int
main (void)
{
    hid_t       file;           /* file handle */
    hid_t 	grp_a, grp_b, grp_c; /* group handlers */

    /*
     * Create a new file using H5F_ACC_TRUNC access,
     * default file creation properties, and default file
     * access properties.
     */
    file = H5Fcreate(H5FILE_NAME, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /*
     * Create groups in the file.
     */
    grp_a = H5Gcreate2(file,  "/a",     H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    grp_b = H5Gcreate2(grp_a, "b", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    grp_c = H5Gcreate2(grp_b, "c", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

    H5Gclose(grp_a);
    H5Gclose(grp_b);
    H5Gclose(grp_c);
    H5Fclose(file);

    return 0;
}

int main(){
  hid_t fprop;
  hid_t fid;
  hid_t vol_id = H5VL_memvol_init();
  herr_t status;

  hid_t g1, g2;
  hid_t plist;

  char name[1024];

  fprop = H5Pcreate(H5P_FILE_ACCESS);
  H5Pset_vol(fprop, vol_id, &fprop);

  fid = H5Fcreate("test", H5F_ACC_TRUNC, H5P_DEFAULT, fprop);
  H5VLget_plugin_name(fid, name, 1024);
  printf ("Using VOL %s\n", name);

  g1 = H5Gcreate2(fid, "g1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
  H5Gclose(g1);

  g2 = H5Gcreate2(fid, "g2", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
  g1 = H5Gcreate2(g2, "g1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
  H5Gclose(g1);
  H5Gclose(g2);

  // is this allowed?
  //g3 = H5Gcreate2(fid, "g1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
  //H5Gclose(g3);

  printf("Testing additional functions\n");
  g1 = H5Gopen2(fid, "g1", H5P_DEFAULT );
  plist = H5Gget_create_plist(g1);
  H5G_info_t group_info;
  H5Gget_info(g1, & group_info );

  H5Gget_info_by_idx(fid, "g1",  H5_INDEX_CRT_ORDER,  H5_ITER_NATIVE, 0, & group_info, H5P_DEFAULT ) ;
  H5Gget_info_by_idx(fid, "g1",  H5_INDEX_NAME,  H5_ITER_NATIVE, 0, & group_info, H5P_DEFAULT ) ;
  H5Gget_info_by_name(fid, "g1", & group_info, H5P_DEFAULT);
  H5Pclose(plist);

  status = H5Gclose(g1);
  g1 = H5Gopen2(fid, "g2", H5P_DEFAULT );
  H5Gclose(g1);
  //g1 = H5Gopen2(fid, "INVALID", H5P_DEFAULT );
  //H5Gclose(g1);

  g1 =  H5Gcreate_anon( fid, H5P_DEFAULT, H5P_DEFAULT );
  H5Gclose(g1);

  H5Fclose(fid);
  H5VL_memvol_finalize();


  printf("Status: %d\n", status);

  return 0;
}

/*-------------------------------------------------------------------------
 * Function:  test_creating_groups_using_plugins
 *
 * Purpose:   Tests creating group with dynamically loaded filters
 *
 * Return:    SUCCEED/FAIL
 *
 *-------------------------------------------------------------------------
 */
static herr_t
test_creating_groups_using_plugins(hid_t fid)
{
    hid_t    gcpl_id = -1;
    hid_t    gid = -1;
    hid_t    sub_gid = -1;
    int      i;
    char     subgroup_name[256];

    TESTING("creating groups with filter plugin 4");

    if ((gcpl_id = H5Pcreate(H5P_GROUP_CREATE)) < 0)
        TEST_ERROR;

    /* Use a filter plugin for creating groups */
    if (H5Pset_filter(gcpl_id, FILTER4_ID, H5Z_FLAG_MANDATORY, (size_t)0, NULL) < 0)
        TEST_ERROR;

    /* Create a group using this filter */
    if ((gid = H5Gcreate2(fid, TOP_LEVEL_GROUP_NAME, H5P_DEFAULT, gcpl_id, H5P_DEFAULT)) < 0)
        TEST_ERROR;

    /* Create multiple groups under the top-level group */
    for (i = 0; i < N_SUBGROUPS; i++) {
        char *sp = subgroup_name;

        sp += HDsprintf(subgroup_name, SUBGROUP_PREFIX);
        HDsprintf(sp, "%d", i);

        if ((sub_gid = H5Gcreate2(gid, subgroup_name, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
            TEST_ERROR;
        if (H5Gclose(sub_gid) < 0)
            TEST_ERROR;
    }

