
#define H5O_SHMESG_ATTR_FLAG    ((unsigned)1 << 0x000c) /**< Attribute Message.  */
#define H5O_SHMESG_ALL_FLAG                                                                                  \
    (H5O_SHMESG_SDSPACE_FLAG | H5O_SHMESG_DTYPE_FLAG | H5O_SHMESG_FILL_FLAG | H5O_SHMESG_PLINE_FLAG |        \
     H5O_SHMESG_ATTR_FLAG)

/* clang-format off */
/* Object header status flag definitions */
#define H5O_HDR_CHUNK0_SIZE             0x03 /**< 2-bit field indicating # of bytes to store the size of chunk 0's data */
#define H5O_HDR_ATTR_CRT_ORDER_TRACKED  0x04 /**< Attribute creation order is tracked */
#define H5O_HDR_ATTR_CRT_ORDER_INDEXED  0x08 /**< Attribute creation order has index */
#define H5O_HDR_ATTR_STORE_PHASE_CHANGE 0x10 /**< Non-default attribute storage phase change values stored */
#define H5O_HDR_STORE_TIMES             0x20 /**< Store access, modification, change & birth times for object */
#define H5O_HDR_ALL_FLAGS                                                                                    \
    (H5O_HDR_CHUNK0_SIZE | H5O_HDR_ATTR_CRT_ORDER_TRACKED | H5O_HDR_ATTR_CRT_ORDER_INDEXED |                 \
     H5O_HDR_ATTR_STORE_PHASE_CHANGE | H5O_HDR_STORE_TIMES)
/* clang-format on */

/* Maximum shared message values.  Number of indexes is 8 to allow room to add
 * new types of messages.
 */
#define H5O_SHMESG_MAX_NINDEXES  8
#define H5O_SHMESG_MAX_LIST_SIZE 5000

/* Flags for H5Oget_info.
 * These flags determine which fields will be filled in the H5O_info_t
 * struct.
 */
#define H5O_INFO_BASIC     0x0001u /**< Fill in the fileno, addr, type, and rc fields */
#define H5O_INFO_TIME      0x0002u /**< Fill in the atime, mtime, ctime, and btime fields */
#define H5O_INFO_NUM_ATTRS 0x0004u /**< Fill in the num_attrs field */
#define H5O_INFO_ALL       (H5O_INFO_BASIC | H5O_INFO_TIME | H5O_INFO_NUM_ATTRS)

//! <!-- [H5O_native_info_fields_snip] -->
/**
 * Flags for H5Oget_native_info().  These flags determine which fields will be
 * filled in the \ref H5O_native_info_t struct.
 */
#define H5O_NATIVE_INFO_HDR       0x0008u /**< Fill in the hdr field */
#define H5O_NATIVE_INFO_META_SIZE 0x0010u /**< Fill in the meta_size field */
#define H5O_NATIVE_INFO_ALL       (H5O_NATIVE_INFO_HDR | H5O_NATIVE_INFO_META_SIZE)
//! <!-- [H5O_native_info_fields_snip] -->

/* Convenience macro to check if the token is the 'undefined' token value */
#define H5O_IS_TOKEN_UNDEF(token) (!HDmemcmp(&(token), &(H5O_TOKEN_UNDEF), sizeof(H5O_token_t)))

/*******************/
/* Public Typedefs */
/*******************/

//! <!-- [H5O_type_t_snip] -->
/**
 * Types of objects in file
 */
typedef enum H5O_type_t {
    H5O_TYPE_UNKNOWN = -1,   /**< Unknown object type        */
    H5O_TYPE_GROUP,          /**< Object is a group          */
    H5O_TYPE_DATASET,        /**< Object is a dataset        */
    H5O_TYPE_NAMED_DATATYPE, /**< Object is a named data type    */
    H5O_TYPE_MAP,            /**< Object is a map */
    H5O_TYPE_NTYPES          /**< Number of different object types (must be last!) */
} H5O_type_t;
//! <!-- [H5O_type_t_snip] -->

//! <!-- [H5O_hdr_info_t_snip] -->
/**
 * Information struct for object header metadata (for
 * H5Oget_info(), H5Oget_info_by_name(), H5Oget_info_by_idx())
 */
typedef struct H5O_hdr_info_t {
    unsigned version; /**< Version number of header format in file */
    unsigned nmesgs;  /**< Number of object header messages */
    unsigned nchunks; /**< Number of object header chunks */
    unsigned flags;   /**< Object header status flags */
    struct {
        hsize_t total; /**< Total space for storing object header in file */
        hsize_t meta;  /**< Space within header for object header metadata information */
        hsize_t mesg;  /**< Space within header for actual message information */
        hsize_t free;  /**< Free space within object header */
    } space;
    struct {
        uint64_t present; /**< Flags to indicate presence of message type in header */
        uint64_t shared;  /**< Flags to indicate message type is shared in header */
    } mesg;
} H5O_hdr_info_t;
//! <!-- [H5O_hdr_info_t_snip] -->

//! <!-- [H5O_info2_t_snip] -->
/**
 * Data model information struct for objects
 * (For H5Oget_info(), H5Oget_info_by_name(), H5Oget_info_by_idx() version 3)
 */
typedef struct H5O_info2_t {
    unsigned long fileno;    /**< File number that object is located in */
    H5O_token_t   token;     /**< Token representing the object        */
    H5O_type_t    type;      /**< Basic object type (group, dataset, etc.) */
    unsigned      rc;        /**< Reference count of object            */
    time_t        atime;     /**< Access time                          */
    time_t        mtime;     /**< Modification time                    */
    time_t        ctime;     /**< Change time                          */
    time_t        btime;     /**< Birth time                           */
    hsize_t       num_attrs; /**< Number of attributes attached to object   */
} H5O_info2_t;
//! <!-- [H5O_info2_t_snip] -->

//! <!-- [H5O_native_info_t_snip] -->
/**
 * Native file format information struct for objects.
 * (For H5Oget_native_info(), H5Oget_native_info_by_name(), H5Oget_native_info_by_idx())
 */
typedef struct H5O_native_info_t {
    H5O_hdr_info_t hdr; /**< Object header information */
    struct {
        H5_ih_info_t obj;  /**< v1/v2 B-tree & local/fractal heap for groups, B-tree for chunked datasets */
        H5_ih_info_t attr; /**< v2 B-tree & heap for attributes */
    } meta_size;           /**< Extra metadata storage for obj & attributes */
} H5O_native_info_t;
//! <!-- [H5O_native_info_t_snip] -->

/**
 * Typedef for message creation indexes
 */
typedef uint32_t H5O_msg_crt_idx_t;

//! <!-- [H5O_iterate2_t_snip] -->
/**
 * Prototype for H5Ovisit(), H5Ovisit_by_name() operator (version 3)
 *
 * \param[in] obj Object that serves as the root of the iteration;
 *                the same value as the H5Ovisit3() \c obj_id parameter
 * \param[in] name Name of object, relative to \p obj, being examined at current
 *                 step of the iteration
 * \param[out] info Information about that object
 * \param[in,out] op_data User-defined pointer to data required by the application
 *                        in processing the object; a pass-through of the \c op_data
 *                        pointer provided with the H5Ovisit3() function call
 * \return \herr_t_iter
 *
 */
typedef herr_t (*H5O_iterate2_t)(hid_t obj, const char *name, const H5O_info2_t *info, void *op_data);
//! <!-- [H5O_iterate2_t_snip] -->

//! <!-- [H5O_mcdt_search_ret_t_snip] -->
typedef enum H5O_mcdt_search_ret_t {
    H5O_MCDT_SEARCH_ERROR = -1, /**< Abort H5Ocopy */
    H5O_MCDT_SEARCH_CONT, /**< Continue the global search of all committed datatypes in the destination file
                           */
    H5O_MCDT_SEARCH_STOP  /**< Stop the search, but continue copying.  The committed datatype will be copied
                             but not merged. */
} H5O_mcdt_search_ret_t;
//! <!-- [H5O_mcdt_search_ret_t_snip] -->

//! <!-- [H5O_mcdt_search_cb_t_snip] -->
/**
 * Callback to invoke when completing the search for a matching committed
 * datatype from the committed dtype list
 */
typedef H5O_mcdt_search_ret_t (*H5O_mcdt_search_cb_t)(void *op_data);
//! <!-- [H5O_mcdt_search_cb_t_snip] -->

/********************/
/* Public Variables */
/********************/

/*********************/
/* Public Prototypes */
/*********************/
#ifdef __cplusplus
extern "C" {
#endif

