text: /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
   * 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.                                                        *
   * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
  
  /*
   * Purpose:     The Virtual Object Layer as described in documentation.
   *              The pupose is to provide an abstraction on how to access the
   *              underlying HDF5 container, whether in a local file with
   *              a specific file format, or remotely on other machines, etc...
   */
  
  /****************/
  /* Module Setup */
  /****************/
  
  #include "H5VLmodule.h" /* This source code file is part of the H5VL module */
  
  /***********/
  /* Headers */
  /***********/
  
  #include "H5private.h"   /* Generic Functions                                */
  #include "H5Eprivate.h"  /* Error handling                                   */
  #include "H5Fprivate.h"  /* File access	                                     */
  #include "H5Iprivate.h"  /* IDs                                              */
  #include "H5MMprivate.h" /* Memory management                                */
  #include "H5Pprivate.h"  /* Property lists                                   */
  #include "H5PLprivate.h" /* Plugins                                          */
  #include "H5VLpkg.h"     /* Virtual Object Layer                             */
  
  /****************/
  /* Local Macros */
  /****************/
  
  /******************/
  /* Local Typedefs */
  /******************/
  
  /* Structure used when trying to find a
   * VOL connector to open a given file with.
   */
  typedef struct H5VL_file_open_find_connector_t {
      const char *           filename;
      const H5VL_class_t *   cls;
      H5VL_connector_prop_t *connector_prop;
      hid_t                  fapl_id;
  } H5VL_file_open_find_connector_t;
  
  /********************/
  /* Package Typedefs */
  /********************/
  
  /********************/
  /* Local Prototypes */
  /********************/
  static void * H5VL__attr_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                  const char *name, hid_t type_id, hid_t space_id, hid_t acpl_id, hid_t aapl_id,
                                  hid_t dxpl_id, void **req);
  static void * H5VL__attr_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                const char *name, hid_t aapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__attr_read(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, void *buf, hid_t dxpl_id,
                                void **req);
  static herr_t H5VL__attr_write(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, const void *buf,
                                 hid_t dxpl_id, void **req);
  static herr_t H5VL__attr_get(void *obj, const H5VL_class_t *cls, H5VL_attr_get_t get_type, hid_t dxpl_id,
                               void **req, va_list arguments);
  static herr_t H5VL__attr_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                    H5VL_attr_specific_t specific_type, hid_t dxpl_id, void **req,
                                    va_list arguments);
  static herr_t H5VL__attr_optional(void *obj, const H5VL_class_t *cls, H5VL_attr_optional_t opt_type,
                                    hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__attr_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
  static void * H5VL__dataset_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                     const char *name, hid_t lcpl_id, hid_t type_id, hid_t space_id,
                                     hid_t dcpl_id, hid_t dapl_id, hid_t dxpl_id, void **req);
  static void * H5VL__dataset_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                   const char *name, hid_t dapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__dataset_read(void *dset, const H5VL_class_t *cls, hid_t mem_type_id, hid_t mem_space_id,
                                   hid_t file_space_id, hid_t dxpl_id, void *buf, void **req);
  static herr_t H5VL__dataset_write(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, hid_t mem_space_id,
                                    hid_t file_space_id, hid_t dxpl_id, const void *buf, void **req);
  static herr_t H5VL__dataset_get(void *obj, const H5VL_class_t *cls, H5VL_dataset_get_t get_type,
                                  hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__dataset_specific(void *obj, const H5VL_class_t *cls,
                                       H5VL_dataset_specific_t specific_type, hid_t dxpl_id, void **req,
                                       va_list arguments);
  static herr_t H5VL__dataset_optional(void *obj, const H5VL_class_t *cls, H5VL_dataset_optional_t opt_type,
                                       hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__dataset_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
  static void * H5VL__datatype_commit(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                      const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id,
                                      hid_t tapl_id, hid_t dxpl_id, void **req);
  static void * H5VL__datatype_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                    const char *name, hid_t tapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__datatype_get(void *obj, const H5VL_class_t *cls, H5VL_datatype_get_t get_type,
                                   hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__datatype_specific(void *obj, const H5VL_class_t *cls,
                                        H5VL_datatype_specific_t specific_type, hid_t dxpl_id, void **req,
                                        va_list arguments);
  static herr_t H5VL__datatype_optional(void *obj, const H5VL_class_t *cls, H5VL_datatype_optional_t opt_type,
                                        hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__datatype_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
  static void * H5VL__file_create(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fcpl_id,
                                  hid_t fapl_id, hid_t dxpl_id, void **req);
  static void * H5VL__file_open(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fapl_id,
                                hid_t dxpl_id, void **req);
  static herr_t H5VL__file_open_find_connector_cb(H5PL_type_t plugin_type, const void *plugin_info,
                                                  void *op_data);
  static herr_t H5VL__file_get(void *obj, const H5VL_class_t *cls, H5VL_file_get_t get_type, hid_t dxpl_id,
                               void **req, va_list arguments);
  static herr_t H5VL__file_specific(void *obj, const H5VL_class_t *cls, H5VL_file_specific_t specific_type,
                                    hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__file_optional(void *obj, const H5VL_class_t *cls, H5VL_file_optional_t opt_type,
                                    hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__file_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
  static void * H5VL__group_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                   const char *name, hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id,
                                   void **req);
  static void * H5VL__group_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                 const char *name, hid_t gapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, hid_t dxpl_id,
                                void **req, va_list arguments);
  static herr_t H5VL__group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type,
                                     hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__group_optional(void *obj, const H5VL_class_t *cls, H5VL_group_optional_t opt_type,
                                     hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__group_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req);
  static herr_t H5VL__link_create(H5VL_link_create_type_t create_type, void *obj,
                                  const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, hid_t lcpl_id,
                                  hid_t lapl_id, hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__link_copy(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                                const H5VL_loc_params_t *loc_params2, const H5VL_class_t *cls, hid_t lcpl_id,
                                hid_t lapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__link_move(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                                const H5VL_loc_params_t *loc_params2, const H5VL_class_t *cls, hid_t lcpl_id,
                                hid_t lapl_id, hid_t dxpl_id, void **req);
  static herr_t H5VL__link_get(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                               H5VL_link_get_t get_type, hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__link_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                    H5VL_link_specific_t specific_type, hid_t dxpl_id, void **req,
                                    va_list arguments);
  static herr_t H5VL__link_optional(void *obj, const H5VL_class_t *cls, H5VL_link_optional_t opt_type,
                                    hid_t dxpl_id, void **req, va_list arguments);
  static void * H5VL__object_open(void *obj, const H5VL_loc_params_t *params, const H5VL_class_t *cls,
                                  H5I_type_t *opened_type, hid_t dxpl_id, void **req);
  static herr_t H5VL__object_copy(void *src_obj, const H5VL_loc_params_t *src_loc_params, const char *src_name,
                                  void *dst_obj, const H5VL_loc_params_t *dst_loc_params, const char *dst_name,
                                  const H5VL_class_t *cls, hid_t ocpypl_id, hid_t lcpl_id, hid_t dxpl_id,
                                  void **req);
  static herr_t H5VL__object_get(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                 H5VL_object_get_t get_type, hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__object_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                                      H5VL_object_specific_t specific_type, hid_t dxpl_id, void **req,
                                      va_list arguments);
  static herr_t H5VL__object_optional(void *obj, const H5VL_class_t *cls, H5VL_object_optional_t opt_type,
                                      hid_t dxpl_id, void **req, va_list arguments);
  static herr_t H5VL__introspect_get_conn_cls(void *obj, const H5VL_class_t *cls, H5VL_get_conn_lvl_t lvl,
                                              const H5VL_class_t **conn_cls);
  static herr_t H5VL__introspect_opt_query(void *obj, const H5VL_class_t *cls, H5VL_subclass_t subcls,
                                           int opt_type, hbool_t *supported);
  static herr_t H5VL__request_wait(void *req, const H5VL_class_t *cls, uint64_t timeout, H5ES_status_t *status);
  static herr_t H5VL__request_notify(void *req, const H5VL_class_t *cls, H5VL_request_notify_t cb, void *ctx);
  static herr_t H5VL__request_cancel(void *req, const H5VL_class_t *cls);
  static herr_t H5VL__request_specific(void *req, const H5VL_class_t *cls,
                                       H5VL_request_specific_t specific_type, va_list arguments);
  static herr_t H5VL__request_optional(void *req, const H5VL_class_t *cls, H5VL_request_optional_t opt_type,
                                       va_list arguments);
  static herr_t H5VL__request_free(void *req, const H5VL_class_t *cls);
  static herr_t H5VL__blob_put(void *obj, const H5VL_class_t *cls, const void *buf, size_t size, void *blob_id,
                               void *ctx);
  static herr_t H5VL__blob_get(void *obj, const H5VL_class_t *cls, const void *blob_id, void *buf, size_t size,
                               void *ctx);
  static herr_t H5VL__blob_specific(void *obj, const H5VL_class_t *cls, void *blob_id,
                                    H5VL_blob_specific_t specific_type, va_list arguments);
  static herr_t H5VL__blob_optional(void *obj, const H5VL_class_t *cls, void *blob_id,
                                    H5VL_blob_optional_t opt_type, va_list arguments);
  static herr_t H5VL__token_cmp(void *obj, const H5VL_class_t *cls, const H5O_token_t *token1,
                                const H5O_token_t *token2, int *cmp_value);
  static herr_t H5VL__token_to_str(void *obj, H5I_type_t obj_type, const H5VL_class_t *cls,
                                   const H5O_token_t *token, char **token_str);
  static herr_t H5VL__token_from_str(void *obj, H5I_type_t obj_type, const H5VL_class_t *cls,
                                     const char *token_str, H5O_token_t *token);
  static herr_t H5VL__optional(void *obj, const H5VL_class_t *cls, int op_type, hid_t dxpl_id, void **req,
                               va_list arguments);
  
  /*********************/
  /* Package Variables */
  /*********************/
  
  /*****************************/
  /* Library Private Variables */
  /*****************************/
  
  /*******************/
  /* Local Variables */
  /*******************/
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLinitialize
   *
   * Purpose:     Calls the connector-specific callback to initialize the connector.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLinitialize(hid_t connector_id, hid_t vipl_id)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "ii", connector_id, vipl_id);
  
      /* Check args */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Invoke class' callback, if there is one */
      if (cls->initialize && cls->initialize(vipl_id) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "VOL connector did not initialize")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLinitialize() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLterminate
   *
   * Purpose:     Calls the connector-specific callback to terminate the connector.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLterminate(hid_t connector_id)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE1("e", "i", connector_id);
  
      /* Check args */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Invoke class' callback, if there is one */
      if (cls->terminate && cls->terminate() < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "VOL connector did not terminate cleanly")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLterminate() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLget_cap_flags
   *
   * Purpose:     Retrieves the capability flag for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLget_cap_flags(hid_t connector_id, unsigned *cap_flags)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "i*Iu", connector_id, cap_flags);
  
      /* Check args */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Retrieve capability flags */
      if (cap_flags)
          *cap_flags = cls->cap_flags;
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLget_cap_flags */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLget_value
   *
   * Purpose:     Retrieves the 'value' for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLget_value(hid_t connector_id, H5VL_class_value_t *value)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "i*VC", connector_id, value);
  
      /* Check args */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Retrieve connector value */
      if (value)
          *value = cls->value;
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLget_value */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_copy_connector_info
   *
   * Purpose:     Copy the VOL info for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_copy_connector_info(const H5VL_class_t *connector, void **dst_info, const void *src_info)
  {
      void * new_connector_info = NULL;    /* Copy of connector info */
      herr_t ret_value          = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(connector);
  
      /* Check for actual source info */
      if (src_info) {
          /* Allow the connector to copy or do it ourselves */
          if (connector->info_cls.copy) {
              if (NULL == (new_connector_info = (connector->info_cls.copy)(src_info)))
                  HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "connector info copy callback failed")
          } /* end if */
          else if (connector->info_cls.size > 0) {
              if (NULL == (new_connector_info = H5MM_malloc(connector->info_cls.size)))
                  HGOTO_ERROR(H5E_VOL, H5E_CANTALLOC, FAIL, "connector info allocation failed")
              H5MM_memcpy(new_connector_info, src_info, connector->info_cls.size);
          } /* end else-if */
          else
              HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "no way to copy connector info")
      } /* end if */
  