    /* Close everything */
    if (H5Gclose(gid) < 0)
        TEST_ERROR;
    if (H5Pclose(gcpl_id) < 0)
        TEST_ERROR;

    PASSED();

    return SUCCEED;

error:
    /* Clean up objects used for this test */
    H5E_BEGIN_TRY {
        H5Gclose(sub_gid);
        H5Gclose(gid);
        H5Pclose(gcpl_id);
    } H5E_END_TRY

    return FAIL;
} /* end test_creating_groups_using_plugins() */

int
main (void)
{
  hid_t fid1=-1;
  hid_t fid2=-1;
  hid_t gid=-1;
  char filename1[NAME_BUF_SIZE];
  char filename2[NAME_BUF_SIZE];

  /* Name the files differently depending on the endianness of this platform */

  switch(H5Tget_order(H5T_NATIVE_INT))
  {
    case H5T_ORDER_LE:
      strcpy(filename1, NAME_LE_1);
      strcpy(filename2, NAME_LE_2);
      break;
    case H5T_ORDER_BE:
      strcpy(filename1, NAME_BE_1);
      strcpy(filename2, NAME_BE_2);
      break;
    default:
      goto error;
  }

  /* Create the two files */
  if((fid1 = H5Fcreate(filename1, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;
  if((fid2 = H5Fcreate(filename2, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;

  /* Create two groups in the second file */
  if((gid = H5Gcreate2(fid2, "group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;
  if((H5Gclose(gid)) < 0) goto error;
  if((gid = H5Gcreate2(fid2, "group/subgroup", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;
  if((H5Gclose(gid)) < 0) goto error;

  /* Create an external link in the first file pointing to the group in the second file */
  if(H5Lcreate_external(filename2, "group", fid1, "ext_link", H5P_DEFAULT, H5P_DEFAULT) < 0) goto error;

  if((H5Fclose(fid1)) < 0) goto error;
  if((H5Fclose(fid2)) < 0) goto error;

  return 0;

error:
  H5E_BEGIN_TRY {
    H5Fclose(fid1);
    H5Fclose(fid2);
    H5Gclose(gid);
  } H5E_END_TRY
  return 1;
}

/** 
 * Create an HDF5 file. 
 */
static hid_t _hdf_create(const char *path, int cmode)
{
  hid_t grp_id;
  hid_t fd;
  hid_t tmp_id;
  hid_t hdf_gpid;
  hid_t fpid;
  
  fpid = H5Pcreate (H5P_FILE_ACCESS);
  
  /*VF use all the features of new HDF5 1.8*/
  H5Pset_libver_bounds (fpid, H5F_LIBVER_18, H5F_LIBVER_18);
  
  H5E_BEGIN_TRY {
    fd = H5Fcreate(path, cmode, H5P_DEFAULT, fpid);
  } H5E_END_TRY;
  
  if (fd < 0) {
    /*TODO: report error properly*/
    return MI_LOG_ERROR(MI2_MSG_CREATEFILE,path);
  }
  
  /* Create the default groups.
   * Should we use a non-zero value for size_hint (parameter 3)???
   */

  hdf_gpid = H5Pcreate (H5P_GROUP_CREATE);
  H5Pset_attr_phase_change (hdf_gpid, 0, 0);
  
  MI_CHECK_HDF_CALL_RET(grp_id = H5Gcreate2(fd, MI_ROOT_PATH , H5P_DEFAULT, hdf_gpid, H5P_DEFAULT),"H5Gcreate2")

  MI_CHECK_HDF_CALL_RET(tmp_id = H5Gcreate2(grp_id, "dimensions", H5P_DEFAULT, hdf_gpid, H5P_DEFAULT),"H5Gcreate2")
  H5Gclose(tmp_id);
  
  MI_CHECK_HDF_CALL_RET(tmp_id = H5Gcreate2(grp_id, "info", H5P_DEFAULT, hdf_gpid, H5P_DEFAULT),"H5Gcreate2")
  H5Gclose(tmp_id);
  
  MI_CHECK_HDF_CALL_RET(tmp_id = H5Gcreate2(grp_id, "image", H5P_DEFAULT, hdf_gpid, H5P_DEFAULT),"H5Gcreate2")
  