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Opens an object in an HDF5 file by location identifier and path name.
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Path to the object; relative to \p loc_id
 * \lapl_id
 *
 * \return \hid_tv{object}
 *
 * \details H5Oopen() opens a group, dataset, or committed (named) datatype
 *          specified by a location, \p loc_id, and a path name, \p name, in an HDF5 file.
 *
 *          This function opens the object in the same manner as H5Gopen(), H5Topen(), and H5Dopen().
 *          However, H5Oopen() does not require the type of object to be known beforehand.
 *          This can be useful with user-defined links, for instance, when only a path may be known.
 *
 *          H5Oopen() cannot be used to open a dataspace, attribute, property list, or file.
 *
 *          Once an object of unknown type has been opened with H5Oopen(),
 *          the type of that object can be determined by means of an H5Iget_type() call.
 *
 *          \p loc_id may be a file, group, dataset, named datatype, or attribute.
 *          If an attribute is specified for \p loc_id then the object where the
 *          attribute is attached will be accessed.
 *
 *          \p name must be the path to that object relative to \p loc_id.
 *
 *          \p lapl_id is the link access property list associated with the link pointing to
 *          the object.  If default link access properties are appropriate, this can be
 *          passed in as #H5P_DEFAULT.
 *
 *          When it is no longer needed, the opened object should be closed with
 *          H5Oclose(), H5Gclose(), H5Tclose(), or H5Dclose().
 *
 * \version 1.8.1 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL hid_t H5Oopen(hid_t loc_id, const char *name, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Opens an object in an HDF5 file using its VOL independent token
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] token Object token
 *
 * \return \hid_ti{object}
 *
 * \details H5Oopen_by_token() opens an object specified by the object
 *          identifier, \p loc_id and object token, \p token.
 *
 * \since 1.12.0
 *
 */
H5_DLL hid_t H5Oopen_by_token(hid_t loc_id, H5O_token_t token);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Opens the nth object in a group
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] group_name Name of group, relative to \p loc_id, in which object is located
 * \idx_type
 * \order
 * \param[in] n Object to open
 * \lapl_id
 *
 * \return \hid_tv{object}
 *
 * \details H5Oopen_by_idx() opens the nth object in the group specified by \p loc_id
 *          and \p group_name.
 *
 *          \p loc_id specifies a location identifier.
 *          \p group_name specifies the group relative to \p loc_id in which the object can be found.
 *          If \p loc_id fully specifies the group in which the object resides,
 *          \p group_name can be a dot (.).
 *
 *          The specific object to be opened within the group is specified by the three parameters:
 *          \p idx_type, \p order and \p n.
 *
 *          \p idx_type specifies the type of index by which objects are ordered.
 *          Valid index types include the following:
 *
 *          \indexes
 *
 *          \p order specifies the order in which the objects are to be referenced for the purposes
 *          of this function.  Valid orders include the following:
 *
 *          \orders
 *
 *          Note that for #H5_ITER_NATIVE, rather than implying a particular order,
 *          it instructs the HDF5 library to iterate through the objects in the fastest
 *          available order, i.e., in a natural order.
 *
 *          \p n specifies the position of the object within the index.  Note that this count is
 *          zero-based; 0 (zero) indicates that the function will return the value of the first object;
 *          if \p n is 5, the function will return the value of the sixth object; etc.
 *
 *          \p lapl_id specifies the link access property list to be used in accessing the object.
 *
 *          An object opened with this function should be closed when it is no longer needed so that
 *          resource leaks will not develop.  H5Oclose() can be used to close groups, datasets,
 *          or committed datatypes.
 *
 * \version 1.8.1 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL hid_t H5Oopen_by_idx(hid_t loc_id, const char *group_name, H5_index_t idx_type, H5_iter_order_t order,
                            hsize_t n, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Determines whether a link resolves to an actual object.
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name The name of the link to check
 * \lapl_id
 *
 * \return Returns a positive value if the object pointed to by
 *         the \p loc_id and \p name combination exists.
 * \return Returns 0 if the object pointed to by
 *         the \p loc_id and \p name combination does not exist.
 * \return Returns a negatvie value when the function fails.
 *
 * \details H5Oexists_by_name() allows an application to determine whether
 *          the link \p name in the group or file specified with \p loc_id
 *          resolves to an HDF5 object to open or if the link dangles. The
 *          link may be of any type, but hard links will always resolve
 *          to objects and do not need to be verified.
 *
 *          Note that H5Oexists_by_name() verifies only that the target
 *          object exists. If \p name includes either a relative path or
 *          an absolute path to the target link, intermediate steps
 *          along the path must be verified before the existence of
 *          the target link can be safely checked. If the path is not
 *          verified and an intermediate element of the path does not
 *          exist, H5Oexists_by_name() will fail. The example in the next
 *          paragraph illustrates one step-by-step method for verifying
 *          the existence of a link with a relative or absolute path.
 *
 * \par Example
 *          Use the following steps to verify the existence of
 *          the link \c datasetD in the \c group group1/group2/softlink_to_group3/,
 *          where \c group1 is a member of the group specified by \c loc_id:
 *
 * \par
 *      - First use H5Lexists() to verify that a link named \c group1 exists.
 *      - If \c group1 exists, use H5Oexists_by_name() to verify that the
 *        link \c group1 resolves to an object.
 *      - If \c group1 exists, use H5Lexists() again, this time with name
 *        set to \c group1/group2, to verify that the link \c group2 exists
 *        in \c group1.
 *      - If the \c group2 link exists, use H5Oexists_by_name() to verify
 *        that \c group1/group2 resolves to an object.
 *      - If \c group2 exists, use  H5Lexists() again, this time with name
 *        set to \c group1/group2/softlink_to_group3, to verify that the
 *        link \c softlink_to_group3 exists in \c group2.
 *      - If the \c softlink_to_group3 link exists, use H5Oexists_by_name()
 *        to verify that \c group1/group2/softlink_to_group3 resolves to
 *        an object.
 *      - If \c softlink_to_group3 exists, you can now safely use H5Lexists
 *        with name set to \c group1/group2/softlink_to_group3/datasetD to
 *        verify that the target link, \c datasetD, exists.
 *      - And finally, if the link \c datasetD exists, use H5Oexists_by_name
 *        to verify that \c group1/group2/softlink_to_group3/datasetD
 *        resolves to an object.
 *
 * \par
 *          If the link to be verified is specified with an absolute path,
 *          the same approach should be used, but starting with the first
 *          link in the file’s root group. For instance, if \c datasetD
 *          were in \c /group1/group2/softlink_to_group3, the first call to
 *          H5Lexists() would have name set to \c /group1.
 *
 * \par
 *          Note that this is an outline and does not include all necessary
 *          details. Depending on circumstances, for example, an application
 *          may need to verify the type of an object also.
 *
 * \warning \Bold{Failure Modes:}
 * \warning If \p loc_id and \p name both exist but the combination does not
 *          resolve to an object, the function will return 0 (zero);
 *          the function does not fail in this case.
 * \warning If either the location or the link specified by the \p loc_id
 *          and \p name combination does not exist, the function will fail,
 *          returning a negative value.
 * \warning Note that verifying the existence of an object within an HDF5
 *          file is a multistep process. An application can be certain the
 *          object does not exist only if H5Lexists()  and H5Oexists_by_name()
 *          have been used to verify the existence of the links and groups
 *          in the hierarchy above that object. The example above, in the
 *          function description, provides a step-by-step description of
 *          that verification process.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.5
 *
 */
H5_DLL htri_t H5Oexists_by_name(hid_t loc_id, const char *name, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object specified by an identifier
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 *
 * \return \herr_t
 *
 * \details H5Oget_info3() specifies an object by its identifier, \p loc_id , and
 *          retrieves the metadata describing that object in \p oinfo.
 *
 *          The \p fields parameter contains flags to determine which fields will be filled in
 *          the H5O_info2_t \c struct returned in \p oinfo.
 *          These flags are defined in the H5Opublic.h file:
 *
 *          \obj_info_fields
 *
 * \par Example
 *      An example snippet from examples/h5_attribute.c:
 * \par
 *      \snippet h5_attribute.c H5Oget_info3_snip
 *
 * \note If you are iterating through a lot of different objects to
 *       retrieve information via the H5Oget_info() family of routines,
 *       you may see memory building up. This can be due to memory
 *       allocation for metadata such as object headers and messages
 *       when the iterated objects are put into the metadata cache.
 * \note
 *       If the memory buildup is not desirable, you can configure a
 *       smaller cache via H5Fset_mdc_config() or set the file access
 *       property list via H5Pset_mdc_config(). A smaller sized cache
 *       will force metadata entries to be evicted from the cache,
 *       thus freeing the memory associated with the entries.
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_info3(hid_t loc_id, H5O_info2_t *oinfo, unsigned fields);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object by
 *        location and relative name
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of object, relative to \p loc_id
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Oget_info_by_name3() specifies an object’s location and name,
 *          \p loc_id and \p name, respectively, and retrieves the metadata
 *          describing that object in \p oinfo, an H5O_info2_t struct.
 *
 *          The \p fields parameter contains flags to determine which fields will be filled in
 *          the H5O_info2_t \c struct returned in \p oinfo.
 *          These flags are defined in the H5Opublic.h file:
 *
 *          \obj_info_fields
 *
 *          The link access property list, \c lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \par Example
 *      An example snippet from test/vol.c:
 *      \snippet vol.c H5Oget_info_by_name3_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_info_by_name3(hid_t loc_id, const char *name, H5O_info2_t *oinfo, unsigned fields,
                                   hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object
 *        by an index position
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] group_name Name of group in which object is located
 * \idx_type
 * \order
 * \param[in] n Position within the index
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Oget_info_by_idx3() retrieves the metadata describing an
 *          object in the \c struct \p oinfo, as specified by the location,
 *          \p loc_id, group name, \p group_name, the index by which objects
 *          in that group are tracked, \p idx_type, the order by which the
 *          index is to be traversed, \p order, and an object’s position
 *          \p n within that index.
 *
 *          If \p loc_id fully specifies the group in which the object resides,
 *          \p group_name can be a dot (\c .).
 *
 *          The \p fields parameter contains flags to determine which fields will be filled in
 *          the H5O_info2_t \c struct returned in \p oinfo.
 *          These flags are defined in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          The link access property list, \c lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \par Example
 *      An example snippet from test/titerate.c:
 *      \snippet titerate.c H5Oget_info_by_idx3_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_info_by_idx3(hid_t loc_id, const char *group_name, H5_index_t idx_type,
                                  H5_iter_order_t order, hsize_t n, H5O_info2_t *oinfo, unsigned fields,
                                  hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieve native file format information about an object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[out] oinfo Buffer in which to return native object information
 * \param[in] fields Flags to determine which fields in \p oinfo are filled in
 *
 * \return \herr_t
 *
 * \details H5Oget_native_info() retrieves the native file format information for an object
 *          specified by \p loc_id.
 *
 *          The \p fields parameter indicates which fields to fill in
 *          H5O_native_info_t. Possible values defined in H5Opublic.h are:
 *
 *          \snippet this H5O_native_info_fields_snip
 *
 * \par Example
 *      An example snippet from test/tfile.c:
 * \par
 *      \snippet tfile.c H5Oget_native_info_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_native_info(hid_t loc_id, H5O_native_info_t *oinfo, unsigned fields);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieve native file format information about an object given its name
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of object
 * \param[out] oinfo Buffer in which to return native object information
 * \param[in] fields Flags to determine which fields in \p oinfo are filled in
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Oget_native_info_by_name() retrieves the native file format
 *          information for an object specified by \p loc_id and the name \p
 *          name.
 *
 *          The \p fields parameter which fields to fill in H5O_native_info_t.
 *          Possible values defined in H5Opublic.h are:
 *
 *          \snippet this H5O_native_info_fields_snip
 *
 * \par Example
 *      An example snippet from test/tfile.c:
 *      \snippet tfile.c H5Oget_native_info_by_name_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_native_info_by_name(hid_t loc_id, const char *name, H5O_native_info_t *oinfo,
                                         unsigned fields, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieve native file format information about an object
 *        according to the order of an index
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] group_name Name of group in which object is located
 * \idx_type
 * \order
 * \param[in] n Position within the index
 * \param[out] oinfo Buffer in which to return native object information
 * \param[in] fields Flags to determine which fields in \p oinfo are filled in
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Oget_native_info_by_idx() retrieves the native file format information for an object
 *          specified by \p loc_id, group name, \p group_name, the index by which
 *          objects in the group are tracked, \p idx_type, the order by which
 *          the index is to be traversed, \p order , and an object's position
 *          \p n within that index.
 *
 *          The \p fields parameter indicates which fields to fill in H5O_native_info_t.
 *          Possible values defined in H5Opublic.h are:
 *          \snippet this H5O_native_info_fields_snip
 *
 *          The link access property list, \c lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Oget_native_info_by_idx(hid_t loc_id, const char *group_name, H5_index_t idx_type,
                                        H5_iter_order_t order, hsize_t n, H5O_native_info_t *oinfo,
                                        unsigned fields, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Creates a hard link to an object in an HDF5 file
 *
 * \param[in] obj_id Object to be linked
 * \param[in] new_loc_id Location identifier at which object is to be linked;
 *                       may be a file, group, dataset, named datatype or attribute identifier.
 * \param[in] new_name Name of link to be created, relative to \p new_loc_id.
 * \lcpl_id
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Olink() creates a new hard link to an object in an HDF5 file.
 *          \p new_loc_id and \p \p new_link_name specify the location and name of the
 *          new link while \p object_id identifies the object that the link
 *          points to.
 *
 *          H5Olink() is designed for two purposes:
 *          - To create the first hard link to an object that has just
 *            been created with H5Dcreate_anon(), H5Gcreate_anon(), or
 *            H5Tcommit_anon().
 *          - To add additional structure to an existing
 *            file so that, for example, an object can be shared among
 *            multiple groups.
 *
 *          \p lcpl and \p lapl are the link creation and access property lists
 *          associated with the new link.
 *
 * \par Example:
 *      To create a new link to an object while simultaneously creating
 *      missing intermediate groups: Suppose that an application must
 *      create the group C with the path /A/B01/C but may not know
 *      at run time whether the groups A and B01 exist. The following
 *      code ensures that those groups are created if they are missing:
 * \par
 * \code
 *
 *      // Creates a link creation property list (LCPL).
 *      hid_t lcpl_id = H5Pcreate(H5P_LINK_CREATE);
 *
 *      // Sets "create missing intermediate groups" property in that LCPL.
 *      int status = H5Pset_create_intermediate_group(lcpl_id, TRUE);
 *
 *      // Creates a group without linking it into the file structure.
 *      hid_t gid  = H5Gcreate_anon(file_id, H5P_DEFAULT, H5P_DEFAULT);
 *
 *      // Links group into file structure.
 *      status = H5Olink(gid, file_id, "/A/B01/C", lcpl_id, H5P_DEFAULT);
 *
 * \endcode
 *
 * \par
 *      Note that unless the object is intended to be temporary,
 *      the H5O_LINK call is mandatory if an object created with one
 *      of the H5*_CREATE_ANON functions (or with H5T_COMMIT_ANON)
 *      is to be retained in the file; without an H5O_LINK call,
 *      the object will not be linked into the HDF5 file structure
 *      and will be deleted when the file is closed.
 *
 * \version 1.8.1 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Olink(hid_t obj_id, hid_t new_loc_id, const char *new_name, hid_t lcpl_id, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Increments an object reference count
 *
 * \fgdta_loc_obj_id{object_id}
 *
 * \return \herr_t
 *
 * \details H5Oincr_refcount() increments the hard link reference count for an object.
 *          It should be used any time a user-defined link that references
 *          an object by address is added. When the link is deleted,
 *          H5Odecr_refcount() should be used.
 *
 *          An object’s reference count is the number of hard links in the
 *          file that point to that object. See the “Programming Model”
 *          section of the HDF5 Groups chapter in the -- <em>\ref UG</em>
 *          for a more complete discussion of reference counts.
 *
 *          If a user application needs to determine an object’s reference
 *          count, an H5Oget_info() call is required; the reference count
 *          is returned in the \c rc field of the #H5O_info_t \c struct.
 *
 * \warning This function must be used with care!
 * \warning Improper use can lead to inaccessible data, wasted space in the file,
 *          or <b><em>file corruption</em></b>.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oincr_refcount(hid_t object_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Decrements an object reference count
 *
 * \fgdta_loc_obj_id{object_id}
 *
 * \return \herr_t
 *
 * \details H5Odecr_refcount() decrements the hard link reference count for an object.
 *          It should be used any time a user-defined link that references
 *          an object by address is deleted. In general, H5Oincr_refcount() will have
 *          been used previously, when the link was created.
 *
 *          An object’s reference count is the number of hard links in the
 *          file that point to that object. See the “Programming Model”
 *          section of the HDF5 Groups chapter in the <em>\ref UG</em>
 *          for a more complete discussion of reference counts.
 *
 *          If a user application needs to determine an object’s reference
 *          count, an H5Oget_info() call is required; the reference count
 *          is returned in the \c rc field of the #H5O_info_t \c struct.
 *
 * \warning This function must be used with care!
 * \warning Improper use can lead to inaccessible data, wasted space in the file,
 *          or <b><em>file corruption</em></b>.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Odecr_refcount(hid_t object_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Copies an object in an HDF5 file
 *
 * \param[in] src_loc_id Object identifier indicating the location of the
 *                       source object to be copied
 * \param[in] src_name Name of the source object to be copied
 * \param[in] dst_loc_id Location identifier specifying the destination
 * \param[in] dst_name Name to be assigned to the new copy
 * \param[in] ocpypl_id Object copy property list
 * \lcpl_id
 *
 * \return \herr_t
 *
 * \details H5Ocopy() copies the group, dataset or committed datatype
 *          specified by \p src_name from the file or group specified by
 *          \p src_loc_id to the destination location \p dst_loc_id.
 *
 *          The destination location, as specified in dst_loc_id, may
 *          be a group in the current file or a location in a different