      /* Set the connector info for the copy */
      *dst_info = new_connector_info;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_copy_connector_info() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLcopy_connector_info
   *
   * Purpose:     Copies a VOL connector's info object
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLcopy_connector_info(hid_t connector_id, void **dst_vol_info, void *src_vol_info)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE3("e", "i**x*x", connector_id, dst_vol_info, src_vol_info);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Copy the VOL connector's info object */
      if (H5VL_copy_connector_info(cls, dst_vol_info, src_vol_info) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "unable to copy VOL connector info object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLcopy_connector_info() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_cmp_connector_info
   *
   * Purpose:     Compare VOL info for a connector.  Sets *cmp_value to
   *              positive if INFO1 is greater than INFO2, negative if
   *              INFO2 is greater than INFO1 and zero if INFO1 and
   *              INFO2 are equal.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_cmp_connector_info(const H5VL_class_t *connector, int *cmp_value, const void *info1, const void *info2)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(connector);
      HDassert(cmp_value);
  
      /* Take care of cases where one or both pointers is NULL */
      if (info1 == NULL && info2 != NULL) {
          *cmp_value = -1;
          HGOTO_DONE(SUCCEED);
      } /* end if */
      if (info1 != NULL && info2 == NULL) {
          *cmp_value = 1;
          HGOTO_DONE(SUCCEED);
      } /* end if */
      if (info1 == NULL && info2 == NULL) {
          *cmp_value = 0;
          HGOTO_DONE(SUCCEED);
      } /* end if */
  
      /* Use the class's info comparison routine to compare the info objects,
       * if there is a a callback, otherwise just compare the info objects as
       * memory buffers
       */
      if (connector->info_cls.cmp) {
          if ((connector->info_cls.cmp)(cmp_value, info1, info2) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTCOMPARE, FAIL, "can't compare connector info")
      } /* end if */
      else {
          HDassert(connector->info_cls.size > 0);
          *cmp_value = HDmemcmp(info1, info2, connector->info_cls.size);
      } /* end else */
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_cmp_connector_info() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLcmp_connector_info
   *
   * Purpose:     Compares two connector info objects
   *
   * Note:	Both info objects must be from the same VOL connector class
   *
   * Return:      Success:    Non-negative, with *cmp set to positive if
   *			    info1 is greater than info2, negative if info2
   *			    is greater than info1 and zero if info1 and info2
   *			    are equal.
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLcmp_connector_info(int *cmp, hid_t connector_id, const void *info1, const void *info2)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API(FAIL)
      H5TRACE4("e", "*Isi*x*x", cmp, connector_id, info1, info2);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Compare the two VOL connector info objects */
      if (cmp)
          H5VL_cmp_connector_info(cls, cmp, info1, info2);
  
  done:
      FUNC_LEAVE_API(ret_value)
  } /* H5VLcmp_connector_info() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_free_connector_info
   *
   * Purpose:     Free VOL info for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_free_connector_info(hid_t connector_id, const void *info)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(connector_id > 0);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_VOL, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Only free info object, if it's non-NULL */
      if (info) {
          /* Allow the connector to free info or do it ourselves */
          if (cls->info_cls.free) {
              /* Cast through uintptr_t to de-const memory */
              if ((cls->info_cls.free)((void *)(uintptr_t)info) < 0)
                  HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "connector info free request failed")
          }
          else
              H5MM_xfree_const(info);
      }
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_free_connector_info() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLfree_connector_info
   *
   * Purpose:     Free VOL connector info object
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLfree_connector_info(hid_t connector_id, void *info)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "i*x", connector_id, info);
  
      /* Free the VOL connector info object */
      if (H5VL_free_connector_info(connector_id, info) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "unable to release VOL connector info object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLfree_connector_info() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLconnector_info_to_str
   *
   * Purpose:     Serialize a connector's info into a string
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLconnector_info_to_str(const void *info, hid_t connector_id, char **str)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE3("e", "*xi**s", info, connector_id, str);
  
      /* Only serialize info object, if it's non-NULL */
      if (info) {
          H5VL_class_t *cls; /* VOL connector's class struct */
  
          /* Check args and get class pointer */
          if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
              HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
          /* Allow the connector to serialize info */
          if (cls->info_cls.to_str) {
              if ((cls->info_cls.to_str)(info, str) < 0)
                  HGOTO_ERROR(H5E_VOL, H5E_CANTSERIALIZE, FAIL, "can't serialize connector info")
          } /* end if */
          else
              *str = NULL;
      } /* end if */
      else
          *str = NULL;
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLconnector_info_to_str() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLconnector_str_to_info
   *
   * Purpose:     Deserialize a string into a connector's info
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLconnector_str_to_info(const char *str, hid_t connector_id, void **info)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE3("e", "*si**x", str, connector_id, info);
  
      /* Call internal routine */
      if (H5VL__connector_str_to_info(str, connector_id, info) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTDECODE, FAIL, "can't deserialize connector info")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLconnector_str_to_info() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLget_object
   *
   * Purpose:     Retrieves an underlying object.
   *
   * Return:      Success:    Non-NULL
   *              Failure:    NULL
   *
   *---------------------------------------------------------------------------
   */
  void *
  H5VLget_object(void *obj, hid_t connector_id)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("*x", "*xi", obj, connector_id);
  
      /* Check args */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Check for 'get_object' callback in connector */
      if (cls->wrap_cls.get_object)
          ret_value = (cls->wrap_cls.get_object)(obj);
      else
          ret_value = obj;
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLget_object */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_get_wrap_ctx
   *
   * Purpose:     Retrieve the VOL object wrapping context for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_get_wrap_ctx(const H5VL_class_t *connector, void *obj, void **wrap_ctx)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(connector);
      HDassert(obj);
      HDassert(wrap_ctx);
  
      /* Allow the connector to copy or do it ourselves */
      if (connector->wrap_cls.get_wrap_ctx) {
          /* Sanity check */
          HDassert(connector->wrap_cls.free_wrap_ctx);
  
          /* Invoke connector's callback */
          if ((connector->wrap_cls.get_wrap_ctx)(obj, wrap_ctx) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "connector wrap context callback failed")
      } /* end if */
      else
          *wrap_ctx = NULL;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_get_wrap_ctx() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLget_wrap_ctx
   *
   * Purpose:     Get a VOL connector's object wrapping context
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLget_wrap_ctx(void *obj, hid_t connector_id, void **wrap_ctx)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE3("e", "*xi**x", obj, connector_id, wrap_ctx);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Get the VOL connector's object wrapper */
      if (H5VL_get_wrap_ctx(cls, obj, wrap_ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to retrieve VOL connector object wrap context")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLget_wrap_ctx() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_wrap_object
   *
   * Purpose:     Wrap an object with connector
   *
   * Return:      Success:    Non-NULL
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_wrap_object(const H5VL_class_t *connector, void *wrap_ctx, void *obj, H5I_type_t obj_type)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Sanity checks */
      HDassert(connector);
      HDassert(obj);
  
      /* Only wrap object if there's a wrap context */
      if (wrap_ctx) {
          /* Ask the connector to wrap the object */
          if (NULL == (ret_value = (connector->wrap_cls.wrap_object)(obj, obj_type, wrap_ctx)))
              HGOTO_ERROR(H5E_VOL, H5E_CANTGET, NULL, "can't wrap object")
      } /* end if */
      else
          ret_value = obj;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_wrap_object() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLwrap_object
   *
   * Purpose:     Asks a connector to wrap an underlying object.
   *
   * Return:      Success:    Non-NULL
   *              Failure:    NULL
   *
   *---------------------------------------------------------------------------
   */
  void *
  H5VLwrap_object(void *obj, H5I_type_t obj_type, hid_t connector_id, void *wrap_ctx)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("*x", "*xIti*x", obj, obj_type, connector_id, wrap_ctx);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Wrap the object */
      if (NULL == (ret_value = H5VL_wrap_object(cls, wrap_ctx, obj, obj_type)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, NULL, "unable to wrap object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLwrap_object */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_unwrap_object
   *
   * Purpose:     Unwrap an object from connector
   *
   * Return:      Success:    Non-NULL
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_unwrap_object(const H5VL_class_t *connector, void *obj)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Sanity checks */
      HDassert(connector);
      HDassert(obj);
  
      /* Only unwrap object if there's an unwrap callback */
      if (connector->wrap_cls.wrap_object) {
          /* Ask the connector to unwrap the object */
          if (NULL == (ret_value = (connector->wrap_cls.unwrap_object)(obj)))
              HGOTO_ERROR(H5E_VOL, H5E_CANTGET, NULL, "can't unwrap object")
      } /* end if */
      else
          ret_value = obj;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_unwrap_object() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLunwrap_object
   *
   * Purpose:     Unwrap an object from connector
   *
   * Return:      Success:    Non-NULL
   *              Failure:    NULL
   *
   *---------------------------------------------------------------------------
   */
  void *
  H5VLunwrap_object(void *obj, hid_t connector_id)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("*x", "*xi", obj, connector_id);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Unwrap the object */
      if (NULL == (ret_value = H5VL_unwrap_object(cls, obj)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, NULL, "unable to unwrap object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLunwrap_object */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_free_wrap_ctx
   *
   * Purpose:     Free object wrapping context for a connector
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_free_wrap_ctx(const H5VL_class_t *connector, void *wrap_ctx)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(connector);
  
      /* Only free wrap context, if it's non-NULL */
      if (wrap_ctx) {
          /* Free the connector's object wrapping context */
          if ((connector->wrap_cls.free_wrap_ctx)(wrap_ctx) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "connector wrap context free request failed")
      } /* end if */
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_free_wrap_ctx() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLfree_wrap_ctx
   *
   * Purpose:     Release a VOL connector's object wrapping context
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLfree_wrap_ctx(void *wrap_ctx, hid_t connector_id)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "*xi", wrap_ctx, connector_id);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Release the VOL connector's object wrapper */
      if (H5VL_free_wrap_ctx(cls, wrap_ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "unable to release VOL connector object wrap context")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* H5VLfree_wrap_ctx() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__attr_create
   *
   * Purpose:     Creates an attribute through the VOL
   *
   * Return:      Success: Pointer to the new attribute
   *              Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__attr_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                    hid_t type_id, hid_t space_id, hid_t acpl_id, hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.create)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'attr create' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->attr_cls.create)(obj, loc_params, name, type_id, space_id, acpl_id,
                                                      aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "attribute create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_attr_create
   *
   * Purpose:     Creates an attribute through the VOL
   *
   * Return:      Success: Pointer to the new attribute
   *              Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_attr_create(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                   hid_t type_id, hid_t space_id, hid_t acpl_id, hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__attr_create(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                 type_id, space_id, acpl_id, aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "attribute create failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_create
   *
   * Purpose:     Creates an attribute
   *
   * Return:      Success:    Pointer to the new attribute
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLattr_create(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                  hid_t type_id, hid_t space_id, hid_t acpl_id, hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE10("*x", "*x*xi*siiiii**x", obj, loc_params, connector_id, name, type_id, space_id, acpl_id,
                aapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__attr_create(obj, loc_params, cls, name, type_id, space_id, acpl_id,
                                                 aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to create attribute")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_open
   *
   * Purpose:	Opens an attribute through the VOL
   *
   * Return:      Success: Pointer to the attribute
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__attr_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                  hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'attr open' method")
  