  H5Gclose(tmp_id);
  MI_CHECK_HDF_CALL_RET(tmp_id = H5Gcreate2(grp_id, "image/0", H5P_DEFAULT, hdf_gpid, H5P_DEFAULT),"H5Gcreate2")
  
  H5Pclose ( hdf_gpid );
  H5Gclose(tmp_id);
  H5Gclose(grp_id);
  
  return fd;
}

/*-------------------------------------------------------------------------
 * Function:    create_file
 *
 * Purpose:    Creates file used in part 1 of the test
 *
 * Return:    Success:    0
 *
 *        Failure:    1
 *
 * Programmer:    Leon Arber
 *              Sept. 26, 2006
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static hid_t
create_file(char* name, hid_t fapl)
{
    hid_t    file, dcpl, space, dset, groups, grp, plist;
    hsize_t    ds_size[2] = {100, 100};
    hsize_t    ch_size[2] = {5, 5};
    hsize_t    i, j;



    if((file=H5Fcreate(name, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0) goto error;

    /* Create a chunked dataset */
    if((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0) goto error;
    if(H5Pset_chunk(dcpl, 2, ch_size) < 0) goto error;
    if((space = H5Screate_simple(2, ds_size, NULL)) < 0) goto error;
    if((dset = H5Dcreate2(file, "dset", H5T_NATIVE_FLOAT, space, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
    goto error;

    plist = H5Pcreate(H5P_DATASET_XFER);
    H5Pset_dxpl_mpio(plist, H5FD_MPIO_COLLECTIVE);


    /* Write some data */
    for(i = 0; i < ds_size[0]; i++) {
    /*
    * The extra cast in the following statement is a bug workaround
    * for the Win32 version 5.0 compiler.
    * 1998-11-06 ptl
    */
    for(j = 0; j < ds_size[1]; j++)
        the_data[i][j] = (double)(hssize_t)i/(hssize_t)(j+1);
    }
    if(H5Dwrite(dset, H5T_NATIVE_DOUBLE, space, space, plist, the_data) < 0) goto error;

    /* Create some groups */
    if((groups = H5Gcreate2(file, "some_groups", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;
    for(i = 0; i < 100; i++) {
    sprintf(name, "grp%02u", (unsigned)i);
    if((grp = H5Gcreate2(groups, name, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) goto error;
    if(H5Gclose(grp) < 0) goto error;
    }

    return file;

error:
    HD_exit(1);
}

  GWriteHDFFile::GWriteHDFFile(std::string filename, std::valarray<uint32_t> npart_in, std::vector<block_info>* BlockNames, bool format_2, bool debug) : GBaseWriteFile(filename, npart_in), debug(debug)
  {
          //Create file
          hid_t hdf_file = H5Fcreate(filename.c_str(),H5F_ACC_TRUNC,H5P_DEFAULT,H5P_DEFAULT);
          if(hdf_file < 0){
              throw  std::ios_base::failure(std::string("Unable to create file: ")+filename);
          }
          //Create groups in the file
          for(int i = 0; i < N_TYPE; i++){
                if(npart_in[i] == 0)
                    continue;
                snprintf(g_name[i], 20,"PartType%d",i);
                hid_t group = H5Gcreate2(hdf_file,g_name[i],H5P_DEFAULT, H5P_DEFAULT,H5P_DEFAULT);
                if (group < 0)
                    throw  std::ios_base::failure(std::string("Unable to create group: ")+std::string(g_name[i]));
          }
          //Create metadata about datablocks: we only actually use partlen.
          std::vector<block_info>::iterator it;
          for(it=(*BlockNames).begin(); it<(*BlockNames).end(); ++it){
              //Detect an integer type
              if ((*it).partlen == sizeof(int64_t))
                  m_ints.insert((*it).name);
          }
          return;