 *          file. If dst_loc_id is a file identifier, the copy will be
 *          placed in that file’s root group.
 *
 *          The copy will be created with the path specified in \p dst_name,
 *          which must not pre-exist in the destination location. If
 *          \p dst_name already exists at the location \p dst_loc_id,
 *          H5Ocopy() will fail. If \p dst_name is an absolute path,
 *          the copy will be created relative to the file’s root group.
 *
 *          The copy of the object is created with the property lists
 *          specified by \p ocpypl_id and \p lcpl_id. #H5P_DEFAULT can be passed
 *          in for these property lists. The default behavior:
 *
 *          - of the link creation property list is to NOT create
 *             intermediate groups.
 *          - of the flags specified by the object creation property list
 *            is described in H5Pset_copy_object().
 *
 *          These property lists or flags can be modified to govern the
 *          behavior of H5Ocopy() as follows:
 *
 *          - A flag controlling the creation of intermediate groups that
 *              may not yet exist is set in the link creation property list
 *              \p lcpl_id with H5Pset_create_intermediate_group().
 *
 *          - Copying of committed datatypes can be tuned through the use
 *              of H5Pset_copy_object(), H5Padd_merge_committed_dtype_path(),
 *              H5Pset_mcdt_search_cb(), and related functions.
 *
 *          - Flags controlling other aspects of object copying are set in the
 *              object copy property list \p ocpypl_id with H5Pset_copy_object().
 *
 *          H5Ocopy() will always try to make a copy of the object specified
 *          in \p src_name.
 *
 *          - If the object specified by \p src_name is a group containing a
 *              soft or external link, the default is that the new copy will
 *              contain a soft or external link with the same value as the
 *              original. See H5Pset_copy_object() for optional settings.
 *
 *          - If the path specified in \p src_name is or contains a soft link
 *              or an external link, H5Ocopy() will copy the target object.
 *              Use H5Lcopy() if the intent is to create a new soft or external
 *              link with the same value as the original link.
 *
 *          H5Ocopy() can be used to copy an object in an HDF5 file. If
 *          an object has been changed since it was opened, it should be
 *          written back to the file before using H5Ocopy(). The object
 *          can be written back either by closing the object (H5Gclose(),
 *          H5Oclose(), H5Dclose(), or H5Tclose()) or by flushing
 *          the HDF5 file (H5Fflush()).
 *
 * \par See Also:
 *      - Functions to modify the behavior of H5Ocopy():
 *          - H5Padd_merge_committed_dtype_path()
 *          - H5Pset_copy_object()
 *          - H5Pset_create_intermediate_group()
 *          - H5Pset_mcdt_search_cb()
 *      - Copying Committed Datatypes with #H5Ocopy - A comprehensive
 *        discussion of copying committed datatypes (PDF) in
 *        Advanced Topics in HDF5
 *
 * \version 1.8.9 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Ocopy(hid_t src_loc_id, const char *src_name, hid_t dst_loc_id, const char *dst_name,
                      hid_t ocpypl_id, hid_t lcpl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Sets comment for specified object
 *
 * \fgdta_loc_obj_id{obj_id}
 * \param[in] comment The new comment
 *
 * \return \herr_t
 *
 * \details H5Oset_comment() sets the comment for the specified object
 *          to the contents of \p comment. Any previously existing comment
 *          is overwritten.
 *
 *          The target object is specified by an identifier, \p obj_id.
 *          If \p comment is the empty string or a null pointer, any existing
 *          comment message is removed from the object.
 *
 *          Comments should be relatively short, null-terminated, ASCII strings.
 *
 *          Comments can be attached to any object that has an object
 *          header. Datasets, groups, and committed (named) datatypes have
 *          object headers. Symbolic links do not have object headers.
 *
 *          If a comment is being added to an object attribute, this comment
 *          will be attached to the object to which the attribute belongs
 *          and not to the attribute itself.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oset_comment(hid_t obj_id, const char *comment);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Sets comment for specified object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of the object whose comment is to be set or reset
 * \param[in] comment The new comment
 * \lapl_id
 *
 * \return \herr_t
 *
 * \details H5Oset_comment_by_name() sets the comment for the specified object
 *          to the contents of \p comment. Any previously existing comment
 *          is overwritten.
 *
 *          The target object is specified by \p loc_id and \p name.
 *          \p loc_id can specify any object in the file.
 *          \p name can be one of the following:
 *
 *          - The name of the object specified as a path relative to \p loc_id
 *          - An absolute name of the object, starting from \c /, the file’s root group
 *          - A dot (\c .), if \p loc_id fully specifies the object
 *
 *          If \p comment is the empty string or a null pointer, any existing
 *          comment message is removed from the object.
 *
 *          Comments should be relatively short, null-terminated, ASCII strings.
 *
 *          Comments can be attached to any object that has an object
 *          header. Datasets, groups, and committed (named) datatypes have
 *          object headers. Symbolic links do not have object headers.
 *
 *          If a comment is being added to an object attribute, this comment
 *          will be attached to the object to which the attribute belongs
 *          and not to the attribute itself.
 *
 *          \p lapl_id contains a link access property list identifier. A
 *          link access property list can come into play when traversing
 *          links to access an object.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oset_comment_by_name(hid_t loc_id, const char *name, const char *comment, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves comment for specified object
 *
 * \fgdta_loc_obj_id{obj_id}
 * \param[out] comment The comment
 * \param[in] bufsize Anticipated required size of the comment buffer
 *
 * \return Upon success, returns the number of characters in the
 *         comment, not including the \c NULL terminator, or zero (\c 0) if
 *         the object has no comment. The value returned may be larger
 *         than \p bufsize. Otherwise returns a negative value.
 *
 * \details H5Oget_comment() retrieves the comment for the specified object in
 *          the buffer \p comment.
 *
 *          The target object is specified by an identifier, \p object_id.
 *
 *          The size in bytes of the buffer \p comment, including the \c NULL
 *          terminator, is specified in \p bufsize. If \p bufsize is unknown,
 *          a preliminary H5Oget_comment() call with the pointer \p comment
 *          set to \c NULL will return the size of the comment <em>without</em>
 *          the \c NULL terminator.
 *
 *          If \p bufsize is set to a smaller value than described above,
 *          only \p bufsize bytes of the comment, without a \c NULL terminator,
 *          are returned in \p comment.
 *
 *          If an object does not have a comment, the empty string is
 *          returned in \p comment.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL ssize_t H5Oget_comment(hid_t obj_id, char *comment, size_t bufsize);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves comment for specified object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of the object whose comment is to be retrieved
 * \param[out] comment The comment
 * \param[in] bufsize Anticipated required size of the \p comment buffer
 * \lapl_id
 *
 * \return Upon success, returns the number of characters in the comment,
 *         not including the \c NULL terminator, or zero (\c 0) if the object
 *         has no comment. The value returned may be larger than \c bufsize.
 *         Otherwise returns a negative value.
 *
 * \details H5Oget_comment_by_name() retrieves the comment for an object
 *          in the buffer \p comment.
 *
 *          The target object is specified by \p loc_id and \p name.
 *          \p loc_id can specify any object in the file.
 *          \p name can be one of the following:
 *
 *          - The name of the object relative to \p loc_id
 *          - An absolute name of the object, starting from \c /, the file’s root group
 *          - A dot (\c .), if \p loc_id fully specifies the object
 *
 *          The size in bytes of the comment, including the \c NULL terminator,
 *          is specified in \p bufsize. If \p bufsize is unknown, a preliminary
 *          H5Oget_comment_by_name() call with the pointer \p comment set
 *          to \c NULL will return the size of the comment <em>without</em>
 *          the \c NULL terminator.
 *
 *          If \p bufsize is set to a smaller value than described above,
 *          only \p bufsize bytes of the comment, without a \c NULL terminator,
 *          are returned in \p comment.
 *
 *          If an object does not have a comment, the empty string is
 *          returned in \p comment.
 *
 *          \p lapl_id contains a link access property list identifier. A
 *          link access property list can come into play when traversing
 *          links to access an object.
 *
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL ssize_t H5Oget_comment_by_name(hid_t loc_id, const char *name, char *comment, size_t bufsize,
                                      hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects accessible from a specified object
 *
 * \fgdta_loc_obj_id{obj_id}
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 * \param[in] fields Flags specifying the fields to be retrieved to the
 *                   callback \p op
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \details H5Ovisit3() is a recursive iteration function to visit the
 *          object \p obj_id and, if \p obj_id is a group, all objects in
 *          and below it in an HDF5 file, thus providing a mechanism for
 *          an application to perform a common set of operations across
 *          all of those objects or a dynamically selected subset.
 *          For non-recursive iteration across the members of a group,
 *          see H5Literate2().
 *
 *          If \p obj_id is a group identifier, that group serves as the
 *          root of a recursive iteration. If \p obj_id is a file identifier,
 *          that file’s root group serves as the root of the recursive
 *          iteration.  If \p obj_id is an attribute identifier,
 *          then the object where the attribute is attached will be iterated.
 *          If \p obj_id is any other type of object, such as a dataset or
 *          named datatype, there is no iteration.
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.