      /* Call the corresponding VOL open callback */
      if (NULL == (ret_value = (cls->attr_cls.open)(obj, loc_params, name, aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "attribute open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_open
   *
   * Purpose:	Opens an attribute through the VOL
   *
   * Return:      Success: Pointer to the attribute
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_attr_open(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                 hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__attr_open(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                               aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "attribute open failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VLattr_open
   *
   * Purpose:     Opens an attribute
   *
   * Return:      Success:    Pointer to the attribute
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLattr_open(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                hid_t aapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("*x", "*x*xi*sii**x", obj, loc_params, connector_id, name, aapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__attr_open(obj, loc_params, cls, name, aapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "unable to open attribute")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_read
   *
   * Purpose:	Reads data from attr through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_read(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, void *buf, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.read)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr read' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->attr_cls.read)(obj, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_READERROR, FAIL, "attribute read failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_read() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_read
   *
   * Purpose:	Reads data from attr through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_read(const H5VL_object_t *vol_obj, hid_t mem_type_id, void *buf, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_read(vol_obj->data, vol_obj->connector->cls, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_READERROR, FAIL, "attribute read failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_read() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_read
   *
   * Purpose:     Reads data from an attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_read(void *obj, hid_t connector_id, hid_t mem_type_id, void *buf, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xii*xi**x", obj, connector_id, mem_type_id, buf, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_read(obj, cls, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_READERROR, FAIL, "unable to read attribute")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_read() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_write
   *
   * Purpose:	Writes data to attr through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_write(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, const void *buf, hid_t dxpl_id,
                   void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.write)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr write' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->attr_cls.write)(obj, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_WRITEERROR, FAIL, "write failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_write() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_write
   *
   * Purpose:	Writes data to attr through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_write(const H5VL_object_t *vol_obj, hid_t mem_type_id, const void *buf, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_write(vol_obj->data, vol_obj->connector->cls, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_WRITEERROR, FAIL, "write failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_write() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_write
   *
   * Purpose:     Writes data to an attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_write(void *obj, hid_t connector_id, hid_t mem_type_id, const void *buf, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xii*xi**x", obj, connector_id, mem_type_id, buf, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_write(obj, cls, mem_type_id, buf, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_WRITEERROR, FAIL, "unable to write attribute")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_write() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_get
   *
   * Purpose:	Get specific information about the attribute through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_get(void *obj, const H5VL_class_t *cls, H5VL_attr_get_t get_type, hid_t dxpl_id, void **req,
                 va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->attr_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "attribute get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_get
   *
   * Purpose:	Get specific information about the attribute through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_get(const H5VL_object_t *vol_obj, H5VL_attr_get_t get_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__attr_get(vol_obj->data, vol_obj->connector->cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "attribute get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_get
   *
   * Purpose:     Gets information about the attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_get(void *obj, hid_t connector_id, H5VL_attr_get_t get_type, hid_t dxpl_id, void **req,
               va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVai**xx", obj, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to get attribute information")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_specific
   *
   * Purpose:	Specific operation on attributes through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                      H5VL_attr_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr specific' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->attr_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_specific
   *
   * Purpose:	Specific operation on attributes through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_specific(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params,
                     H5VL_attr_specific_t specific_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value = H5VL__attr_specific(vol_obj->data, loc_params, vol_obj->connector->cls, specific_type,
                                           dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_specific
   *
   * Purpose:     Performs a connector-specific operation on an attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_specific(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id,
                    H5VL_attr_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("e", "*x*xiVbi**xx", obj, loc_params, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__attr_specific(obj, loc_params, cls, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__attr_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_optional(void *obj, const H5VL_class_t *cls, H5VL_attr_optional_t opt_type, hid_t dxpl_id,
                      void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr optional' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->attr_cls.optional)(obj, opt_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_attr_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_optional(const H5VL_object_t *vol_obj, H5VL_attr_optional_t opt_type, hid_t dxpl_id, void **req,
                     ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value = H5VL__attr_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req,
                                           arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_optional
   *
   * Purpose:     Performs an optional connector-specific operation on an attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_optional(void *obj, hid_t connector_id, H5VL_attr_optional_t opt_type, hid_t dxpl_id, void **req,
                    va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVsi**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__attr_optional(obj, cls, opt_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute attribute optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__attr_close
   *
   * Purpose:     Closes an attribute through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__attr_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->attr_cls.close)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'attr close' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->attr_cls.close)(obj, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "attribute close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__attr_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_attr_close
   *
   * Purpose:     Closes an attribute through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_attr_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_close(vol_obj->data, vol_obj->connector->cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "attribute close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_attr_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLattr_close
   *
   * Purpose:     Closes an attribute
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLattr_close(void *obj, hid_t connector_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xii**x", obj, connector_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__attr_close(obj, cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "unable to close attribute")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLattr_close() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_create
   *
   * Purpose:	Creates a dataset through the VOL
   *
   * Return:      Success: Pointer to new dataset
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__dataset_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                       const char *name, hid_t lcpl_id, hid_t type_id, hid_t space_id, hid_t dcpl_id,
                       hid_t dapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.create)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'dataset create' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->dataset_cls.create)(obj, loc_params, name, lcpl_id, type_id, space_id,
                                                         dcpl_id, dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "dataset create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_create
   *
   * Purpose:	Creates a dataset through the VOL
   *
   * Return:      Success: Pointer to new dataset
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_dataset_create(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                      hid_t lcpl_id, hid_t type_id, hid_t space_id, hid_t dcpl_id, hid_t dapl_id, hid_t dxpl_id,
                      void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL ==
          (ret_value = H5VL__dataset_create(vol_obj->data, loc_params, vol_obj->connector->cls, name, lcpl_id,
                                            type_id, space_id, dcpl_id, dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "dataset create failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_create
   *
   * Purpose:     Creates a dataset
   *
   * Return:      Success:    Pointer to the new dataset
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLdataset_create(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                     hid_t lcpl_id, hid_t type_id, hid_t space_id, hid_t dcpl_id, hid_t dapl_id, hid_t dxpl_id,
                     void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE11("*x", "*x*xi*siiiiii**x", obj, loc_params, connector_id, name, lcpl_id, type_id, space_id,
                dcpl_id, dapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__dataset_create(obj, loc_params, cls, name, lcpl_id, type_id, space_id,
                                                    dcpl_id, dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to create dataset")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_open
   *
   * Purpose:	Opens a dataset through the VOL
   *
   * Return:      Success: Pointer to dataset
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__dataset_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                     hid_t dapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'dataset open' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->dataset_cls.open)(obj, loc_params, name, dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "dataset open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_open
   *
   * Purpose:	Opens a dataset through the VOL
   *
   * Return:      Success: Pointer to dataset
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_dataset_open(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                    hid_t dapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__dataset_open(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                  dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "dataset open failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_open
   *
   * Purpose:     Opens a dataset
   *
   * Return:      Success:    Pointer to the new dataset
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLdataset_open(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                   hid_t dapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("*x", "*x*xi*sii**x", obj, loc_params, connector_id, name, dapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__dataset_open(obj, loc_params, cls, name, dapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "unable to open dataset")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_read
   *
   * Purpose:	Reads data from dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_read(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, hid_t mem_space_id,
                     hid_t file_space_id, hid_t dxpl_id, void *buf, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.read)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset read' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.read)(obj, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_READERROR, FAIL, "dataset read failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_read() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_read
   *
   * Purpose:	Reads data from dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_read(const H5VL_object_t *vol_obj, hid_t mem_type_id, hid_t mem_space_id, hid_t file_space_id,
                    hid_t dxpl_id, void *buf, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_read(vol_obj->data, vol_obj->connector->cls, mem_type_id, mem_space_id, file_space_id,
                             dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_READERROR, FAIL, "dataset read failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_read() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_read
   *
   * Purpose:     Reads data from a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_read(void *obj, hid_t connector_id, hid_t mem_type_id, hid_t mem_space_id, hid_t file_space_id,
                   hid_t dxpl_id, void *buf, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE8("e", "*xiiiii*x**x", obj, connector_id, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf,
               req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_read(obj, cls, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTINIT, FAIL, "unable to read dataset")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_read() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_write
   *
   * Purpose:	Writes data from dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_write(void *obj, const H5VL_class_t *cls, hid_t mem_type_id, hid_t mem_space_id,
                      hid_t file_space_id, hid_t dxpl_id, const void *buf, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.write)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset write' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.write)(obj, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_WRITEERROR, FAIL, "dataset write failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_write() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_write
   *
   * Purpose:	Writes data from dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_write(const H5VL_object_t *vol_obj, hid_t mem_type_id, hid_t mem_space_id, hid_t file_space_id,
                     hid_t dxpl_id, const void *buf, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_write(vol_obj->data, vol_obj->connector->cls, mem_type_id, mem_space_id, file_space_id,
                              dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_WRITEERROR, FAIL, "dataset write failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_write() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_write
   *
   * Purpose:     Writes data to a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_write(void *obj, hid_t connector_id, hid_t mem_type_id, hid_t mem_space_id, hid_t file_space_id,
                    hid_t dxpl_id, const void *buf, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE8("e", "*xiiiii*x**x", obj, connector_id, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf,
               req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_write(obj, cls, mem_type_id, mem_space_id, file_space_id, dxpl_id, buf, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTINIT, FAIL, "unable to write dataset")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_write() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_get
   *
   * Purpose:	Get specific information about the dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_get(void *obj, const H5VL_class_t *cls, H5VL_dataset_get_t get_type, hid_t dxpl_id, void **req,
                    va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "dataset get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_get
   *
   * Purpose:	Get specific information about the dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_get(const H5VL_object_t *vol_obj, H5VL_dataset_get_t get_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__dataset_get(vol_obj->data, vol_obj->connector->cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "dataset get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_get
   *
   * Purpose:     Gets information about a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_get(void *obj, hid_t connector_id, H5VL_dataset_get_t get_type, hid_t dxpl_id, void **req,
                  va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVci**xx", obj, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute dataset get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_specific
   *
   * Purpose:	Specific operation on datasets through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_specific(void *obj, const H5VL_class_t *cls, H5VL_dataset_specific_t specific_type,
                         hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset specific' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_specific
   *
   * Purpose:	Specific operation on datasets through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_specific(const H5VL_object_t *vol_obj, H5VL_dataset_specific_t specific_type, hid_t dxpl_id,
                        void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__dataset_specific(vol_obj->data, vol_obj->connector->cls, specific_type, dxpl_id, req,
                                 arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_specific
   *
   * Purpose:     Performs a connector-specific operation on a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_specific(void *obj, hid_t connector_id, H5VL_dataset_specific_t specific_type, hid_t dxpl_id,
                       void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVdi**xx", obj, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__dataset_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_optional(void *obj, const H5VL_class_t *cls, H5VL_dataset_optional_t opt_type, hid_t dxpl_id,
                         void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.optional)(obj, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_dataset_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_optional(const H5VL_object_t *vol_obj, H5VL_dataset_optional_t opt_type, hid_t dxpl_id,
                        void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__dataset_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_optional
   *
   * Purpose:     Performs an optional connector-specific operation on a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_optional(void *obj, hid_t connector_id, H5VL_dataset_optional_t opt_type, hid_t dxpl_id,
                       void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVti**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_optional(obj, cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute dataset optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__dataset_close
   *
   * Purpose:     Closes a dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__dataset_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->dataset_cls.close)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'dataset close' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->dataset_cls.close)(obj, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "dataset close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__dataset_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_dataset_close
   *
   * Purpose:     Closes a dataset through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_dataset_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
      HDassert(vol_obj->data);
      HDassert(vol_obj->connector);
      HDassert(vol_obj->connector->cls);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_close(vol_obj->data, vol_obj->connector->cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "dataset close failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_dataset_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdataset_close
   *
   * Purpose:     Closes a dataset
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdataset_close(void *obj, hid_t connector_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xii**x", obj, connector_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__dataset_close(obj, cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "unable to close dataset")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdataset_close() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__datatype_commit
   *
   * Purpose:	Commits a datatype to the file through the VOL
   *
   * Return:      Success:    Pointer to the new datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__datatype_commit(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                        const char *name, hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id,
                        hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.commit)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'datatype commit' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->datatype_cls.commit)(obj, loc_params, name, type_id, lcpl_id, tcpl_id,
                                                          tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "datatype commit failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_commit() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_datatype_commit
   *
   * Purpose:	Commits a datatype to the file through the VOL
   *
   * Return:      Success:    Pointer to the new datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_datatype_commit(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                       hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__datatype_commit(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                     type_id, lcpl_id, tcpl_id, tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "datatype commit failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_commit() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_commit
   *
   * Purpose:     Commits a datatype to the file
   *
   * Return:      Success:    Pointer to the new datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLdatatype_commit(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                      hid_t type_id, hid_t lcpl_id, hid_t tcpl_id, hid_t tapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE10("*x", "*x*xi*siiiii**x", obj, loc_params, connector_id, name, type_id, lcpl_id, tcpl_id,
                tapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__datatype_commit(obj, loc_params, cls, name, type_id, lcpl_id, tcpl_id,
                                                     tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to commit datatype")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_commit() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__datatype_open
   *
   * Purpose:	Opens a named datatype through the VOL
   *
   * Return:      Success:    Pointer to the datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__datatype_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                      hid_t tapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_CANTINIT, NULL, "no datatype open callback")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->datatype_cls.open)(obj, loc_params, name, tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "datatype open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_datatype_open
   *
   * Purpose:	Opens a named datatype through the VOL
   *
   * Return:      Success:    Pointer to the datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_datatype_open(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                     hid_t tapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__datatype_open(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                   tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "datatype open failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_open
   *
   * Purpose:     Opens a named datatype
   *
   * Return:      Success:    Pointer to the datatype
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLdatatype_open(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                    hid_t tapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("*x", "*x*xi*sii**x", obj, loc_params, connector_id, name, tapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__datatype_open(obj, loc_params, cls, name, tapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "unable to open datatype")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__datatype_get
   *
   * Purpose:     Get specific information about the datatype through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__datatype_get(void *obj, const H5VL_class_t *cls, H5VL_datatype_get_t get_type, hid_t dxpl_id,
                     void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'datatype get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->datatype_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "datatype get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_datatype_get
   *
   * Purpose:     Get specific information about the datatype through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_datatype_get(const H5VL_object_t *vol_obj, H5VL_datatype_get_t get_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__datatype_get(vol_obj->data, vol_obj->connector->cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "datatype get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_get
   *
   * Purpose:     Gets information about the datatype
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdatatype_get(void *obj, hid_t connector_id, H5VL_datatype_get_t get_type, hid_t dxpl_id, void **req,
                   va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVei**xx", obj, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no `datatype get' method")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__datatype_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute datatype get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__datatype_specific
   *
   * Purpose:	Specific operation on datatypes through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__datatype_specific(void *obj, const H5VL_class_t *cls, H5VL_datatype_specific_t specific_type,
                          hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'datatype specific' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->datatype_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_datatype_specific
   *
   * Purpose:	Specific operation on datatypes through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_datatype_specific(const H5VL_object_t *vol_obj, H5VL_datatype_specific_t specific_type, hid_t dxpl_id,
                         void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__datatype_specific(vol_obj->data, vol_obj->connector->cls, specific_type, dxpl_id, req,
                                  arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_specific
   *
   * Purpose:     Performs a connector-specific operation on a datatype
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdatatype_specific(void *obj, hid_t connector_id, H5VL_datatype_specific_t specific_type, hid_t dxpl_id,
                        void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVfi**xx", obj, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__datatype_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__datatype_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__datatype_optional(void *obj, const H5VL_class_t *cls, H5VL_datatype_optional_t opt_type, hid_t dxpl_id,
                          void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'datatype optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->datatype_cls.optional)(obj, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_datatype_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_datatype_optional(const H5VL_object_t *vol_obj, H5VL_datatype_optional_t opt_type, hid_t dxpl_id,
                         void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__datatype_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req, arguments) <
          0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_optional
   *
   * Purpose:     Performs an optional connector-specific operation on a datatype
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdatatype_optional(void *obj, hid_t connector_id, H5VL_datatype_optional_t opt_type, hid_t dxpl_id,
                        void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVui**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__datatype_optional(obj, cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute datatype optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__datatype_close
   *
   * Purpose:     Closes a datatype through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__datatype_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->datatype_cls.close)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'datatype close' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->datatype_cls.close)(obj, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "datatype close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__datatype_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_datatype_close
   *
   * Purpose:     Closes a datatype through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_datatype_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__datatype_close(vol_obj->data, vol_obj->connector->cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "datatype close failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_datatype_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLdatatype_close
   *
   * Purpose:     Closes a datatype
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLdatatype_close(void *obj, hid_t connector_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xii**x", obj, connector_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__datatype_close(obj, cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "unable to close datatype")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLdatatype_close() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__file_create
   *
   * Purpose:	Creates a file through the VOL
   *
   * Note:	Does not have a 'static' version of the routine, since there's
   *		no objects in the container before this operation completes.
   *
   * Return:      Success: Pointer to new file
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__file_create(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id,
                    hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.create)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'file create' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->file_cls.create)(name, flags, fcpl_id, fapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "file create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_file_create
   *
   * Purpose:	Creates a file through the VOL
   *
   * Note:	Does not have a 'static' version of the routine, since there's
   *		no objects in the container before this operation completes.
   *
   * Return:      Success: Pointer to new file
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_file_create(const H5VL_connector_prop_t *connector_prop, const char *name, unsigned flags, hid_t fcpl_id,
                   hid_t fapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL Class structure for callback info    */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Get the connector's class */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_prop->connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__file_create(cls, name, flags, fcpl_id, fapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "file create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_create
   *
   * Purpose:     Creates a file
   *
   * Return:      Success:    Pointer to the new file
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLfile_create(const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id, hid_t dxpl_id, void **req)
  {
      H5P_genplist_t *      plist;            /* Property list pointer */
      H5VL_connector_prop_t connector_prop;   /* Property for VOL connector ID & info */
      H5VL_class_t *        cls;              /* VOL connector's class struct */
      void *                ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("*x", "*sIuiii**x", name, flags, fcpl_id, fapl_id, dxpl_id, req);
  