  }

void SGDSolver<Dtype>::SnapshotSolverStateToHDF5(
    const string& model_filename) {
#ifdef USE_HDF5
  string snapshot_filename =
      Solver<Dtype>::SnapshotFilename(".solverstate.h5");
  LOG(INFO) << "Snapshotting solver state to HDF5 file " << snapshot_filename;
  hid_t file_hid = H5Fcreate(snapshot_filename.c_str(), H5F_ACC_TRUNC,
      H5P_DEFAULT, H5P_DEFAULT);
  CHECK_GE(file_hid, 0)
      << "Couldn't open " << snapshot_filename << " to save solver state.";
  hdf5_save_int(file_hid, "iter", this->iter_);
  hdf5_save_string(file_hid, "learned_net", model_filename);
  hdf5_save_int(file_hid, "current_step", this->current_step_);
  hid_t history_hid = H5Gcreate2(file_hid, "history", H5P_DEFAULT, H5P_DEFAULT,
      H5P_DEFAULT);
  CHECK_GE(history_hid, 0)
      << "Error saving solver state to " << snapshot_filename << ".";
  for (int i = 0; i < history_.size(); ++i) {
    ostringstream oss;
    oss << i;
    hdf5_save_nd_dataset<Dtype>(history_hid, oss.str(), *history_[i]);
  }
  H5Gclose(history_hid);
  H5Fclose(file_hid);
#else
  LOG(FATAL) << "SnapshotSolverStateToHDF5 requires hdf5;"
             << " compile with USE_HDF5.";
#endif  // USE_HDF5
}

PetscErrorCode PetscViewerHDF5OpenGroup(PetscViewer viewer, hid_t *fileId, hid_t *groupId)
{
  hid_t          file_id, group;
  const char     *groupName = NULL;
  PetscErrorCode ierr;

  PetscFunctionBegin;
  ierr = PetscViewerHDF5GetFileId(viewer, &file_id);CHKERRQ(ierr);
  ierr = PetscViewerHDF5GetGroup(viewer, &groupName);CHKERRQ(ierr);
  /* Open group */
  if (groupName) {
    PetscBool root;

    ierr = PetscStrcmp(groupName, "/", &root);CHKERRQ(ierr);
    if (!root && !H5Lexists(file_id, groupName, H5P_DEFAULT)) {
#if (H5_VERS_MAJOR * 10000 + H5_VERS_MINOR * 100 + H5_VERS_RELEASE >= 10800)
      group = H5Gcreate2(file_id, groupName, 0, H5P_DEFAULT, H5P_DEFAULT);
#else /* deprecated HDF5 1.6 API */
      group = H5Gcreate(file_id, groupName, 0);
#endif
      if (group < 0) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_LIB, "Could not create group %s", groupName);
      ierr = H5Gclose(group);CHKERRQ(ierr);
    }
#if (H5_VERS_MAJOR * 10000 + H5_VERS_MINOR * 100 + H5_VERS_RELEASE >= 10800)
    group = H5Gopen2(file_id, groupName, H5P_DEFAULT);
#else
    group = H5Gopen(file_id, groupName);
#endif
    if (group < 0) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_LIB, "Could not open group %s", groupName);
  } else group = file_id;

  *fileId  = file_id;
  *groupId = group;
  PetscFunctionReturn(0);
}

//--------------------------------------------------------------------------
// Function:	CommonFG::createGroup
///\brief	Creates a new group at this location which can be a file
///		or another group.
///\param	name  - IN: Name of the group to create
///\param	size_hint - IN: Indicates the number of bytes to reserve for
///		the names that will appear in the group
///\return	Group instance
///\exception	H5::FileIException or H5::GroupIException
///\par Description
///		The optional \a size_hint specifies how much file space to
///		reserve for storing the names that will appear in this new
///		group. If a non-positive value is provided for the \a size_hint
///		then a default size is chosen.
// Programmer	Binh-Minh Ribler - 2000
//--------------------------------------------------------------------------
Group CommonFG::createGroup( const char* name, size_t size_hint ) const
{
   // Group creation property list for size_hint
   hid_t gcpl_id = 0;

   // Set the local heap size hint
   if(!(size_hint == (size_t)-1 || size_hint == 0)) {

       // If the creation of the property list failed, throw an exception
       if((gcpl_id = H5Pcreate(H5P_GROUP_CREATE)) < 0)
          throwException("createGroup", "H5Pcreate failed");

       if( H5Pset_local_heap_size_hint(gcpl_id, size_hint) < 0) {
          H5Pclose(gcpl_id);
          throwException("createGroup", "H5Pset_local_heap_size failed");
       }
    }

   // Call C routine H5Gcreate2 to create the named group, giving the
   // location id which can be a file id or a group id
   hid_t group_id = H5Gcreate2( getLocId(), name, H5P_DEFAULT, gcpl_id, H5P_DEFAULT );

   // Close the group creation property list, if necessary
   if(gcpl_id > 0)
       H5Pclose(gcpl_id);