 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in
 *          a value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          The H5Ovisit3() \p op_data parameter is a user-defined pointer to the data
 *          required to process objects in the course of the iteration. This pointer
 *          is passed back to each step of the iteration in the callback
 *          function’s \p op_data parameter.
 *
 *          The \p fields parameter contains flags to determine which fields will
 *          be retrieved by the \p op callback function. These flags are defined
 *          in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          H5Lvisit2() and H5Ovisit3() are companion functions: one for
 *          examining and operating on links; the other for examining
 *          and operating on the objects that those links point to. Both
 *          functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires. These functions assume
 *          that the membership of the group being iterated over remains
 *          unchanged through the iteration; if any of the links in the
 *          group change during the iteration, the resulting behavior
 *          is undefined.
 *
 * \par Example
 *      An example snippet from test/links.c:
 *      \snippet links.c H5Ovisit3_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Ovisit3(hid_t obj_id, H5_index_t idx_type, H5_iter_order_t order, H5O_iterate2_t op,
                        void *op_data, unsigned fields);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects accessible from a specified object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] obj_name Name of the object, generally relative to
 *                     \p loc_id, that will serve as root of the iteration
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 * \param[in] fields Flags specifying the fields to be retrieved to the
 *                   callback function \p op
 * \lapl_id
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \details H5Ovisit_by_name3() is a recursive iteration function to visit
 *          the object specified by the \p loc_id / \p obj_name parameter
 *          pair and, if that object is a group, all objects in and below it
 *          in an HDF5 file, thus providing a mechanism for an application to
 *          perform a common set of operations across all of those objects or
 *          a dynamically selected subset. For non-recursive iteration across
 *          the members of a group, see H5Literate2().
 *
 *          The object serving as the root of the iteration is specified
 *          by the \p loc_id / \p obj_name parameter pair. \p loc_id specifies
 *          a file or an object in a file;  if \p loc_id is an attribute identifier,
 *          the object where the attribute is attached will be used.
 *          \p obj_name specifies either an object in the file (with an absolute
 *          name based in the file’s root group) or an object name relative
 *          to \p loc_id. If \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, \p obj_name should be '\c .' (a dot).
 *          (Note that when \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, the user may wish to consider
 *          using H5Ovisit3() instead of H5Ovisit_by_name3().)
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.
 *
 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in a
 *          value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          The H5Ovisit_by_name3() \p op_data parameter is a user-defined
 *          pointer to the data required to process objects in the course
 *          of the iteration. This pointer is passed back to each step of
 *          the iteration in the callback function’s \p op_data parameter.
 *
 *          \p lapl_id is a link access property list. In the general case,
 *          when default link access properties are acceptable, this can
 *          be passed in as #H5P_DEFAULT. An example of a situation that
 *          requires a non-default link access property list is when
 *          the link is an external link; an external link may require
 *          that a link prefix be set in a link access property list
 *          (see H5Pset_elink_prefix()).
 *
 *          The \p fields parameter contains flags to determine which fields will
 *          be retrieved by the \p op callback function. These flags are defined
 *          in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          H5Lvisit_by_name2() and H5Ovisit_by_name3() are companion
 *          functions: one for examining and operating on links; the other
 *          for examining and operating on the objects that those links point to.
 *          Both functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires.
 *
 * \par Example
 *      An example snippet from test/links.c:
 *      \snippet links.c H5Ovisit_by_name3_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Ovisit_by_name3(hid_t loc_id, const char *obj_name, H5_index_t idx_type,
                                H5_iter_order_t order, H5O_iterate2_t op, void *op_data, unsigned fields,
                                hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Closes an object in an HDF5 file
 *
 * \obj_id{object_id}
 *
 * \return \herr_t
 *
 * \details H5Oclose() closes the group, dataset, or named datatype specified by
 *          object_id.
 *
 *          This function is the companion to H5Oopen(), and has the same
 *          effect as calling H5Gclose(), H5Dclose(), or H5Tclose().
 *
 *          H5Oclose() is not used to close a dataspace, attribute, property
 *          list, or file.
 *
 * \version 1.8.8 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oclose(hid_t object_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Flushes all buffers associated with an HDF5 object to disk
 *
 * \fgdta_loc_obj_id{obj_id}
 *
 * \return \herr_t
 *
 * \details H5Oflush() causes all buffers associated with an object to be immediately
 *          flushed to disk without removing the data from the cache.
 *
 *          The object associated with \p object_id can be any named object in an
 *          HDF5 file including a dataset, a group, or a committed datatype.
 *
 * \note HDF5 does not possess full control over buffering. H5Oflush()
 *       flushes the internal HDF5 buffers and then asks the operating
 *       system (the OS) to flush the system buffers for the open
 *       files. After that, the OS is responsible for ensuring that
 *       the data is actually flushed to disk.
 *
 * \see H5Dflush(), H5Drefresh(), H5Oflush(), H5Grefresh(), H5Oflush(),
 *      H5Orefresh(), H5Tflush(), H5Trefresh()
 * \see H5DOappend(), H5Fstart_swmr_write(), H5Pget_append_flush(),
 *      H5Pget_object_flush_cb(), H5Pset_append_flush(), H5Pset_object_flush_cb()
 * \see H5Oare_mdc_flushes_disabled(), H5Odisable_mdc_flushes(), H5Oenable_mdc_flushes()
 *
 * \since 1.10.0
 *
 */
H5_DLL herr_t H5Oflush(hid_t obj_id);
/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Refreshes all buffers associated with an HDF5 object
 *
 * \fgdta_loc_obj_id{oid}
 *
 * \return \herr_t
 *
 * \details H5Orefresh() causes all buffers associated with an object to be cleared
 *          and immediately re-loaded with updated contents from disk.
 *
 *          This function essentially closes the object, evicts all
 *          metadata associated with it from the cache, and then re-opens
 *          the object. The reopened object is automatically re-registered
 *          with the same identifier.
 *
 *          The object associated with \p oid can be any named object in an
 *          HDF5 file including a dataset, a group, or a committed datatype.
 *
 * \since 1.10.0
 *
 */
H5_DLL herr_t H5Orefresh(hid_t oid);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Prevents metadata entries for an HDF5 object from being flushed
 *        from the metadata cache to storage
 *
 * \param[in] object_id Identifier of the object that will have flushes disabled;
 *                      may be a group, named datatype, or dataset identifier
 *
 * \return \herr_t
 *
 * \details H5Odisable_mdc_flushes(), H5Oenable_mdc_flushes() and associated flush
 *          functions can be used to control the flushing of entries from
 *          a file’s metadata cache.
 *
 *          This function prevents an object’s or cache’s dirty metadata
 *          entries from being flushed from the cache by the usual cache
 *          eviction/flush policy. Instead, users must manually flush the
 *          cache or entries for individual objects via the appropriate
 *          H5Fflush(), H5Dflush(), H5Gflush(), H5Tflush(), and H5Oflush() calls.
 *
 *          Metadata cache entries can be controlled at both the individual
 *          HDF5 object level (datasets, groups, committed datatypes)
 *          and the entire metadata cache level.
 *
 * \note HDF5 objects include datasets, groups, and committed datatypes.  Only
 *       #hid_t identifiers that represent these objects can be passed to the
 *       function.  Passing in a #hid_t identifier that represents any other
 *       HDF5 entity is considered an error.  It is an error to pass an HDF5
 *       file identifier (obtained from H5Fopen() or H5Fcreate()) to this
 *       function.  Misuse of this function can cause the cache to exhaust
 *       available memory.  Objects can be returned to the default automatic
 *       flush behavior with H5Oenable_mdc_flushes().  Flush prevention only
 *       pertains to new or dirty metadata entries.  Clean entries can be
 *       evicted from the cache.  Calling this function on an object that has
 *       already had flushes disabled will return an error.
 *
 * \since 1.10.0
 *
 */
H5_DLL herr_t H5Odisable_mdc_flushes(hid_t object_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Enables flushing of dirty metadata entries from a file’s metadata cache
 *
 * \param[in] object_id Identifier of the object that will have flushes re-enabled;
 *                      may be a group, named datatype, or dataset identifier
 *
 * \return \herr_t
 *
 * \details H5Oenable_mdc_flushes(), H5Odisable_mdc_flushes()
 *          and associated flush functions can be used to control the flushing
 *          of entries from a file’s metadata cache.
 *
 *          This function allows an object or cache’s dirty metadata entries to be
 *          flushed from the cache by the usual cache eviction/flush policy.
 *
 *          Metadata cache entries can be controlled at both the individual HDF5
 *          object level (datasets, groups, committed datatypes) and the entire
 *          metadata cache level.
 *
 *
 * \note HDF5 objects include datasets, groups, and committed datatypes.  Only
 *       #hid_t identifiers that represent these objects can be passed to the
 *       function.  Passing in a #hid_t identifier that represents any other
 *       HDF5 entity is considered an error.  It is an error to pass an HDF5
 *       file identifier (obtained from H5Fopen() or H5Fcreate()) to this
 *       function.  Using this function on an object that has not had flushes
 *       disabled is considered an error. The state of an object can be
 *       determined with H5Oare_mdc_flushes_disabled().  An object will be
 *       returned to the default flush algorithm when it is closed.  All objects
 *       will be returned to the default flush algorithm when the file is
 *       closed.  An object’s entries will not necessarily be flushed as a
 *       result of calling this function.
 *
 * \since 1.10.0
 *
 */
H5_DLL herr_t H5Oenable_mdc_flushes(hid_t object_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves comment for specified object
 *
 * \param[in] object_id Identifier of an object in the cache;
 *                      may be a group, named datatype, or dataset identifier
 * \param[out] are_disabled Flushes enabled/disabled
 *
 * \return \p are_disabled will be set to \c 1 if an object has had flushes disabled
 *            and \c 0 if it has not had flushes disabled.
 * \return \herr_t
 *
 * \details H5Oare_mdc_flushes_disabled() determines if an HDF5 object (dataset, group, committed
 *          datatype) has had flushes of metadata entries disabled.
 *
 *          The H5Oenable_mdc_flushes(), H5Odisable_mdc_flushes() and
 *          associated flush functions can be used to control the flushing of
 *          entries from a file’s metadata cache. Metadata cache entries can be controlled
 *          at both the individual HDF5 object level (datasets, groups,
 *          committed datatypes) and the entire metadata cache level.
 *
 * \note HDF5 objects include datasets, groups, and committed datatypes.
 *       Only #hid_t identifiers that represent these objects can be passed to the function.
 * \note Passing in a #hid_t identifier that represents any other HDF5 entity is
 *       considered an error.
 * \note It is an error to pass an HDF5 file identifier
 *       (obtained from H5Fopen() or H5Fcreate()) to this function.
 *
 * \since 1.10.0
 *
 */
H5_DLL herr_t H5Oare_mdc_flushes_disabled(hid_t object_id, hbool_t *are_disabled);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Compares two VOL connector object tokens
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] token1 First object token
 * \param[in] token2 Second object token
 * \param[out] cmp_value Comparison value
 *
 * \return \herr_t
 *
 * \details H5Otoken_cmp() compares two VOL connector object tokens, \p token1
 *          and \p token2 for the file or group identifier specified by \p loc_id.
 *          Both object tokens must be from the same VOL connector class.
 *
 *          H5O_token_t is defined in H5public.h as follows:
 *          \snippet H5public.h H5O_token_t_snip
 *
 *          A comparison value, \p cmp_value, is returned, which indicates the
 *          result of the comparison:
 *
 * <table>
 *  <tr>
 *      <th>cmp_value</th>
 *      <th>Result</th>
 * </tr>
 *  <tr>
 *      <td> > 0</td>
 *      <td> \p token1 > \p token2</td>
 *  </tr>
 *  <tr>
 *      <td> < 0</td>
 *      <td>\p token1 < \p token2</td>
 *  </tr>
 *  <tr>
 *      <td>0</td>
 *      <td>\p token1 = \p token2</td>
 *  </tr>
 * </table>
 *
 * \par Example
 *      An example snippet from test/links.c:
 *      \snippet links.c H5Otoken_cmp_snip
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Otoken_cmp(hid_t loc_id, const H5O_token_t *token1, const H5O_token_t *token2,
                           int *cmp_value);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Serializes a connector's object token into a string
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] token Connector object token
 * \param[out] token_str String for connector object token \p token
 *
 * \return \herr_t
 *
 * \details H5Otoken_to_str() serializes a connector's object token specified by
 *          \p token and the location identifier for the object, \p loc_id,
 *          into a string, \p token_str.
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Otoken_to_str(hid_t loc_id, const H5O_token_t *token, char **token_str);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Deserializes a string into a connector object token
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] token_str Object token string
 * \param[out] token Connector object token
 *
 * \return \herr_t
 *
 * \details H5Otoken_from_str() deserializes a string, \p token_str, into a
 *          connector object token, \p token, for the object specified by the
 *          location identifier, \p loc_id.
 *
 * \since 1.12.0
 *
 */
H5_DLL herr_t H5Otoken_from_str(hid_t loc_id, const char *token_str, H5O_token_t *token);