      /* Get the VOL info from the fapl */
      if (NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a file access property list")
      if (H5P_peek(plist, H5F_ACS_VOL_CONN_NAME, &connector_prop) < 0)
          HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get VOL connector info")
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_prop.connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__file_create(cls, name, flags, fcpl_id, fapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to create file")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__file_open
   *
   * Purpose:	Opens a file through the VOL.
   *
   * Return:      Success: Pointer to file.
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__file_open(const H5VL_class_t *cls, const char *name, unsigned flags, hid_t fapl_id, hid_t dxpl_id,
                  void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'file open' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->file_cls.open)(name, flags, fapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__file_open_find_connector_cb
   *
   * Purpose:     Iteration callback for H5PL_iterate that tries to find the
   *              correct VOL connector to open a file with when
   *              H5VL_file_open fails for its given VOL connector. Iterates
   *              through all of the available VOL connector plugins until
   *              H5Fis_accessible returns true for the given filename and
   *              VOL connector.
   *
   * Return:      H5_ITER_CONT if current plugin can't open the given file
   *              H5_ITER_STOP if current plugin can open given file
   *              H5_ITER_ERROR if an error occurs while trying to determine
   *                  if current plugin can open given file.
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__file_open_find_connector_cb(H5PL_type_t plugin_type, const void *plugin_info, void *op_data)
  {
      H5VL_file_open_find_connector_t *udata = (H5VL_file_open_find_connector_t *)op_data;
      const H5VL_class_t *             cls   = (const H5VL_class_t *)plugin_info;
      H5P_genplist_t *                 fapl_plist;
      H5P_genplist_t *                 fapl_plist_copy;
      herr_t                           status;
      htri_t                           is_accessible = FALSE;
      hid_t                            connector_id  = H5I_INVALID_HID;
      hid_t                            fapl_id       = H5I_INVALID_HID;
      herr_t                           ret_value     = H5_ITER_CONT;
  
      FUNC_ENTER_STATIC
  
      HDassert(udata);
      HDassert(udata->filename);
      HDassert(udata->connector_prop);
      HDassert(cls);
      HDassert(plugin_type == H5PL_TYPE_VOL);
  
      /* Silence compiler */
      (void)plugin_type;
  
      udata->cls = cls;
  
      /* Attempt to register plugin as a VOL connector */
      if ((connector_id = H5VL__register_connector_by_class(cls, TRUE, H5P_VOL_INITIALIZE_DEFAULT)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTREGISTER, H5_ITER_ERROR, "unable to register VOL connector")
  
      /* Setup FAPL with registered VOL connector */
      if (NULL == (fapl_plist = (H5P_genplist_t *)H5I_object_verify(udata->fapl_id, H5I_GENPROP_LST)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5_ITER_ERROR, "not a property list")
      if ((fapl_id = H5P_copy_plist(fapl_plist, TRUE)) < 0)
          HGOTO_ERROR(H5E_PLIST, H5E_CANTCOPY, H5_ITER_ERROR, "can't copy fapl");
      if (NULL == (fapl_plist_copy = (H5P_genplist_t *)H5I_object_verify(fapl_id, H5I_GENPROP_LST)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5_ITER_ERROR, "not a property list")
      if (H5P_set_vol(fapl_plist_copy, connector_id, NULL) < 0)
          HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, H5_ITER_ERROR, "can't set VOL connector on fapl")
  
      /* Check if file is accessible with given VOL connector */
      H5E_BEGIN_TRY
      {
          status = H5VL_file_specific(NULL, H5VL_FILE_IS_ACCESSIBLE, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL,
                                      fapl_id, udata->filename, &is_accessible);
      }
      H5E_END_TRY;
  
      /* If the file was accessible with the current VOL connector, return
       * the FAPL with that VOL connector set on it. Errors are ignored here
       * as some VOL connectors may not support H5Fis_accessible.
       */
      if (status == SUCCEED && is_accessible > 0) {
          /* Modify 'connector_prop' to point to the VOL connector that
           * was actually used to open the file, rather than the original
           * VOL connector that was requested.
           */
          udata->connector_prop->connector_id   = connector_id;
          udata->connector_prop->connector_info = NULL;
  
          udata->fapl_id = fapl_id;
          ret_value      = H5_ITER_STOP;
      } /* end if */
  
  done:
      if (ret_value != H5_ITER_STOP) {
          if (fapl_id >= 0 && H5I_dec_app_ref(fapl_id) < 0)
              HDONE_ERROR(H5E_PLIST, H5E_CANTCLOSEOBJ, H5_ITER_ERROR, "can't close fapl")
          if (connector_id >= 0 && H5I_dec_app_ref(connector_id) < 0)
              HDONE_ERROR(H5E_ATOM, H5E_CANTCLOSEOBJ, H5_ITER_ERROR, "can't close VOL connector ID")
      } /* end if */
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_open_find_connector_cb() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_file_open
   *
   * Purpose:	Opens a file through the VOL.
   *
   * Note:	Does not have a 'static' version of the routine, since there's
   *		no objects in the container before this operation completes.
   *
   * Return:      Success: Pointer to file.
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_file_open(H5VL_connector_prop_t *connector_prop, const char *name, unsigned flags, hid_t fapl_id,
                 hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL Class structure for callback info    */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Get the connector's class */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_prop->connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__file_open(cls, name, flags, fapl_id, dxpl_id, req))) {
          H5VL_file_open_find_connector_t find_connector_ud;
          hbool_t                         find_connector;
          hbool_t                         connector_available = FALSE;
  
          /* Opening the file failed - Determine whether we should search
           * the plugin path to see if any other VOL connectors are available
           * to attempt to open the file with. This only occurs if no particular
           * VOL connector was specified (either via a FAPL or the
           * HDF5_VOL_CONNECTOR environment variable).
           */
          find_connector = !getenv("HDF5_VOL_CONNECTOR") && ((H5P_FILE_ACCESS_DEFAULT == fapl_id) ||
                                                             connector_prop->connector_id == H5_DEFAULT_VOL);
  
          if (find_connector) {
              herr_t iter_ret;
  
              find_connector_ud.connector_prop = connector_prop;
              find_connector_ud.filename       = name;
              find_connector_ud.cls            = NULL;
              find_connector_ud.fapl_id        = fapl_id;
  
              iter_ret = H5PL_iterate(H5PL_ITER_TYPE_VOL, H5VL__file_open_find_connector_cb,
                                      (void *)&find_connector_ud);
              if (iter_ret < 0)
                  HGOTO_ERROR(H5E_VOL, H5E_BADITER, NULL,
                              "failed to iterate over available VOL connector plugins")
              else if (iter_ret)
                  connector_available = TRUE;
          } /* end if */
  