   // If the creation of the group failed, throw an exception
   if( group_id < 0 )
      throwException("createGroup", "H5Gcreate2 failed");

   // No failure, create and return the Group object
   Group group( group_id );
   return( group );
}

static void soft_link_example(void)
{
    hid_t file_id;
    hid_t group_id;
    /* Define the link class that we'll use to register "user-defined soft
     * links" using the callbacks we defined above.
     * A link class can have NULL for any callback except its traverse
     * callback.
     */
    const H5L_class_t UD_soft_class[1] = {{
        H5L_LINK_CLASS_T_VERS,      /* Version number for this struct.
                                     * This field is always H5L_LINK_CLASS_T_VERS */
        (H5L_type_t)UD_SOFT_CLASS,  /* Link class id number. This can be any
                                     * value between H5L_TYPE_UD_MIN (64) and
                                     * H5L_TYPE_MAX (255). It should be a
                                     * value that isn't already being used by
                                     * another kind of link. We'll use 65. */
        "UD_soft_link",             /* Link class name for debugging  */
        NULL,                       /* Creation callback              */
        NULL,                       /* Move callback                  */
        NULL,                       /* Copy callback                  */
        UD_soft_traverse,           /* The actual traversal function  */
        NULL,                       /* Deletion callback              */
        NULL                        /* Query callback                 */
    }};


    /* First, create a file and an object within the file for the link to
     * point to.
     */
    file_id = H5Fcreate(SOFT_LINK_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
    group_id = H5Gcreate2(file_id, TARGET_GROUP, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    H5Gclose(group_id);

    /* This is how we create a normal soft link to the group.
     */
    H5Lcreate_soft(TARGET_GROUP, file_id, SOFT_LINK_NAME, H5P_DEFAULT, H5P_DEFAULT);

    /* To do the same thing using a user-defined link, we first have to
     * register the link class we defined.
     */
    H5Lregister(UD_soft_class);

    /* Now create a user-defined link.  We give it the path to the group
     * as its udata.1
     */
    H5Lcreate_ud(file_id, UD_SOFT_LINK_NAME, (H5L_type_t)UD_SOFT_CLASS, TARGET_GROUP,
                 strlen(TARGET_GROUP) + 1, H5P_DEFAULT, H5P_DEFAULT);

    /* We can access the group through the UD soft link like we would through
     * a normal soft link. This link will still dangle if the object's
     * original name is changed or unlinked.
     */
    group_id = H5Gopen2(file_id, UD_SOFT_LINK_NAME, H5P_DEFAULT);

    /* The group is now open normally.  Don't forget to close it! */
    H5Gclose(group_id);

    H5Fclose(file_id);
}

/* Basic external link example
 *
 * Creates two files and uses an external link to access an object in the
 * second file from the first file.
 */
static void extlink_example(void)
{
    hid_t source_file_id, targ_file_id;
    hid_t group_id, group2_id;

    /* Create two files, a source and a target */
    source_file_id = H5Fcreate(SOURCE_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
    targ_file_id = H5Fcreate(TARGET_FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /* Create a group in the target file for the external link to point to. */
    group_id = H5Gcreate2(targ_file_id, "target_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

    /* Close the group and the target file */
    H5Gclose(group_id);

    /* Create an external link in the source file pointing to the target group.
     * We could instead have created the external link first, then created the
     * group it points to; the order doesn't matter.
     */
    H5Lcreate_external(TARGET_FILE, "target_group", source_file_id, "ext_link", H5P_DEFAULT, H5P_DEFAULT);

    /* Now we can use the external link to create a new group inside the
     * target group (even though the target file is closed!).  The external
     * link works just like a soft link.
     */
    group_id = H5Gcreate2(source_file_id, "ext_link/new_group", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

    /* The group is inside the target file and we can access it normally.
     * Here, group_id and group2_id point to the same group inside the
     * target file.
     */
    group2_id = H5Gopen2(targ_file_id, "target_group/new_group", H5P_DEFAULT);

    /* Don't forget to close the IDs we opened. */
    H5Gclose(group2_id);
    H5Gclose(group_id);

    H5Fclose(targ_file_id);
    H5Fclose(source_file_id);

    /* The link from the source file to the target file will work as long as
     * the target file can be found.  If the target file is moved, renamed,
     * or deleted in the filesystem, HDF5 won't be able to find it and the
     * external link will "dangle."
     */
}