/* The canonical 'undefined' token value */
#define H5O_TOKEN_UNDEF (H5OPEN H5O_TOKEN_UNDEF_g)
H5_DLLVAR const H5O_token_t H5O_TOKEN_UNDEF_g;

/* Symbols defined for compatibility with previous versions of the HDF5 API.
 *
 * Use of these symbols is deprecated.
 */
#ifndef H5_NO_DEPRECATED_SYMBOLS

/* Macros */

/* Deprecated flags for earlier versions of H5Oget_info* */
#define H5O_INFO_HDR       0x0008u /**< Fill in the hdr field */
#define H5O_INFO_META_SIZE 0x0010u /**< Fill in the meta_size field */
#undef H5O_INFO_ALL
#define H5O_INFO_ALL (H5O_INFO_BASIC | H5O_INFO_TIME | H5O_INFO_NUM_ATTRS | H5O_INFO_HDR | H5O_INFO_META_SIZE)

/* Typedefs */

//! <!-- [H5O_stat_t_snip] -->
/**
 * A struct that's part of the \ref H5G_stat_t structure
 * \deprecated
 */
typedef struct H5O_stat_t {
    hsize_t  size;    /**< Total size of object header in file */
    hsize_t  free;    /**< Free space within object header */
    unsigned nmesgs;  /**< Number of object header messages */
    unsigned nchunks; /**< Number of object header chunks */
} H5O_stat_t;
//! <!-- [H5O_stat_t_snip] -->

//! <!-- [H5O_info1_t_snip] -->
/**
 * Information struct for object (For H5Oget_info(), H5Oget_info_by_name(),
 * H5Oget_info_by_idx() versions 1 & 2.)
 */
typedef struct H5O_info1_t {
    unsigned long  fileno;    /**< File number that object is located in */
    haddr_t        addr;      /**< Object address in file                */
    H5O_type_t     type;      /**< Basic object type (group, dataset, etc.) */
    unsigned       rc;        /**< Reference count of object    */
    time_t         atime;     /**< Access time                  */
    time_t         mtime;     /**< Modification time            */
    time_t         ctime;     /**< Change time                  */
    time_t         btime;     /**< Birth time                   */
    hsize_t        num_attrs; /**< Number of attributes attached to object */
    H5O_hdr_info_t hdr;       /**< Object header information */
    /* Extra metadata storage for obj & attributes */
    struct {
        H5_ih_info_t obj;  /**< v1/v2 B-tree & local/fractal heap for groups, B-tree for chunked datasets */
        H5_ih_info_t attr; /**< v2 B-tree & heap for attributes */
    } meta_size;
} H5O_info1_t;
//! <!-- [H5O_info1_t_snip] -->

//! <!-- [H5O_iterate1_t_snip] -->
/**
 * Prototype for H5Ovisit(), H5Ovisit_by_name() operator (versions 1 & 2)
 *
 * \param[in] obj Object that serves as the root of the iteration;
 *                the same value as the H5Ovisit1() \c obj_id parameter
 * \param[in] name Name of object, relative to \p obj, being examined at current
 *                 step of the iteration
 * \param[out] info Information about that object
 * \param[in,out] op_data User-defined pointer to data required by the application
 *                        in processing the object
 * \return \herr_t_iter
 *
 */
typedef herr_t (*H5O_iterate1_t)(hid_t obj, const char *name, const H5O_info1_t *info, void *op_data);
//! <!-- [H5O_iterate1_t_snip] -->