          /* If one of the available VOL connector plugins is
           * able to open the file, clear the error stack from any
           * previous file open failures and then open the file.
           * Otherwise, if no VOL connectors are available, throw
           * error from original file open failure.
           */
          if (connector_available) {
              H5E_clear_stack(NULL);
  
              if (NULL == (ret_value = H5VL__file_open(find_connector_ud.cls, name, flags,
                                                       find_connector_ud.fapl_id, dxpl_id, req)))
                  HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "can't open file '%s' with VOL connector '%s'",
                              name, find_connector_ud.cls->name)
          }
          else
              HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "open failed")
      } /* end if */
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_open
   *
   * Purpose:     Opens a file
   *
   * Return:      Success:    Pointer to the file
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLfile_open(const char *name, unsigned flags, hid_t fapl_id, hid_t dxpl_id, void **req)
  {
      H5P_genplist_t *      plist;            /* Property list pointer */
      H5VL_connector_prop_t connector_prop;   /* Property for VOL connector ID & info */
      H5VL_class_t *        cls;              /* VOL connector's class struct */
      void *                ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("*x", "*sIuii**x", name, flags, fapl_id, dxpl_id, req);
  
      /* Get the VOL info from the fapl */
      if (NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a file access property list")
      if (H5P_peek(plist, H5F_ACS_VOL_CONN_NAME, &connector_prop) < 0)
          HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get VOL connector info")
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_prop.connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__file_open(cls, name, flags, fapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "unable to open file")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__file_get
   *
   * Purpose:	Get specific information about the file through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__file_get(void *obj, const H5VL_class_t *cls, H5VL_file_get_t get_type, hid_t dxpl_id, void **req,
                 va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'file get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->file_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "file get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_file_get
   *
   * Purpose:	Get specific information about the file through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_file_get(const H5VL_object_t *vol_obj, H5VL_file_get_t get_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__file_get(vol_obj->data, vol_obj->connector->cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "file get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_get
   *
   * Purpose:     Gets information about the file
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLfile_get(void *obj, hid_t connector_id, H5VL_file_get_t get_type, hid_t dxpl_id, void **req,
               va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVgi**xx", obj, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute file get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__file_specific
   *
   * Purpose:	Perform File specific operations through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__file_specific(void *obj, const H5VL_class_t *cls, H5VL_file_specific_t specific_type, hid_t dxpl_id,
                      void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'file specific' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->file_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_file_specific
   *
   * Purpose:	Perform file specific operations through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_file_specific(const H5VL_object_t *vol_obj, H5VL_file_specific_t specific_type, hid_t dxpl_id,
                     void **req, ...)
  {
      const H5VL_class_t *cls;                       /* VOL connector's class struct */
      va_list             arguments;                 /* Argument list passed from the API call */
      hbool_t             arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t             vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t              ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Start access to the varargs, so they are available in all situations below */
      HDva_start(arguments, req);
      arg_started = TRUE;
  
      /* Special treatment of file access check & delete operations */
      /* (Retrieve the VOL connector from the FAPL, since the file isn't open) */
      if (specific_type == H5VL_FILE_IS_ACCESSIBLE || specific_type == H5VL_FILE_DELETE) {
          H5P_genplist_t *      plist;          /* Property list pointer */
          H5VL_connector_prop_t connector_prop; /* Property for VOL connector ID & info */
          va_list               tmp_args;       /* argument list passed from the API call */
          hid_t                 fapl_id;        /* File access property list for accessing the file */
  
          /* Get the file access property list to access the file */
          HDva_copy(tmp_args, arguments);
          fapl_id = HDva_arg(tmp_args, hid_t);
          HDva_end(tmp_args);
  
          /* Get the VOL info from the FAPL */
          if (NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
              HGOTO_ERROR(H5E_VOL, H5E_BADTYPE, FAIL, "not a file access property list")
          if (H5P_peek(plist, H5F_ACS_VOL_CONN_NAME, &connector_prop) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't get VOL connector info")
  
          /* Get class pointer */
          if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_prop.connector_id, H5I_VOL)))
              HGOTO_ERROR(H5E_VOL, H5E_BADTYPE, FAIL, "not a VOL connector ID")
      } /* end if */
      /* Set wrapper info in API context, for all other operations */
      else {
          /* Sanity check */
          HDassert(vol_obj);
  
          if (H5VL_set_vol_wrapper(vol_obj) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
          vol_wrapper_set = TRUE;
  
          /* Set the VOL connector class pointer */
          cls = vol_obj->connector->cls;
      } /* end else */
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_specific(vol_obj ? vol_obj->data : NULL, cls, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file specific failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_specific
   *
   * Purpose:     Performs a connector-specific operation on a file
   *
   * Note:	The 'obj' parameter is allowed to be NULL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLfile_specific(void *obj, hid_t connector_id, H5VL_file_specific_t specific_type, hid_t dxpl_id,
                    void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVhi**xx", obj, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute file specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__file_optional
   *
   * Purpose:	Perform a connector specific operation
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__file_optional(void *obj, const H5VL_class_t *cls, H5VL_file_optional_t opt_type, hid_t dxpl_id,
                      void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'file optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->file_cls.optional)(obj, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file optional failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_file_optional
   *
   * Purpose:	Perform a connector specific operation
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_file_optional(const H5VL_object_t *vol_obj, H5VL_file_optional_t opt_type, hid_t dxpl_id, void **req,
                     ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__file_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "file optional failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_optional
   *
   * Purpose:     Performs an optional connector-specific operation on a file
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLfile_optional(void *obj, hid_t connector_id, H5VL_file_optional_t opt_type, hid_t dxpl_id, void **req,
                    va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVvi**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_optional(obj, cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute file optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__file_close
   *
   * Purpose:     Closes a file through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__file_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->file_cls.close)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'file close' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->file_cls.close)(obj, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "file close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__file_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_file_close
   *
   * Purpose:     Closes a file through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_file_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_close(vol_obj->data, vol_obj->connector->cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "file close failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_file_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLfile_close
   *
   * Purpose:     Closes a file
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLfile_close(void *obj, hid_t connector_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xii**x", obj, connector_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__file_close(obj, cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEFILE, FAIL, "unable to close file")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLfile_close() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__group_create
   *
   * Purpose:	Creates a group through the VOL
   *
   * Return:      Success: Pointer to new group
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__group_create(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                     hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.create)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'group create' method")
  
      /* Call the corresponding VOL callback */
      if (NULL ==
          (ret_value = (cls->group_cls.create)(obj, loc_params, name, lcpl_id, gcpl_id, gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "group create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_group_create
   *
   * Purpose:	Creates a group through the VOL
   *
   * Return:      Success: Pointer to new group
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_group_create(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                    hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__group_create(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                  lcpl_id, gcpl_id, gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "group create failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_create
   *
   * Purpose:     Creates a group
   *
   * Return:      Success:    Pointer to the new group
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLgroup_create(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                   hid_t lcpl_id, hid_t gcpl_id, hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE9("*x", "*x*xi*siiii**x", obj, loc_params, connector_id, name, lcpl_id, gcpl_id, gapl_id, dxpl_id,
               req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL ==
          (ret_value = H5VL__group_create(obj, loc_params, cls, name, lcpl_id, gcpl_id, gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, NULL, "unable to create group")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__group_open
   *
   * Purpose:	Opens a group through the VOL
   *
   * Return:      Success: Pointer to group
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__group_open(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls, const char *name,
                   hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'group open' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->group_cls.open)(obj, loc_params, name, gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "group open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_group_open
   *
   * Purpose:	Opens a group through the VOL
   *
   * Return:      Success: Pointer to group
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_group_open(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, const char *name,
                  hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__group_open(vol_obj->data, loc_params, vol_obj->connector->cls, name,
                                                gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "group open failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_open
   *
   * Purpose:     Opens a group
   *
   * Return:      Success:    Pointer to the group
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLgroup_open(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, const char *name,
                 hid_t gapl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("*x", "*x*xi*sii**x", obj, loc_params, connector_id, name, gapl_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__group_open(obj, loc_params, cls, name, gapl_id, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTINIT, NULL, "unable to open group")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__group_get
   *
   * Purpose:	Get specific information about the group through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__group_get(void *obj, const H5VL_class_t *cls, H5VL_group_get_t get_type, hid_t dxpl_id, void **req,
                  va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'group get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->group_cls.get)(obj, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "group get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_group_get
   *
   * Purpose:	Get specific information about the group through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_group_get(const H5VL_object_t *vol_obj, H5VL_group_get_t get_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__group_get(vol_obj->data, vol_obj->connector->cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "group get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_get
   *
   * Purpose:     Gets information about the group
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLgroup_get(void *obj, hid_t connector_id, H5VL_group_get_t get_type, hid_t dxpl_id, void **req,
                va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVii**xx", obj, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__group_get(obj, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute group get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__group_specific
   *
   * Purpose:	Specific operation on groups through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__group_specific(void *obj, const H5VL_class_t *cls, H5VL_group_specific_t specific_type, hid_t dxpl_id,
                       void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'group specific' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->group_cls.specific)(obj, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_group_specific
   *
   * Purpose:	Specific operation on groups through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_group_specific(const H5VL_object_t *vol_obj, H5VL_group_specific_t specific_type, hid_t dxpl_id,
                      void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__group_specific(vol_obj->data, vol_obj->connector->cls, specific_type, dxpl_id, req, arguments) <
          0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_specific
   *
   * Purpose:     Performs a connector-specific operation on a group
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLgroup_specific(void *obj, hid_t connector_id, H5VL_group_specific_t specific_type, hid_t dxpl_id,
                     void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVji**xx", obj, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__group_specific(obj, cls, specific_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__group_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__group_optional(void *obj, const H5VL_class_t *cls, H5VL_group_optional_t opt_type, hid_t dxpl_id,
                       void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'group optional' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->group_cls.optional)(obj, opt_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_group_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_group_optional(const H5VL_object_t *vol_obj, H5VL_group_optional_t opt_type, hid_t dxpl_id, void **req,
                      ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value = H5VL__group_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req,
                                            arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_optional
   *
   * Purpose:     Performs an optional connector-specific operation on a group
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLgroup_optional(void *obj, hid_t connector_id, H5VL_group_optional_t opt_type, hid_t dxpl_id, void **req,
                     va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVwi**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__group_optional(obj, cls, opt_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute group optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__group_close
   *
   * Purpose:     Closes a group through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__group_close(void *obj, const H5VL_class_t *cls, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->group_cls.close)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'group close' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->group_cls.close)(obj, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "group close failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__group_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_group_close
   *
   * Purpose:     Closes a group through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_group_close(const H5VL_object_t *vol_obj, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__group_close(vol_obj->data, vol_obj->connector->cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "group close failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_group_close() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLgroup_close
   *
   * Purpose:     Closes a group
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLgroup_close(void *obj, hid_t connector_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xii**x", obj, connector_id, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__group_close(obj, cls, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCLOSEOBJ, FAIL, "unable to close group")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLgroup_close() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_create
   *
   * Purpose:	Creates a link through the VOL
   *
   * Note:	The 'obj' parameter is allowed to be NULL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_create(H5VL_link_create_type_t create_type, void *obj, const H5VL_loc_params_t *loc_params,
                    const H5VL_class_t *cls, hid_t lcpl_id, hid_t lapl_id, hid_t dxpl_id, void **req,
                    va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.create)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link create' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->link_cls.create)(create_type, obj, loc_params, lcpl_id, lapl_id, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, FAIL, "link create failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_create
   *
   * Purpose:	Creates a link through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_create(H5VL_link_create_type_t create_type, const H5VL_object_t *vol_obj,
                   const H5VL_loc_params_t *loc_params, hid_t lcpl_id, hid_t lapl_id, hid_t dxpl_id, void **req,
                   ...)
  {
      H5VL_object_t tmp_vol_obj;               /* Temporary object */
      va_list       arguments;                 /* Argument list passed from the API call */
      hbool_t       arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t       vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t        ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Start the varargs, so they can be copied */
      HDva_start(arguments, req);
      arg_started = TRUE;
  
      /* Special case for hard links */
      if (H5VL_LINK_CREATE_HARD == create_type && NULL == vol_obj->data) {
          va_list tmp_arguments; /* Copy of argument list passed in */
  