/*-------------------------------------------------------------------------
 * Function:	main
 *
 * Purpose:	Runs external dataset tests.
 *
 * Return:	Success:	exit(0)
 *
 *		Failure:	exit(non-zero)
 *
 * Programmer:	Robb Matzke
 *              Tuesday, March  3, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
int
main (void)
{
    hid_t	fapl=-1;		/*file access properties	*/
    hid_t	file=-1;		/*file for test_1* functions	*/
    char	filename[1024];		/*file name for test_1* funcs	*/
    hid_t	grp=-1;			/*group to emit diagnostics	*/
    int		nerrors=0;		/*number of errors		*/

    h5_reset();
    fapl = h5_fileaccess();
    h5_fixname(FILENAME[0], fapl, filename, sizeof filename);
    if((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0) FAIL_STACK_ERROR
    if((grp = H5Gcreate2(file, "emit-diagnostics", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) FAIL_STACK_ERROR
    if(H5Gclose(grp) < 0) goto error;

    nerrors += test_1a(file);
    nerrors += test_1b(file);
    nerrors += test_1c(file);
    nerrors += test_1d(file);
    nerrors += test_1e(file);
    nerrors += test_1f(file);
    nerrors += test_1g();
    nerrors += test_1h();
    nerrors += test_2(fapl);
    nerrors += test_3(fapl);
    nerrors += test_4(fapl);

    /* Verify symbol table messages are cached */
    nerrors += (h5_verify_cached_stabs(FILENAME, fapl) < 0 ? 1 : 0);

    if (nerrors>0) goto error;

    if (H5Fclose(file) < 0) goto error;
    puts("All external storage tests passed.");
    if (h5_cleanup(FILENAME, fapl)) {
        remove("extern_1a.raw");
        remove("extern_1b.raw");
        remove("extern_2a.raw");
        remove("extern_2b.raw");
        remove("extern_3a.raw");
        remove("extern_3b.raw");
        remove("extern_4a.raw");
        remove("extern_4b.raw");
    }

    return 0;

error:
    H5E_BEGIN_TRY {
        H5Fclose(file);
        H5Pclose(fapl);
    } H5E_END_TRY;
    nerrors = MAX(1, nerrors);
    printf ("%d TEST%s FAILED.\n", nerrors, 1==nerrors?"":"s");
    return 1;
}

/**
   Traverse the path of an object in HDF5 file, checking existence of
   groups in the path and creating them if required.  */
hid_t HDF5DataWriter::getDataset(string path)
{
    if (filehandle_ < 0){
        return -1;
    }
    herr_t status = H5Eset_auto2(H5E_DEFAULT, NULL, NULL);
    // Create the groups corresponding to this path
    string::size_type lastslash = path.find_last_of("/");
    vector<string> pathTokens;
    moose::tokenize(path, "/", pathTokens);
    hid_t prev_id = filehandle_;
    hid_t id = -1;
    for ( unsigned int ii = 0; ii < pathTokens.size()-1; ++ii ){
        // check if object exists
        htri_t exists = H5Lexists(prev_id, pathTokens[ii].c_str(),
                                  H5P_DEFAULT);
        if (exists > 0){
            // try to open existing group
            id = H5Gopen2(prev_id, pathTokens[ii].c_str(), H5P_DEFAULT);
        } else if (exists == 0) {
            // If that fails, try to create a group
            id = H5Gcreate2(prev_id, pathTokens[ii].c_str(),
                            H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
        }
        if ((exists < 0) || (id < 0)){
            // Failed to open/create a group, print the
            // offending path (for debugging; the error is
            // perhaps at the level of hdf5 or file system).
            cerr << "Error: failed to open/create group: ";
            for (unsigned int jj = 0; jj <= ii; ++jj){
                cerr << "/" << pathTokens[jj];
            }
            cerr << endl;
            prev_id = -1;
        }
        if (prev_id >= 0  && prev_id != filehandle_){
            // Successfully opened/created new group, close the old group
            status = H5Gclose(prev_id);
            assert( status >= 0 );
        }
        prev_id = id;
    }
    string name = pathTokens[pathTokens.size()-1];
    htri_t exists = H5Lexists(prev_id, name.c_str(), H5P_DEFAULT);
    hid_t dataset_id = -1;
    if (exists > 0){
        dataset_id = H5Dopen2(prev_id, name.c_str(), H5P_DEFAULT);
    } else if (exists == 0){
        dataset_id = createDoubleDataset(prev_id, name);
    } else {
        cerr << "Error: H5Lexists returned "
             << exists << " for path \""
             << path << "\"" << endl;
    }
    return dataset_id;
}