/* Function prototypes */

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Opens an object using its address within an HDF5 file.
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] addr Object's address in the file
 *
 * \return \hid_tv{object}
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oopen_by_token().
 *
 * \details H5Oopen_by_addr() opens a group, dataset, or committed (named) datatype using its
 *          address within an HDF5 file, \p addr. The resulting opened object is identical to
 *          an object opened with H5Oopen() and should be closed with H5Oclose() or an
 *          object-type-specific closing function (such as H5Gclose()) when no longer needed.
 *
 *          \p loc_id is a location identifier in the file.
 *
 *          The object’s address within the file, \p addr, is the byte offset of the first byte
 *          of the object header from the beginning of the HDF5 file space, i.e., from the
 *          beginning of the super block (see the “HDF5 Storage Model” section of the The
 *          HDF5 Data Model and File Structure chapter of the <em>HDF5 User's Guide</em>.)
 *
 *          \p addr can be obtained via either of two function calls. H5Gget_objinfo() returns
 *          the object’s address in the \c objno field of the H5G_stat_t \c struct;
 *          H5Lget_info() returns the address in the \c address field of the #H5L_info_t \c struct.
 *
 *          The address of the HDF5 file on a physical device has no effect on H5Oopen_by_addr(),
 *          nor does the use of any file driver. As stated above, the object address is its
 *          offset within the HDF5 file; HDF5’s file drivers will transparently map this to an
 *          address on a storage device.
 *
 * \warning This function must be used with care!
 * \warning Improper use can lead to inaccessible data, wasted space in the file,
 *          or <b><em>file corruption</em></b>.
 * \warning This function is dangerous if called on an invalid address. The risk can be safely
 *          overcome by retrieving the object address with H5Gget_objinfo() or H5Lget_info()
 *          immediately before calling H5Oopen_by_addr(). The immediacy of the operation can be
 *          important; if time has elapsed and the object has been deleted from the file,
 *          the address will be invalid and file corruption can result.
 *
 * \version 1.8.4 Fortran subroutine added in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL hid_t H5Oopen_by_addr(hid_t loc_id, haddr_t addr);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object specified by an identifier
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[out] oinfo Buffer in which to return object information
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oget_info3() or the macro #H5Oget_info.
 *
 * \details H5Oget_info1() specifies an object by its identifier, \p loc_id , and
 *          retrieves the metadata describing that object in \p oinfo.
 *
 * \note If you are iterating through a lot of different objects to
 *       retrieve information via the H5Oget_info() family of routines,
 *       you may see memory building up. This can be due to memory
 *       allocation for metadata such as object headers and messages
 *       when the iterated objects are put into the metadata cache.
 * \note
 *       If the memory buildup is not desirable, you can configure a
 *       smaller cache via H5Fset_mdc_config() or set the file access
 *       property list via H5Pset_mdc_config(). A smaller sized cache
 *       will force metadata entries to be evicted from the cache,
 *       thus freeing the memory associated with the entries.
 *
 * \version 1.10.5 The macro #H5Oget_info was removed and the function
 *                 H5Oget_info1() was copied to H5Oget_info().
 * \version 1.10.3 Function H5Oget_info() was copied to H5Oget_info1(),
 *                 and the macro #H5Oget_info was created.
 * \version 1.8.15 Added a note about the valid values for the \c version
 *                 field in the H5O_hdr_info_t structure.
 * \version 1.8.11 Fortran subroutine introduced in this release.
 * \version 1.8.10 Added #H5O_type_t structure to the Description section. \n
 *                 Separated H5O_hdr_info_t structure from #H5O_info_t in the
 *                 Description section. \n
 *                 Clarified the definition and implementation of the time fields.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oget_info1(hid_t loc_id, H5O_info1_t *oinfo);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object
 *        by location and relative name
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of object, relative to \p loc_id
 * \param[out] oinfo Buffer in which to return object information
 * \lapl_id
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oget_info_by_name2() or the macro #H5Oget_info_by_name.
 *
 * \details H5Oget_info_by_name1() specifies an object’s location and name, \p loc_id
 *          and \p name, respectively, and retrieves the metadata describing that object
 *          in \p oinfo, an H5O_info1_t \c struct.
 *
 *          The \c struct H5O_info1_t is defined in H5Opublic.h and described
 *          in the H5Oget_info1() function entry.
 *
 *          The link access property list, \p lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \version 1.10.5 The macro #H5Oget_info_by_name was removed and the function
 *                 H5Oget_info_by_name1() was copied to H5Oget_info_by_name().
 * \version 1.10.3 Function H5Oget_info_by_name() was copied to H5Oget_info_by_name1()
 *                 and the macro #H5Oget_info_by_name was created.
 * \version 1.8.8 Fortran 2003 subroutine and \c h5o_info_t derived type introduced
 *                in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oget_info_by_name1(hid_t loc_id, const char *name, H5O_info1_t *oinfo, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object
 *        by an index position
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] group_name Name of group in which object is located
 * \idx_type
 * \order
 * \param[in] n Position within the index
 * \param[out] oinfo Buffer in which to return object information
 * \lapl_id
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oget_info_by_idx3() or the macro H5Oget_info_by_idx().
 *
 * \details H5Oget_info_by_idx1() retrieves the metadata describing an
 *          object in the \c struct \p oinfo, as specified by the location,
 *          \p loc_id, group name, \p group_name, the index by which objects
 *          in that group are tracked, \p idx_type, the order by which the
 *          index is to be traversed, \p order, and an object’s position
 *          \p n within that index.
 *
 *          If \p loc_id fully specifies the group in which the object resides,
 *          \p group_name can be a dot (\c .).
 *
 *          The link access property list, \c lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \version 1.10.5 The macro #H5Oget_info_by_idx was removed and the function
 *                 H5Oget_info_by_idx() was copied to H5Oget_info_by_idx1().
 * \version 1.10.3 Function H5Oget_info_by_idx() was copied to H5Oget_info_by_idx1()
 *                 and the macro #H5Oget_info_by_idx was created.
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Oget_info_by_idx1(hid_t loc_id, const char *group_name, H5_index_t idx_type,
                                  H5_iter_order_t order, hsize_t n, H5O_info1_t *oinfo, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object specified by an identifier
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oget_info3() or the macro H5Oget_info().
 *
 * \details H5Oget_info2() specifies an object by its identifier, \p loc_id , and
 *          retrieves the metadata describing that object in \p oinfo , an H5O_info1_t \c struct.
 *          This \c struct type is described in H5Oget_info1().
 *
 *          The \p fields parameter contains flags to determine which fields will be filled in
 *          the H5O_info1_t \c struct returned in \p oinfo.
 *          These flags are defined in the H5Opublic.h file:
 *
 *          \obj_info_fields
 *
 * \note If you are iterating through a lot of different objects to
 *       retrieve information via the H5Oget_info() family of routines,
 *       you may see memory building up. This can be due to memory
 *       allocation for metadata such as object headers and messages
 *       when the iterated objects are put into the metadata cache.
 * \note
 *       If the memory buildup is not desirable, you can configure a
 *       smaller cache via H5Fset_mdc_config() or set the file access
 *       property list via H5Pset_mdc_config(). A smaller sized cache
 *       will force metadata entries to be evicted from the cache,
 *       thus freeing the memory associated with the entries.
 *
 * \since 1.10.3
 *
 */
H5_DLL herr_t H5Oget_info2(hid_t loc_id, H5O_info1_t *oinfo, unsigned fields);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object
 *        by location and relative name
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] name Name of object, relative to \p loc_id
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 * \lapl_id
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Oget_info_by_name3() or the macro H5Oget_info_by_name().
 *
 * \details H5Oget_info_by_name2() specifies an object’s location and name, \p loc_id and
 *          \p name, respectively, and retrieves the metadata describing
 *          that object in \p oinfo, an H5O_info1_t \c struct.
 *
 *          The \c struct H5O_info1_t is defined in H5Opublic.h and described
 *          in the H5Oget_info1() function entry.
 *
 *          The \p fields parameter contains flags to determine which fields
 *          will be filled in the H5O_info1_t \c struct returned in
 *          \p oinfo. These flags are defined in the H5Opublic.h file:
 *
 *          \obj_info_fields
 *
 *          The link access property list, \p lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \since 1.10.3
 *
 */
H5_DLL herr_t H5Oget_info_by_name2(hid_t loc_id, const char *name, H5O_info1_t *oinfo, unsigned fields,
                                   hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Retrieves the metadata for an object, identifying the object
 *        by an index position
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] group_name Name of group in which object is located
 * \idx_type
 * \order
 * \param[in]  n Position within the index
 * \param[out] oinfo Buffer in which to return object information
 * \param[in] fields Flags specifying the fields to include in \p oinfo
 * \lapl_id
 *
 * \return \herr_t
 *
 * \deprecated As of HDF5-1.12 this function is deprecated in favor of
 *             the function H5Oget_info_by_idx3() or the macro #H5Oget_info_by_idx.
 *
 * \details H5Oget_info_by_idx2() retrieves the metadata describing an
 *          object in the \c struct \p oinfo, as specified by the location,
 *          \p loc_id, group name, \p group_name, the index by which objects
 *          in that group are tracked, \p idx_type, the order by which the
 *          index is to be traversed, \p order, and an object’s position
 *          \p n within that index.
 *
 *          \p oinfo, in which the object information is returned, is a \c struct of
 *          type H5O_info1_t.  This and other \c struct types used
 *          by H5Oget_info_by_idx2() are described in H5Oget_info_by_idx1().
 *
 *          If \p loc_id fully specifies the group in which the object resides,
 *          i\p group_name can be a dot (\c .).
 *
 *          The \p fields parameter contains flags to determine which fields will be
 *          filled in the H5O_info1_t \c struct returned in \p oinfo.
 *          These flags are defined in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          The link access property list, \c lapl_id, is not currently used;
 *          it should be passed in as #H5P_DEFAULT.
 *
 * \since 1.10.3
 *
 */
H5_DLL herr_t H5Oget_info_by_idx2(hid_t loc_id, const char *group_name, H5_index_t idx_type,
                                  H5_iter_order_t order, hsize_t n, H5O_info1_t *oinfo, unsigned fields,
                                  hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects accessible from a specified object
 *
 * \fgdta_loc_obj_id{obj_id}
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Ovisit3() or the macro #H5Ovisit.
 *
 * \details H5Ovisit1() is a recursive iteration function to visit the
 *          object \p obj_id and, if \p obj_id is a group, all objects in
 *          and below it in an HDF5 file, thus providing a mechanism for
 *          an application to perform a common set of operations across all
 *          of those objects or a dynamically selected subset. For
 *          non-recursive iteration across the members of a group,
 *          see  H5Literate1().
 *
 *          If \p obj_id is a group identifier, that group serves as the
 *          root of a recursive iteration. If \p obj_id is a file identifier,
 *          that file’s root group serves as the root of the recursive
 *          iteration.  If \p obj_id is an attribute identifier,
 *          then the object where the attribute is attached will be iterated.
 *          If \p obj_id is any other type of object, such as a dataset or
 *          named datatype, there is no iteration.
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.
 *
 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in
 *          a value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          H5Lvisit1() and H5Ovisit1() are companion functions: one for
 *          examining and operating on links; the other for examining
 *          and operating on the objects that those links point to. Both
 *          functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires. These functions assume
 *          that the membership of the group being iterated over remains
 *          unchanged through the iteration; if any of the links in the
 *          group change during the iteration, the resulting behavior
 *          is undefined.
 *
 * \version 1.10.5 The macro #H5Ovisit was removed and the function
 *          H5Ovisit1() was copied to H5Ovisit().
 * \version 1.10.3 Function H5Ovisit() was copied to H5Ovisit1(),
 *          and the macro #H5Ovisit was created.
 * \version 1.8.8 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Ovisit1(hid_t obj_id, H5_index_t idx_type, H5_iter_order_t order, H5O_iterate1_t op,
                        void *op_data);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects starting from a specified object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] obj_name Name of the object, generally relative to
 *                     \p loc_id, that will serve as root of the iteration
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 * \lapl_id
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Ovisit_by_name3() or the macro #H5Ovisit_by_name.
 *
 * \details H5Ovisit_by_name1() is a recursive iteration function to visit
 *          the object specified by the \p loc_id / \p obj_name parameter
 *          pair and, if that object is a group, all objects in and below it
 *          in an HDF5 file, thus providing a mechanism for an application to
 *          perform a common set of operations across all of those objects or
 *          a dynamically selected subset. For non-recursive iteration across
 *          the members of a group, see H5Literate1().
 *
 *          The object serving as the root of the iteration is specified
 *          by the \p loc_id / \p obj_name parameter pair. \p loc_id specifies
 *          a file or an object in a file;  if \p loc_id is an attribute identifier,
 *          the object where the attribute is attached will be used.
 *          \p obj_name specifies either an object in the file (with an absolute
 *          name based in the file’s root group) or an object name relative
 *          to \p loc_id. If \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, \p obj_name should be '\c .' (a dot).
 *          (Note that when \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, the user may wish to consider
 *          using H5Ovisit1() instead of H5Ovisit_by_name1().)
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.
 *
 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in a
 *          value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          The \p op callback function and the effect of the callback
 *          function’s return value on the application are described
 *          in H5Ovisit1().
 *
 *          The H5O_info1_t \c struct is defined in H5Opublic.h
 *          and described in the H5Oget_info1() function entry.
 *
 *          The H5Ovisit_by_name1() \p op_data parameter is a user-defined
 *          pointer to the data required to process objects in the course
 *          of the iteration. This pointer is passed back to each step of
 *          the iteration in the callback function’s \p op_data parameter.
 *
 *          \p lapl_id is a link access property list. In the general case,
 *          when default link access properties are acceptable, this can
 *          be passed in as #H5P_DEFAULT. An example of a situation that
 *          requires a non-default link access property list is when
 *          the link is an external link; an external link may require
 *          that a link prefix be set in a link access property list
 *          (see H5Pset_elink_prefix()).
 *
 *          H5Lvisit_by_name1() and H5Ovisit_by_name1() are companion
 *          functions: one for examining and operating on links; the other
 *          for examining and operating on the objects that those links point to.
 *          Both functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires.
 *
 * \version 1.10.5 The macro #H5Ovisit_by_name was removed and the function
 *          H5Ovisit_by_name1() was copied to #H5Ovisit_by_name.
 * \version 1.10.3 The H5Ovisit_by_name() function was renamed to H5Ovisit_by_name1(),
 *          and the macro #H5Ovisit_by_name was created.
 * \version 1.8.11 Fortran subroutine introduced in this release.
 *
 * \since 1.8.0
 *
 */
H5_DLL herr_t H5Ovisit_by_name1(hid_t loc_id, const char *obj_name, H5_index_t idx_type,
                                H5_iter_order_t order, H5O_iterate1_t op, void *op_data, hid_t lapl_id);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects accessible from a specified object
 *
 * \fgdta_loc_obj_id{obj_id}
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 * \param[in] fields Flags specifying the fields to be retrieved to the
 *                   callback \p op
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Ovisit3() or the macro #H5Ovisit.
 *
 * \details H5Ovisit2() is a recursive iteration function to visit the
 *          object \p obj_id and, if \p obj_id is a group, all objects in
 *          and below it in an HDF5 file, thus providing a mechanism for
 *          an application to perform a common set of operations across all
 *          of those objects or a dynamically selected subset. For
 *          non-recursive iteration across the members of a group,
 *          see H5Literate1().
 *
 *          If \p obj_id is a group identifier, that group serves as the
 *          root of a recursive iteration. If \p obj_id is a file identifier,
 *          that file’s root group serves as the root of the recursive
 *          iteration.  If \p obj_id is an attribute identifier,
 *          then the object where the attribute is attached will be iterated.
 *          If \p obj_id is any other type of object, such as a dataset or
 *          named datatype, there is no iteration.
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.
 *
 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in
 *          a value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          The \p fields parameter contains flags to determine which fields will
 *          be retrieved by the \p op callback function. These flags are defined
 *          in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          H5Lvisit() and H5Ovisit() are companion functions: one for
 *          examining and operating on links; the other for examining
 *          and operating on the objects that those links point to. Both
 *          functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires. These functions assume
 *          that the membership of the group being iterated over remains
 *          unchanged through the iteration; if any of the links in the
 *          group change during the iteration, the resulting behavior
 *          is undefined.
 *
 *
 * \since 1.10.3
 *
 */
H5_DLL herr_t H5Ovisit2(hid_t obj_id, H5_index_t idx_type, H5_iter_order_t order, H5O_iterate1_t op,
                        void *op_data, unsigned fields);