          /* Get the VOL data pointer from the varargs */
          HDva_copy(tmp_arguments, arguments);
          tmp_vol_obj.data = HDva_arg(tmp_arguments, void *);
          HDva_end(tmp_arguments);
      } /* end if */
      else
          /* Use the VOL object passed in */
          tmp_vol_obj.data = vol_obj->data;
      tmp_vol_obj.connector = vol_obj->connector;
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(&tmp_vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_create(create_type, vol_obj->data, loc_params, vol_obj->connector->cls, lcpl_id, lapl_id,
                            dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, FAIL, "link create failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_create() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_create
   *
   * Purpose:     Creates a link
   *
   * Note:	The 'obj' parameter is allowed to be NULL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_create(H5VL_link_create_type_t create_type, void *obj, const H5VL_loc_params_t *loc_params,
                  hid_t connector_id, hid_t lcpl_id, hid_t lapl_id, hid_t dxpl_id, void **req,
                  va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE9("e", "Vk*x*xiiii**xx", create_type, obj, loc_params, connector_id, lcpl_id, lapl_id, dxpl_id,
               req, arguments);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_create(create_type, obj, loc_params, cls, lcpl_id, lapl_id, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCREATE, FAIL, "unable to create link")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_create() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_copy
   *
   * Purpose:	Copys a link from src to dst.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_copy(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                  const H5VL_loc_params_t *loc_params2, const H5VL_class_t *cls, hid_t lcpl_id, hid_t lapl_id,
                  hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.copy)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link copy' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->link_cls.copy)(src_obj, loc_params1, dst_obj, loc_params2, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "link copy failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_copy
   *
   * Purpose:	Copys a link from src to dst.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_copy(const H5VL_object_t *src_vol_obj, const H5VL_loc_params_t *loc_params1,
                 const H5VL_object_t *dst_vol_obj, const H5VL_loc_params_t *loc_params2, hid_t lcpl_id,
                 hid_t lapl_id, hid_t dxpl_id, void **req)
  {
      const H5VL_object_t *vol_obj;                   /* VOL object for object with data */
      hbool_t              vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t               ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      vol_obj = (src_vol_obj->data ? src_vol_obj : dst_vol_obj);
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_copy(src_vol_obj->data, loc_params1, (dst_vol_obj ? dst_vol_obj->data : NULL), loc_params2,
                          vol_obj->connector->cls, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "link copy failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_copy
   *
   * Purpose:     Copies a link to a new location
   *
   * Note:	The 'src_obj' and 'dst_obj' parameters are allowed to be NULL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_copy(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                const H5VL_loc_params_t *loc_params2, hid_t connector_id, hid_t lcpl_id, hid_t lapl_id,
                hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE9("e", "*x*x*x*xiiii**x", src_obj, loc_params1, dst_obj, loc_params2, connector_id, lcpl_id,
               lapl_id, dxpl_id, req);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_copy(src_obj, loc_params1, dst_obj, loc_params2, cls, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "unable to copy object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_move
   *
   * Purpose:	Moves a link from src to dst.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_move(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                  const H5VL_loc_params_t *loc_params2, const H5VL_class_t *cls, hid_t lcpl_id, hid_t lapl_id,
                  hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.move)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link move' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->link_cls.move)(src_obj, loc_params1, dst_obj, loc_params2, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTMOVE, FAIL, "link move failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_move() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_move
   *
   * Purpose:	Moves a link from src to dst.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_move(const H5VL_object_t *src_vol_obj, const H5VL_loc_params_t *loc_params1,
                 const H5VL_object_t *dst_vol_obj, const H5VL_loc_params_t *loc_params2, hid_t lcpl_id,
                 hid_t lapl_id, hid_t dxpl_id, void **req)
  {
      const H5VL_object_t *vol_obj;                   /* VOL object for object with data */
      hbool_t              vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t               ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      vol_obj = (src_vol_obj->data ? src_vol_obj : dst_vol_obj);
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_move(src_vol_obj->data, loc_params1, (dst_vol_obj ? dst_vol_obj->data : NULL), loc_params2,
                          vol_obj->connector->cls, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTMOVE, FAIL, "link move failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_move() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_move
   *
   * Purpose:     Moves a link to another location
   *
   * Note:	The 'src_obj' and 'dst_obj' parameters are allowed to be NULL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_move(void *src_obj, const H5VL_loc_params_t *loc_params1, void *dst_obj,
                const H5VL_loc_params_t *loc_params2, hid_t connector_id, hid_t lcpl_id, hid_t lapl_id,
                hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE9("e", "*x*x*x*xiiii**x", src_obj, loc_params1, dst_obj, loc_params2, connector_id, lcpl_id,
               lapl_id, dxpl_id, req);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_move(src_obj, loc_params1, dst_obj, loc_params2, cls, lcpl_id, lapl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTMOVE, FAIL, "unable to move object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_move() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_get
   *
   * Purpose:	Get specific information about the link through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_get(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                 H5VL_link_get_t get_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->link_cls.get)(obj, loc_params, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "link get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_get
   *
   * Purpose:	Get specific information about the link through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_get(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, H5VL_link_get_t get_type,
                hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__link_get(vol_obj->data, loc_params, vol_obj->connector->cls, get_type, dxpl_id, req,
                         arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "link get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_get
   *
   * Purpose:     Gets information about a link
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_get(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, H5VL_link_get_t get_type,
               hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("e", "*x*xiVli**xx", obj, loc_params, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_get(obj, loc_params, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute link get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_specific
   *
   * Purpose:	Specific operation on links through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                      H5VL_link_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link specific' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->link_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_specific
   *
   * Purpose:	Specific operation on links through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_specific(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params,
                     H5VL_link_specific_t specific_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value = H5VL__link_specific(vol_obj->data, loc_params, vol_obj->connector->cls, specific_type,
                                           dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_specific
   *
   * Purpose:     Performs a connector-specific operation on a link
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_specific(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id,
                    H5VL_link_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("e", "*x*xiVmi**xx", obj, loc_params, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__link_specific(obj, loc_params, cls, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__link_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__link_optional(void *obj, const H5VL_class_t *cls, H5VL_link_optional_t opt_type, hid_t dxpl_id,
                      void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->link_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'link optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->link_cls.optional)(obj, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__link_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_link_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_link_optional(const H5VL_object_t *vol_obj, H5VL_link_optional_t opt_type, hid_t dxpl_id, void **req,
                     ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__link_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_link_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLlink_optional
   *
   * Purpose:     Performs an optional connector-specific operation on a link
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLlink_optional(void *obj, hid_t connector_id, H5VL_link_optional_t opt_type, hid_t dxpl_id, void **req,
                    va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVxi**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__link_optional(obj, cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute link optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLlink_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__object_open
   *
   * Purpose:	Opens a object through the VOL
   *
   * Return:      Success: Pointer to the object
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  static void *
  H5VL__object_open(void *obj, const H5VL_loc_params_t *params, const H5VL_class_t *cls,
                    H5I_type_t *opened_type, hid_t dxpl_id, void **req)
  {
      void *ret_value = NULL; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.open)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, NULL, "VOL connector has no 'object open' method")
  
      /* Call the corresponding VOL callback */
      if (NULL == (ret_value = (cls->object_cls.open)(obj, params, opened_type, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "object open failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__object_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_object_open
   *
   * Purpose:	Opens a object through the VOL
   *
   * Return:      Success: Pointer to the object
   *		Failure: NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VL_object_open(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *params, H5I_type_t *opened_type,
                   hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE; /* Whether the VOL object wrapping context was set up */
      void *  ret_value       = NULL;  /* Return value */
  
      FUNC_ENTER_NOAPI(NULL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, NULL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__object_open(vol_obj->data, params, vol_obj->connector->cls, opened_type,
                                                 dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "object open failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, NULL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_object_open() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLobject_open
   *
   * Purpose:     Opens an object
   *
   * Return:      Success:    Pointer to the object
   *              Failure:    NULL
   *
   *-------------------------------------------------------------------------
   */
  void *
  H5VLobject_open(void *obj, const H5VL_loc_params_t *params, hid_t connector_id, H5I_type_t *opened_type,
                  hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;              /* VOL connector's class struct */
      void *        ret_value = NULL; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("*x", "*x*xi*Iti**x", obj, params, connector_id, opened_type, dxpl_id, req);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (NULL == (ret_value = H5VL__object_open(obj, params, cls, opened_type, dxpl_id, req)))
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPENOBJ, NULL, "unable to open object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLobject_open() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__object_copy
   *
   * Purpose:	Copies an object to another destination through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__object_copy(void *src_obj, const H5VL_loc_params_t *src_loc_params, const char *src_name, void *dst_obj,
                    const H5VL_loc_params_t *dst_loc_params, const char *dst_name, const H5VL_class_t *cls,
                    hid_t ocpypl_id, hid_t lcpl_id, hid_t dxpl_id, void **req)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.copy)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'object copy' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->object_cls.copy)(src_obj, src_loc_params, src_name, dst_obj, dst_loc_params, dst_name,
                                 ocpypl_id, lcpl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "object copy failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__object_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_object_copy
   *
   * Purpose:	Copies an object to another destination through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_object_copy(const H5VL_object_t *src_obj, const H5VL_loc_params_t *src_loc_params, const char *src_name,
                   const H5VL_object_t *dst_obj, const H5VL_loc_params_t *dst_loc_params, const char *dst_name,
                   hid_t ocpypl_id, hid_t lcpl_id, hid_t dxpl_id, void **req)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Make sure that the VOL connectors are the same */
      if (src_obj->connector->cls->value != dst_obj->connector->cls->value)
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "objects are accessed through different VOL connectors and can't be copied")
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(src_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__object_copy(src_obj->data, src_loc_params, src_name, dst_obj->data, dst_loc_params, dst_name,
                            src_obj->connector->cls, ocpypl_id, lcpl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "object copy failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_object_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLobject_copy
   *
   * Purpose:     Copies an object to another location
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLobject_copy(void *src_obj, const H5VL_loc_params_t *src_loc_params, const char *src_name, void *dst_obj,
                  const H5VL_loc_params_t *dst_loc_params, const char *dst_name, hid_t connector_id,
                  hid_t ocpypl_id, hid_t lcpl_id, hid_t dxpl_id, void **req)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE11("e", "*x*x*s*x*x*siiii**x", src_obj, src_loc_params, src_name, dst_obj, dst_loc_params,
                dst_name, connector_id, ocpypl_id, lcpl_id, dxpl_id, req);
  
      /* Check args and get class pointers */
      if (NULL == src_obj || NULL == dst_obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__object_copy(src_obj, src_loc_params, src_name, dst_obj, dst_loc_params, dst_name, cls,
                            ocpypl_id, lcpl_id, dxpl_id, req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOPY, FAIL, "unable to copy object")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLobject_copy() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__object_get
   *
   * Purpose:	Get specific information about the object through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__object_get(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                   H5VL_object_get_t get_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'object get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->object_cls.get)(obj, loc_params, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "get failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__object_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_object_get
   *
   * Purpose:	Get specific information about the object through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_object_get(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params, H5VL_object_get_t get_type,
                  hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__object_get(vol_obj->data, loc_params, vol_obj->connector->cls, get_type, dxpl_id, req,
                           arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "get failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_object_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLobject_get
   *
   * Purpose:     Gets information about an object
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLobject_get(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id, H5VL_object_get_t get_type,
                 hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("e", "*x*xiVni**xx", obj, loc_params, connector_id, get_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__object_get(obj, loc_params, cls, get_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "unable to execute object get callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLobject_get() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__object_specific
   *
   * Purpose:	Specific operation on objects through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__object_specific(void *obj, const H5VL_loc_params_t *loc_params, const H5VL_class_t *cls,
                        H5VL_object_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'object specific' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->object_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "object specific failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__object_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_object_specific
   *
   * Purpose:	Specific operation on objects through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_object_specific(const H5VL_object_t *vol_obj, const H5VL_loc_params_t *loc_params,
                       H5VL_object_specific_t specific_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value = H5VL__object_specific(vol_obj->data, loc_params, vol_obj->connector->cls, specific_type,
                                             dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "object specific failed")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_object_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLobject_specific
   *
   * Purpose:     Performs a connector-specific operation on an object
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLobject_specific(void *obj, const H5VL_loc_params_t *loc_params, hid_t connector_id,
                      H5VL_object_specific_t specific_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE7("e", "*x*xiVoi**xx", obj, loc_params, connector_id, specific_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no `object specific' method")
  