/*-------------------------------------------------------------------------
 * Function: gent_empty_group
 *
 * Purpose: Generate an empty group in a location
 *
 *-------------------------------------------------------------------------
 */
static void gent_empty_group(hid_t loc_id)
{
    hid_t   gid;

    /* Create group in location */
    gid = H5Gcreate2(loc_id, GROUP_EMPTY, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

    /* Release resources */
    H5Gclose(gid);
}

	group(h5a::node const & parent, std::string const & path, bool create) {
		if (!create) {
			open_group(parent, path);
			return;
		}
		h5p::proplist gcpl(H5P_GROUP_CREATE);
		h5e::check_error(H5Pset_link_creation_order(gcpl.hid(),
							    H5P_CRT_ORDER_TRACKED | H5P_CRT_ORDER_INDEXED));
		_self = h5e::check_error(H5Gcreate2(parent.hid(), path.c_str(), H5P_DEFAULT,
						   gcpl.hid(), H5P_DEFAULT));
	}

/*-------------------------------------------------------------------------
 * Function: gent_nested_group
 *
 * Purpose: Generate a group in a location and populate it with another group
 *    containing the "standard" datasets
 *
 *-------------------------------------------------------------------------
 */
static void gent_nested_group(hid_t loc_id)
{
    hid_t   gid;

    /* Create group in location */
    gid = H5Gcreate2(loc_id, GROUP_NESTED, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

    /* Add datasets to group created */
    gent_nested_datasets(gid);

    /* Release resources */
    H5Gclose(gid);
}

int main()
{
	char* filename = "file-test.h5";

	hid_t fprop;
	hid_t vol_id = H5VLregister_by_name("h5-esdm");

	hid_t file_id, group_id, dataset_id, dataspace_id, attribute_id;
	herr_t status;

	char name[1024];

	// SET VOL PLUGIN /////////////////////////////////////////////////////////
	fprop = H5Pcreate(H5P_FILE_ACCESS);
	H5Pset_vol(fprop, vol_id, &fprop);


	// TODO
	// MOCK SETUP /////////////////////////////////////////////////////////////


	/* Create a new file using default properties. */
	file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fprop);

	/* Create a group named "/MyGroup" in the file. */
	group_id = H5Gcreate2(file_id, "/MyGroup", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);

	/* Close the group. */
	status = H5Gclose(group_id);

	/* Terminate access to the file. */
	status = H5Fclose(file_id);

	// MOCK CLEANUP ///////////////////////////////////////////////////////////


	// CREATE /////////////////////////////////////////////////////////////////
	// OPEN ///////////////////////////////////////////////////////////////////
	// CLOSE //////////////////////////////////////////////////////////////////
	// READ ///////////////////////////////////////////////////////////////////
	// WRITE //////////////////////////////////////////////////////////////////
	// GET ////////////////////////////////////////////////////////////////////
	// SPECIFIC ///////////////////////////////////////////////////////////////
	// OPTIONAL ///////////////////////////////////////////////////////////////


	// Clean up ///////////////////////////////////////////////////////////////
	H5VLunregister(vol_id);