/**
 *-------------------------------------------------------------------------
 * \ingroup H5O
 *
 * \brief Recursively visits all objects starting from a specified object
 *
 * \fgdta_loc_obj_id{loc_id}
 * \param[in] obj_name Name of the object, generally relative to
 *                     \p loc_id, that will serve as root of the iteration
 * \idx_type
 * \order
 * \param[in] op Callback function passing data regarding the object
 *               to the calling application
 * \param[in] op_data User-defined pointer to data required by the application
 *                    for its processing of the object
 * \param[in] fields Flags specifying the fields to be retrieved to the
 *                   callback function \p op
 * \lapl_id
 *
 * \return On success, returns the return value of the first operator
 *         that returns a positive value, or zero if all members were
 *         processed with no operator returning non-zero.
 *
 * \return On failure, returns a negative value if something goes wrong
 *         within the library, or the first negative value returned by
 *         an operator.
 *
 * \deprecated As of HDF5-1.12 this function has been deprecated in favor of
 *             the function H5Ovisit_by_name3() or the macro #H5Ovisit_by_name.
 *
 * \details H5Ovisit_by_name2() is a recursive iteration function to visit
 *          the object specified by the \p loc_id / \p obj_name parameter
 *          pair and, if that object is a group, all objects in and below it
 *          in an HDF5 file, thus providing a mechanism for an application to
 *          perform a common set of operations across all of those objects or
 *          a dynamically selected subset. For non-recursive iteration across
 *          the members of a group, see #H5Literate.
 *
 *          The object serving as the root of the iteration is specified
 *          by the \p loc_id / \p obj_name parameter pair. \p loc_id specifies
 *          a file or an object in a file;  if \p loc_id is an attribute identifier,
 *          the object where the attribute is attached will be used.
 *          \p obj_name specifies either an object in the file (with an absolute
 *          name based in the file’s root group) or an object name relative
 *          to \p loc_id. If \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, \p obj_name should be '\c .' (a dot).
 *          (Note that when \p loc_id fully specifies the object that is to serve
 *          as the root of the iteration, the user may wish to consider
 *          using H5Ovisit2() instead of #H5Ovisit_by_name.)
 *
 *          Two parameters are used to establish the iteration: \p idx_type
 *          and \p order.
 *
 *          \p idx_type specifies the index to be used. If the links in
 *          a group have not been indexed by the index type, they will
 *          first be sorted by that index then the iteration will begin;
 *          if the links have been so indexed, the sorting step will be
 *          unnecessary, so the iteration may begin more quickly.
 *
 *          Note that the index type passed in \p idx_type is a
 *          <em>best effort</em> setting. If the application passes in a
 *          value indicating iteration in creation order and a group is
 *          encountered that was not tracked in creation order, that group
 *          will be iterated over in alphanumeric order by name, or
 *          <em>name order</em>.  (<em>Name order</em> is the native order
 *          used by the HDF5 library and is always available.)
 *
 *          \p order specifies the order in which objects are to be inspected
 *          along the index specified in \p idx_type.
 *
 *          The \p op callback function and the effect of the callback
 *          function’s return value on the application are described
 *          in H5Ovisit2().
 *
 *          The H5O_info1_t \c struct is defined in H5Opublic.h
 *          and described in the H5Oget_info1() function entry.
 *
 *          The H5Ovisit_by_name2() \p op_data parameter is a user-defined
 *          pointer to the data required to process objects in the course
 *          of the iteration. This pointer is passed back to each step of
 *          the iteration in the callback function’s \p op_data parameter.
 *
 *          \p lapl_id is a link access property list. In the general case,
 *          when default link access properties are acceptable, this can
 *          be passed in as #H5P_DEFAULT. An example of a situation that
 *          requires a non-default link access property list is when
 *          the link is an external link; an external link may require
 *          that a link prefix be set in a link access property list
 *          (see H5Pset_elink_prefix()).
 *
 *          The \p fields parameter contains flags to determine which fields will
 *          be retrieved by the \p op callback function. These flags are defined
 *          in the H5Opublic.h file:
 *          \obj_info_fields
 *
 *          #H5Lvisit_by_name and #H5Ovisit_by_name are companion
 *          functions: one for examining and operating on links; the other
 *          for examining and operating on the objects that those links point to.
 *          Both functions ensure that by the time the function completes
 *          successfully, every link or object below the specified point
 *          in the file has been presented to the application for whatever
 *          processing the application requires.
 *
 * \since 1.10.3
 *
 */
H5_DLL herr_t H5Ovisit_by_name2(hid_t loc_id, const char *obj_name, H5_index_t idx_type,
                                H5_iter_order_t order, H5O_iterate1_t op, void *op_data, unsigned fields,
                                hid_t lapl_id);

#endif /* H5_NO_DEPRECATED_SYMBOLS */

#ifdef __cplusplus
}
#endif
#endif /* H5Opublic_H */