      /* Bypass the H5VLint layer, calling the VOL callback directly */
      if ((ret_value = (cls->object_cls.specific)(obj, loc_params, specific_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLobject_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__object_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__object_optional(void *obj, const H5VL_class_t *cls, H5VL_object_optional_t opt_type, hid_t dxpl_id,
                        void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->object_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'object optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->object_cls.optional)(obj, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__object_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL_object_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_object_optional(const H5VL_object_t *vol_obj, H5VL_object_optional_t opt_type, hid_t dxpl_id, void **req,
                       ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if (H5VL__object_optional(vol_obj->data, vol_obj->connector->cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_object_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLobject_optional
   *
   * Purpose:     Performs an optional connector-specific operation on an object
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLobject_optional(void *obj, hid_t connector_id, H5VL_object_optional_t opt_type, hid_t dxpl_id, void **req,
                      va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiVyi**xx", obj, connector_id, opt_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__object_optional(obj, cls, opt_type, dxpl_id, req, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute object optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLobject_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__introspect_get_conn_cls
   *
   * Purpose:     Calls the connector-specific callback to query the connector
   *              class.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__introspect_get_conn_cls(void *obj, const H5VL_class_t *cls, H5VL_get_conn_lvl_t lvl,
                                const H5VL_class_t **conn_cls)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
      HDassert(lvl >= H5VL_GET_CONN_LVL_CURR && lvl <= H5VL_GET_CONN_LVL_TERM);
      HDassert(conn_cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->introspect_cls.get_conn_cls)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'get_conn_cls' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->introspect_cls.get_conn_cls)(obj, lvl, conn_cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query connector class")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__introspect_get_conn_cls() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_introspect_get_conn_cls
   *
   * Purpose:     Calls the connector-specific callback to query the connector
   *              class.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_introspect_get_conn_cls(const H5VL_object_t *vol_obj, H5VL_get_conn_lvl_t lvl,
                               const H5VL_class_t **conn_cls)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__introspect_get_conn_cls(vol_obj->data, vol_obj->connector->cls, lvl, conn_cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query connector class")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_introspect_get_conn_cls() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLintrospect_get_conn_cls
   *
   * Purpose:     Calls the connector-specific callback to query the connector
   *              class.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLintrospect_get_conn_cls(void *obj, hid_t connector_id, H5VL_get_conn_lvl_t lvl,
                              const H5VL_class_t **conn_cls)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xiVL**x", obj, connector_id, lvl, conn_cls);
  
      /* Check args */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "NULL obj pointer")
      if (NULL == conn_cls)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "NULL conn_cls pointer")
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__introspect_get_conn_cls(obj, cls, lvl, conn_cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query connector class")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLintrospect_get_conn_cls() */
  
  /*-------------------------------------------------------------------------
   * Function:	H5VL__introspect_opt_query
   *
   * Purpose:     Calls the connector-specific callback to query if an optional
   *              operation is supported.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__introspect_opt_query(void *obj, const H5VL_class_t *cls, H5VL_subclass_t subcls, int opt_type,
                             hbool_t *supported)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->introspect_cls.opt_query)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'opt_query' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->introspect_cls.opt_query)(obj, subcls, opt_type, supported) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query optional operation support")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__introspect_opt_query() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_introspect_opt_query
   *
   * Purpose:     Calls the connector-specific callback to query if an optional
   *              operation is supported.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_introspect_opt_query(const H5VL_object_t *vol_obj, H5VL_subclass_t subcls, int opt_type,
                            hbool_t *supported)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__introspect_opt_query(vol_obj->data, vol_obj->connector->cls, subcls, opt_type, supported) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query optional operation support")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_introspect_opt_query() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLintrospect_opt_query
   *
   * Purpose:     Calls the connector-specific callback to query if an optional
   *              operation is supported.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLintrospect_opt_query(void *obj, hid_t connector_id, H5VL_subclass_t subcls, int opt_type,
                           hbool_t *supported)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xiVSIs*b", obj, connector_id, subcls, opt_type, supported);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__introspect_opt_query(obj, cls, subcls, opt_type, supported) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "can't query optional operation support")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLintrospect_opt_query() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_wait
   *
   * Purpose:     Waits on an asychronous request through the VOL
   *
   * Note:	Releases the request if the operation has completed and the
   *		connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_wait(void *req, const H5VL_class_t *cls, uint64_t timeout, H5ES_status_t *status)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity checks */
      HDassert(req);
      HDassert(cls);
      HDassert(status);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.wait)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async wait' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->request_cls.wait)(req, timeout, status) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request wait failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_wait() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_wait
   *
   * Purpose:     Waits on an asychronous request through the VOL
   *
   * Note:	Releases the request if the operation has completed and the
   *		connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_wait(const H5VL_object_t *vol_obj, uint64_t timeout, H5ES_status_t *status)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_wait(vol_obj->data, vol_obj->connector->cls, timeout, status) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request wait failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_wait() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_wait
   *
   * Purpose:     Waits on a request
   *
   * Note:	Releases the request if the operation has completed and the
   *		connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_wait(void *req, hid_t connector_id, uint64_t timeout, H5ES_status_t *status)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xiUL*Es", req, connector_id, timeout, status);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_wait(req, cls, timeout, status) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "unable to wait on request")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_wait() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_notify
   *
   * Purpose:     Registers a user callback to be invoked when an asynchronous
   *		operation completes
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_notify(void *req, const H5VL_class_t *cls, H5VL_request_notify_t cb, void *ctx)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(req);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.notify)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async notify' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->request_cls.notify)(req, cb, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request notify failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_notify() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_notify
   *
   * Purpose:     Registers a user callback to be invoked when an asynchronous
   *		operation completes
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_notify(const H5VL_object_t *vol_obj, H5VL_request_notify_t cb, void *ctx)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_notify(vol_obj->data, vol_obj->connector->cls, cb, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "request notify failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_notify() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_notify
   *
   * Purpose:     Registers a user callback to be invoked when an asynchronous
   *		operation completes
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_notify(void *req, hid_t connector_id, H5VL_request_notify_t cb, void *ctx)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xix*x", req, connector_id, cb, ctx);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_notify(req, cls, cb, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "unable to register notify callback for request")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_notify() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_cancel
   *
   * Purpose:     Cancels an asynchronous request through the VOL
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_cancel(void *req, const H5VL_class_t *cls)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(req);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.cancel)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async cancel' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->request_cls.cancel)(req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request cancel failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_cancel() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_cancel
   *
   * Purpose:     Cancels an asynchronous request through the VOL
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_cancel(const H5VL_object_t *vol_obj)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_cancel(vol_obj->data, vol_obj->connector->cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request cancel failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_cancel() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_cancel
   *
   * Purpose:     Cancels a request
   *
   * Note:	Releases the request, if connector callback succeeds
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_cancel(void *req, hid_t connector_id)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "*xi", req, connector_id);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_cancel(req, cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "unable to cancel request")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_cancel() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_specific
   *
   * Purpose:	Specific operation on asynchronous request through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_specific(void *req, const H5VL_class_t *cls, H5VL_request_specific_t specific_type,
                         va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(req);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async specific' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->request_cls.specific)(req, specific_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_specific
   *
   * Purpose:	Specific operation on asynchronous request through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_specific(const H5VL_object_t *vol_obj, H5VL_request_specific_t specific_type, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, specific_type);
      arg_started = TRUE;
      if ((ret_value =
               H5VL__request_specific(vol_obj->data, vol_obj->connector->cls, specific_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_specific
   *
   * Purpose:     Performs a connector-specific operation on an asynchronous request
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_specific(void *req, hid_t connector_id, H5VL_request_specific_t specific_type, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xiVrx", req, connector_id, specific_type, arguments);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__request_specific(req, cls, specific_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request specific callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_optional(void *req, const H5VL_class_t *cls, H5VL_request_optional_t opt_type,
                         va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(req);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async optional' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->request_cls.optional)(req, opt_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_optional
   *
   * Purpose:	Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_optional(const H5VL_object_t *vol_obj, H5VL_request_optional_t opt_type, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, opt_type);
      arg_started = TRUE;
      if ((ret_value = H5VL__request_optional(vol_obj->data, vol_obj->connector->cls, opt_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_optional
   *
   * Purpose:     Performs an optional connector-specific operation on an asynchronous request
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_optional(void *req, hid_t connector_id, H5VL_request_optional_t opt_type, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE4("e", "*xiVzx", req, connector_id, opt_type, arguments);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__request_optional(req, cls, opt_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL,
                      "unable to execute asynchronous request optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__request_free
   *
   * Purpose:     Frees an asynchronous request through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__request_free(void *req, const H5VL_class_t *cls)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(req);
      HDassert(cls);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->request_cls.free)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'async free' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->request_cls.free)(req) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request free failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__request_free() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_request_free
   *
   * Purpose:     Frees an asynchronous request through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_request_free(const H5VL_object_t *vol_obj)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding VOL callback */
      if (H5VL__request_free(vol_obj->data, vol_obj->connector->cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "request free failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_request_free() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLrequest_free
   *
   * Purpose:     Frees a request
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLrequest_free(void *req, hid_t connector_id)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE2("e", "*xi", req, connector_id);
  
      /* Get class pointer */
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__request_free(req, cls) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTRELEASE, FAIL, "unable to free request")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLrequest_free() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__blob_put
   *
   * Purpose:     Put a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__blob_put(void *obj, const H5VL_class_t *cls, const void *buf, size_t size, void *blob_id, void *ctx)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
      HDassert(size == 0 || buf);
      HDassert(blob_id);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->blob_cls.put)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'blob put' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->blob_cls.put)(obj, buf, size, blob_id, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "blob put callback failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__blob_put() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_blob_put
   *
   * Purpose:     Put a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   * Programmer:	Quincey Koziol
   *		Wednesday, August 21, 2019
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_blob_put(const H5VL_object_t *vol_obj, const void *buf, size_t size, void *blob_id, void *ctx)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
      HDassert(size == 0 || buf);
      HDassert(blob_id);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_put(vol_obj->data, vol_obj->connector->cls, buf, size, blob_id, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "blob put failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_blob_put() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLblob_put
   *
   * Purpose:     Put a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLblob_put(void *obj, hid_t connector_id, const void *buf, size_t size, void *blob_id, void *ctx)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xi*xz*x*x", obj, connector_id, buf, size, blob_id, ctx);
  
      /* Get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_put(obj, cls, buf, size, blob_id, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "blob put failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLblob_put() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__blob_get
   *
   * Purpose:     Get a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__blob_get(void *obj, const H5VL_class_t *cls, const void *blob_id, void *buf, size_t size, void *ctx)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
      HDassert(blob_id);
      HDassert(buf);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->blob_cls.get)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'blob get' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->blob_cls.get)(obj, blob_id, buf, size, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "blob get callback failed")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__blob_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_blob_get
   *
   * Purpose:     Get a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_blob_get(const H5VL_object_t *vol_obj, const void *blob_id, void *buf, size_t size, void *ctx)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
      HDassert(blob_id);
      HDassert(buf);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_get(vol_obj->data, vol_obj->connector->cls, blob_id, buf, size, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "blob get failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_blob_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLblob_get
   *
   * Purpose:     Get a blob through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLblob_get(void *obj, hid_t connector_id, const void *blob_id, void *buf, size_t size, void *ctx)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xi*x*xz*x", obj, connector_id, blob_id, buf, size, ctx);
  
      /* Get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_get(obj, cls, blob_id, buf, size, ctx) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTGET, FAIL, "blob get failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLblob_get() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__blob_specific
   *
   * Purpose:	Specific operation on blobs through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   * Programmer:	Quincey Koziol
   *		Saturday, August 17, 2019
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__blob_specific(void *obj, const H5VL_class_t *cls, void *blob_id, H5VL_blob_specific_t specific_type,
                      va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
      HDassert(blob_id);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->blob_cls.specific)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'blob specific' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->blob_cls.specific)(obj, blob_id, specific_type, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute blob specific callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__blob_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_blob_specific
   *
   * Purpose: Specific operation on blobs through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_blob_specific(const H5VL_object_t *vol_obj, void *blob_id, H5VL_blob_specific_t specific_type, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
      HDassert(blob_id);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, specific_type);
      arg_started = TRUE;
      if ((ret_value = H5VL__blob_specific(vol_obj->data, vol_obj->connector->cls, blob_id, specific_type,
                                           arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute blob specific callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_blob_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLblob_specific
   *
   * Purpose: Specific operation on blobs through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLblob_specific(void *obj, hid_t connector_id, void *blob_id, H5VL_blob_specific_t specific_type,
                    va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xi*xVBx", obj, connector_id, blob_id, specific_type, arguments);
  