	return 0;
}

 int GWriteHDFFile::WriteHeader(gadget_header& header)
 {
           herr_t herr;
           for(int i=0; i<N_TYPE; i++){
               header.npart[i]=npart[i];
           }
           hid_t handle = H5Fopen(filename.c_str(), H5F_ACC_RDWR, H5P_DEFAULT);
           if (handle < 0)
               return -1*handle;
           // Lite interface for making simple attributes
           // H5LTset_attribute_int (file_id, dset_name, attr_name, data, size);
           // herr_t H5LTset_attribute_int( hid_t loc_id, const char *obj_name, const char *attr_name, int *buffer, size_t size)
           hid_t hdgrp = H5Gcreate2(handle, "Header", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
           herr = H5LTset_attribute_uint(handle, "Header", "NumPart_ThisFile", header.npart, N_TYPE);
           if (herr < 0) {
               WARN("Could not write to header");
               return -1*herr;
           }
           herr = H5LTset_attribute_uint(handle, "Header", "NumPart_Total", header.npartTotal, N_TYPE);
           herr = H5LTset_attribute_uint(handle, "Header", "NumPart_Total_HighWord", header.NallHW, N_TYPE);
           herr = H5LTset_attribute_double(handle, "Header", "MassTable", header.mass, N_TYPE);
           if (herr < 0) {
               WARN("Could not write particle numbers");
               return -1*herr;
           }
           herr = H5LTset_attribute_double(handle, "Header", "Time", &header.time, 1);
           herr = H5LTset_attribute_double(handle, "Header", "Redshift", &header.redshift, 1);
           herr = H5LTset_attribute_double(handle, "Header", "BoxSize", &header.BoxSize, 1);
           herr = H5LTset_attribute_int(handle, "Header", "NumFilesPerSnapshot", &header.num_files, 1);
           herr = H5LTset_attribute_double(handle, "Header", "Omega0", &header.Omega0, 1);
           herr = H5LTset_attribute_double(handle, "Header", "OmegaLambda", &header.OmegaLambda, 1);
           herr = H5LTset_attribute_double(handle, "Header", "HubbleParam", &header.HubbleParam, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_Sfr", &header.flag_sfr, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_Cooling", &header.flag_cooling, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_StellarAge", &header.flag_stellarage, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_Metals", &header.flag_metals, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_Feedback", &header.flag_feedback, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_DoublePrecision", &header.flag_doubleprecision, 1);
           herr = H5LTset_attribute_int(handle, "Header", "Flag_IC_Info", &header.flag_ic_info, 1);
           herr = H5LTset_attribute_double(handle, "Header", "UnitLength_in_cm", &header.UnitLength_in_cm, 1);
           herr = H5LTset_attribute_double(handle, "Header", "UnitMass_in_g", &header.UnitMass_in_g, 1);
           herr = H5LTset_attribute_double(handle, "Header", "UnitVelocity_in_cm_per_s", &header.UnitVelocity_in_cm_per_s, 1);
           if (herr < 0) {
               WARN("Could not write final header flags");
               return -1*herr;
           }
           H5Gclose(hdgrp);
           H5Fclose(handle);
           return 0;
 }

/*-------------------------------------------------------------------------
 * Function:	test_misc
 *
 * Purpose:	Test miscellaneous group stuff.
 *
 * Return:	Success:	0
 *
 *		Failure:	number of errors
 *
 * Programmer:	Robb Matzke
 *              Tuesday, November 24, 1998
 *
 *-------------------------------------------------------------------------
 */
static int
test_misc(hid_t fapl, hbool_t new_format)
{
    hid_t	fid = (-1);             /* File ID */
    hid_t	g1 = (-1), g2 = (-1), g3 = (-1);
    char	filename[NAME_BUF_SIZE];
    char	comment[64];

    if(new_format)
        TESTING("miscellaneous group tests (w/new group format)")
    else
        TESTING("miscellaneous group tests")

    /* Create file */
    h5_fixname(FILENAME[0], fapl, filename, sizeof(filename));
    if((fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0) TEST_ERROR

    /* Create initial groups for testing, then close */
    if((g1 = H5Gcreate2(fid, "test_1a", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
    if((g2 = H5Gcreate2(g1, "sub_1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
    if((g3 = H5Gcreate2(fid, "test_1b", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) TEST_ERROR
    if(H5Oset_comment(g3, "hello world") < 0) TEST_ERROR
    if(H5Gclose(g1) < 0) TEST_ERROR
    if(H5Gclose(g2) < 0) TEST_ERROR
    if(H5Gclose(g3) < 0) TEST_ERROR

    /* Open all groups with absolute names to check for exsistence */
    if((g1 = H5Gopen2(fid, "/test_1a", H5P_DEFAULT)) < 0) TEST_ERROR
    if((g2 = H5Gopen2(fid, "/test_1a/sub_1", H5P_DEFAULT)) < 0) TEST_ERROR
    if((g3 = H5Gopen2(fid, "/test_1b", H5P_DEFAULT)) < 0) TEST_ERROR
    if(H5Oget_comment_by_name(g3, "././.", comment, sizeof comment, H5P_DEFAULT) < 0) TEST_ERROR
    if(HDstrcmp(comment, "hello world")) {
	H5_FAILED();
	puts("    Read the wrong comment string from the group.");
	printf("    got: \"%s\"\n    ans: \"hello world\"\n", comment);
	TEST_ERROR
    }