      /* Get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_specific(obj, cls, blob_id, specific_type, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "blob specific operation failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLblob_specific() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__blob_optional
   *
   * Purpose:	Optional operation on blobs through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   * Programmer:	Quincey Koziol
   *		Thursday, November 14, 2019
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__blob_optional(void *obj, const H5VL_class_t *cls, void *blob_id, H5VL_blob_optional_t opt_type,
                      va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity check */
      HDassert(obj);
      HDassert(cls);
      HDassert(blob_id);
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->blob_cls.optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'blob optional' method")
  
      /* Call the corresponding VOL callback */
      if ((cls->blob_cls.optional)(obj, blob_id, opt_type, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute blob optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__blob_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_blob_optional
   *
   * Purpose: Optional operation on blobs through the VOL
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_blob_optional(const H5VL_object_t *vol_obj, void *blob_id, H5VL_blob_optional_t opt_type, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity check */
      HDassert(vol_obj);
      HDassert(blob_id);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, opt_type);
      arg_started = TRUE;
      if ((ret_value =
               H5VL__blob_optional(vol_obj->data, vol_obj->connector->cls, blob_id, opt_type, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute blob optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_blob_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLblob_optional
   *
   * Purpose: Optional operation on blobs through the VOL
   *
   * Return:      SUCCEED / FAIL
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLblob_optional(void *obj, hid_t connector_id, void *blob_id, H5VL_blob_optional_t opt_type,
                    va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xi*xVAx", obj, connector_id, blob_id, opt_type, arguments);
  
      /* Get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding VOL callback */
      if (H5VL__blob_optional(obj, cls, blob_id, opt_type, arguments) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "blob optional operation failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLblob_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__token_cmp
   *
   * Purpose:     Compares two VOL connector object tokens. Sets *cmp_value
   *              to positive if token1 is greater than token2, negative if
   *              token2 is greater than token1 and zero if token1 and
   *              token2 are equal.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__token_cmp(void *obj, const H5VL_class_t *cls, const H5O_token_t *token1, const H5O_token_t *token2,
                  int *cmp_value)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity checks */
      HDassert(obj);
      HDassert(cls);
      HDassert(cmp_value);
  
      /* Take care of cases where one or both pointers is NULL */
      if (token1 == NULL && token2 != NULL)
          *cmp_value = -1;
      else if (token1 != NULL && token2 == NULL)
          *cmp_value = 1;
      else if (token1 == NULL && token2 == NULL)
          *cmp_value = 0;
      else {
          /* Use the class's token comparison routine to compare the tokens,
           * if there is a callback, otherwise just compare the tokens as
           * memory buffers.
           */
          if (cls->token_cls.cmp) {
              if ((cls->token_cls.cmp)(obj, token1, token2, cmp_value) < 0)
                  HGOTO_ERROR(H5E_VOL, H5E_CANTCOMPARE, FAIL, "can't compare object tokens")
          } /* end if */
          else
              *cmp_value = HDmemcmp(token1, token2, sizeof(H5O_token_t));
      } /* end else */
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__token_cmp() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_token_cmp
   *
   * Purpose:     Compares two VOL connector object tokens. Sets *cmp_value
   *              to positive if token1 is greater than token2, negative if
   *              token2 is greater than token1 and zero if token1 and
   *              token2 are equal.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_token_cmp(const H5VL_object_t *vol_obj, const H5O_token_t *token1, const H5O_token_t *token2,
                 int *cmp_value)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(vol_obj);
      HDassert(cmp_value);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__token_cmp(vol_obj->data, vol_obj->connector->cls, token1, token2, cmp_value)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOMPARE, FAIL, "token compare failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_token_cmp() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLtoken_cmp
   *
   * Purpose:     Compares two VOL connector object tokens
   *
   * Note:        Both object tokens must be from the same VOL connector class
   *
   * Return:      Success:    Non-negative, with *cmp_value set to positive if
   *                          token1 is greater than token2, negative if token2
   *                          is greater than token1 and zero if token1 and
   *                          token2 are equal.
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLtoken_cmp(void *obj, hid_t connector_id, const H5O_token_t *token1, const H5O_token_t *token2,
                int *cmp_value)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xi*k*k*Is", obj, connector_id, token1, token2, cmp_value);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
      if (NULL == cmp_value)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid cmp_value pointer")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__token_cmp(obj, cls, token1, token2, cmp_value) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTCOMPARE, FAIL, "object token comparison failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLtoken_cmp() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__token_to_str
   *
   * Purpose:     Serialize a connector's object token into a string
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__token_to_str(void *obj, H5I_type_t obj_type, const H5VL_class_t *cls, const H5O_token_t *token,
                     char **token_str)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity checks */
      HDassert(obj);
      HDassert(cls);
      HDassert(token);
      HDassert(token_str);
  
      /* Use the class's token serialization routine on the token if there is a
       *  callback, otherwise just set the token_str to NULL.
       */
      if (cls->token_cls.to_str) {
          if ((cls->token_cls.to_str)(obj, obj_type, token, token_str) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTSERIALIZE, FAIL, "can't serialize object token")
      } /* end if */
      else
          *token_str = NULL;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__token_to_str() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_token_to_str
   *
   * Purpose:     Serialize a connector's object token into a string
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_token_to_str(const H5VL_object_t *vol_obj, H5I_type_t obj_type, const H5O_token_t *token,
                    char **token_str)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(vol_obj);
      HDassert(token);
      HDassert(token_str);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__token_to_str(vol_obj->data, obj_type, vol_obj->connector->cls, token, token_str)) <
          0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSERIALIZE, FAIL, "token serialization failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_token_to_str() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLtoken_to_str
   *
   * Purpose:     Serialize a connector's object token into a string
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLtoken_to_str(void *obj, H5I_type_t obj_type, hid_t connector_id, const H5O_token_t *token,
                   char **token_str)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xIti*k**s", obj, obj_type, connector_id, token, token_str);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
      if (NULL == token)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid token pointer")
      if (NULL == token_str)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid token_str pointer")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__token_to_str(obj, obj_type, cls, token, token_str) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSERIALIZE, FAIL, "object token to string failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLtoken_to_str() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__token_from_str
   *
   * Purpose:     Deserialize a string into a connector object token
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__token_from_str(void *obj, H5I_type_t obj_type, const H5VL_class_t *cls, const char *token_str,
                       H5O_token_t *token)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Sanity checks */
      HDassert(obj);
      HDassert(cls);
      HDassert(token_str);
      HDassert(token);
  
      /* Use the class's token deserialization routine on the token if there is a
       *  callback, otherwise just set the token to H5_TOKEN_UNDEF.
       */
      if (cls->token_cls.from_str) {
          if ((cls->token_cls.from_str)(obj, obj_type, token_str, token) < 0)
              HGOTO_ERROR(H5E_VOL, H5E_CANTUNSERIALIZE, FAIL, "can't deserialize object token string")
      } /* end if */
      else
          *token = H5O_TOKEN_UNDEF;
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__token_from_str() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_token_from_str
   *
   * Purpose:     Deserialize a string into a connector object token
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_token_from_str(const H5VL_object_t *vol_obj, H5I_type_t obj_type, const char *token_str,
                      H5O_token_t *token)
  {
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Sanity checks */
      HDassert(vol_obj);
      HDassert(token);
      HDassert(token_str);
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value =
               H5VL__token_from_str(vol_obj->data, obj_type, vol_obj->connector->cls, token_str, token)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTUNSERIALIZE, FAIL, "token deserialization failed")
  
  done:
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, FAIL, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_token_from_str() */
  
  /*---------------------------------------------------------------------------
   * Function:    H5VLtoken_from_str
   *
   * Purpose:     Deserialize a string into a connector object token
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *---------------------------------------------------------------------------
   */
  herr_t
  H5VLtoken_from_str(void *obj, H5I_type_t obj_type, hid_t connector_id, const char *token_str,
                     H5O_token_t *token)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE5("e", "*xIti*s*k", obj, obj_type, connector_id, token_str, token);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
      if (NULL == token)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid token pointer")
      if (NULL == token_str)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid token_str pointer")
  
      /* Call the corresponding internal VOL routine */
      if (H5VL__token_from_str(obj, obj_type, cls, token_str, token) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTUNSERIALIZE, FAIL, "object token from string failed")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLtoken_from_str() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL__optional
   *
   * Purpose:     Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  static herr_t
  H5VL__optional(void *obj, const H5VL_class_t *cls, int op_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      herr_t ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_STATIC
  
      /* Check if the corresponding VOL callback exists */
      if (NULL == cls->optional)
          HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "VOL connector has no 'optional' method")
  
      /* Call the corresponding VOL callback */
      if ((ret_value = (cls->optional)(obj, op_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, ret_value, "unable to execute optional callback")
  
  done:
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL__optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VL_optional
   *
   * Purpose:     Optional operation specific to connectors.
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VL_optional(const H5VL_object_t *vol_obj, int op_type, hid_t dxpl_id, void **req, ...)
  {
      va_list arguments;                 /* Argument list passed from the API call */
      hbool_t arg_started     = FALSE;   /* Whether the va_list has been started */
      hbool_t vol_wrapper_set = FALSE;   /* Whether the VOL object wrapping context was set up */
      herr_t  ret_value       = SUCCEED; /* Return value */
  
      FUNC_ENTER_NOAPI(FAIL)
  
      /* Set wrapper info in API context */
      if (H5VL_set_vol_wrapper(vol_obj) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTSET, FAIL, "can't set VOL wrapper info")
      vol_wrapper_set = TRUE;
  
      /* Call the corresponding internal VOL routine */
      HDva_start(arguments, req);
      arg_started = TRUE;
      if ((ret_value =
               H5VL__optional(vol_obj->data, vol_obj->connector->cls, op_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, FAIL, "unable to execute optional callback")
  
  done:
      /* End access to the va_list, if we started it */
      if (arg_started)
          HDva_end(arguments);
  
      /* Reset object wrapping info in API context */
      if (vol_wrapper_set && H5VL_reset_vol_wrapper() < 0)
          HDONE_ERROR(H5E_VOL, H5E_CANTRESET, ret_value, "can't reset VOL wrapper info")
  
      FUNC_LEAVE_NOAPI(ret_value)
  } /* end H5VL_optional() */
  
  /*-------------------------------------------------------------------------
   * Function:    H5VLoptional
   *
   * Purpose:     Performs an optional connector-specific operation
   *
   * Return:      Success:    Non-negative
   *              Failure:    Negative
   *
   *-------------------------------------------------------------------------
   */
  herr_t
  H5VLoptional(void *obj, hid_t connector_id, int op_type, hid_t dxpl_id, void **req, va_list arguments)
  {
      H5VL_class_t *cls;                 /* VOL connector's class struct */
      herr_t        ret_value = SUCCEED; /* Return value */
  
      FUNC_ENTER_API_NOINIT
      H5TRACE6("e", "*xiIsi**xx", obj, connector_id, op_type, dxpl_id, req, arguments);
  
      /* Check args and get class pointer */
      if (NULL == obj)
          HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid object")
      if (NULL == (cls = (H5VL_class_t *)H5I_object_verify(connector_id, H5I_VOL)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a VOL connector ID")
  
      /* Call the corresponding internal VOL routine */
      if ((ret_value = H5VL__optional(obj, cls, op_type, dxpl_id, req, arguments)) < 0)
          HGOTO_ERROR(H5E_VOL, H5E_CANTOPERATE, ret_value, "unable to execute optional callback")
  
  done:
      FUNC_LEAVE_API_NOINIT(ret_value)
  } /* end H5VLoptional() */
  