コード例 #1
0
ファイル: h5_vds-percival-unlim.c プロジェクト: Starlink/hdf5
int
main (void)
{
    hid_t        vfile, file, src_space, mem_space, vspace,
                 vdset, dset;                       /* Handles */
    hid_t        dcpl;
    herr_t       status;
    hsize_t      vdsdims[3] = {4*DIM0_1, VDSDIM1, VDSDIM2},
                 vdsdims_max[3] = {VDSDIM0, VDSDIM1, VDSDIM2}, 
                 dims[3] = {DIM0_1, DIM1, DIM2},
                 extdims[3] = {2*DIM0_1, DIM1, DIM2},
                 chunk_dims[3] = {DIM0_1, DIM1, DIM2},
                 dims_max[3] = {DIM0, DIM1, DIM2},
                 vdsdims_out[3],
                 vdsdims_max_out[3],
                 start[3],                   /* Hyperslab parameters */
                 stride[3],
                 count[3],
                 src_count[3],
                 block[3];
    hsize_t      start_out[3],               /* Hyperslab parameter out */
                 stride_out[3],
                 count_out[3],
                 block_out[3];
    int          i, j, k;
    H5D_layout_t layout;                     /* Storage layout */
    size_t       num_map;                    /* Number of mappings */
    ssize_t      len;                        /* Length of the string; also a return value */
    char         *filename;
    char         *dsetname;
    int          wdata[DIM0_1*DIM1*DIM2];
    int          rdata[80][10][10];
    int          a_rdata[20][10][10];

    /*
     * Create source files and datasets. This step is optional.
     */
    for (i=0; i < PLANE_STRIDE; i++) {
        /*
         * Initialize data for i-th source dataset.
         */
        for (j = 0; j < DIM0_1*DIM1*DIM2; j++) wdata[j] = i+1;

        /*
         * Create the source files and  datasets. Write data to each dataset and 
         * close all resources.
         */

        file = H5Fcreate (SRC_FILE[i], H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
        src_space = H5Screate_simple (RANK, dims, dims_max);
        dcpl = H5Pcreate(H5P_DATASET_CREATE);
        status = H5Pset_chunk (dcpl, RANK, chunk_dims);
        dset = H5Dcreate2 (file, SRC_DATASET[i], H5T_NATIVE_INT, src_space, H5P_DEFAULT,
                    dcpl, H5P_DEFAULT);
        status = H5Dwrite (dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT,
                    wdata);
        status = H5Sclose (src_space);
        status = H5Pclose (dcpl);
        status = H5Dclose (dset);
        status = H5Fclose (file);
    }    

    vfile = H5Fcreate (VFILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /* Create VDS dataspace.  */
    vspace = H5Screate_simple (RANK, vdsdims, vdsdims_max);

    /* Create dataspaces for the source dataset. */
    src_space = H5Screate_simple (RANK, dims, dims_max);

    /* Create VDS creation property */
    dcpl = H5Pcreate (H5P_DATASET_CREATE);
     
    /* Initialize hyperslab values */

    start[0] = 0;
    start[1] = 0;
    start[2] = 0;
    stride[0] = PLANE_STRIDE; /* we will select every fifth plane in VDS */
    stride[1] = 1;
    stride[2] = 1;
    count[0] = H5S_UNLIMITED;
    count[1] = 1;
    count[2] = 1;
    src_count[0] = H5S_UNLIMITED;
    src_count[1] = 1;
    src_count[2] = 1;
    block[0] = 1;
    block[1] = DIM1;
    block[2] = DIM2;

    /* 
     * Build the mappings 
     *
     */
    status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, start, NULL, src_count, block);
    for (i=0; i < PLANE_STRIDE; i++) {
        status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
        status = H5Pset_virtual (dcpl, vspace, SRC_FILE[i], SRC_DATASET[i], src_space);
        start[0]++; 
    } 

    H5Sselect_none(vspace); 

    /* Create a virtual dataset */
    vdset = H5Dcreate2 (vfile, DATASET, H5T_NATIVE_INT, vspace, H5P_DEFAULT,
                dcpl, H5P_DEFAULT);
    status = H5Sclose (vspace);
    status = H5Sclose (src_space);
    status = H5Pclose (dcpl);
    /* Let's get space of the VDS and its dimension; we should get 40x10x10 */
    vspace = H5Dget_space (vdset);
    H5Sget_simple_extent_dims (vspace, vdsdims_out, vdsdims_max_out);
    printf ("VDS dimensions first time \n");
    printf (" Current: ");
    for (i=0; i<RANK; i++)
        printf (" %d ", (int)vdsdims_out[i]);
    printf ("\n");

    /* Let's add data to the source datasets and check new dimensions for VDS */

    for (i=0; i < PLANE_STRIDE; i++) {
        /*
         * Initialize data for i-th source dataset.
         */
        for (j = 0; j < DIM0_1*DIM1*DIM2; j++) wdata[j] = 10*(i+1);

        /*
         * Create the source files and  datasets. Write data to each dataset and 
         * close all resources.
         */

        file = H5Fopen (SRC_FILE[i], H5F_ACC_RDWR, H5P_DEFAULT);
        dset = H5Dopen2 (file, SRC_DATASET[i], H5P_DEFAULT);
        status = H5Dset_extent (dset, extdims);       
        src_space = H5Dget_space (dset);
        start[0] = DIM0_1;
        start[1] = 0;
        start[2] = 0;
        count[0] = 1;
        count[1] = 1;
        count[2] = 1;
        block[0] = DIM0_1;
        block[1] = DIM1;
        block[2] = DIM2;

        mem_space = H5Screate_simple(RANK, dims, NULL); 
        status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, start, NULL, count, block);
        status = H5Dwrite (dset, H5T_NATIVE_INT, mem_space, src_space, H5P_DEFAULT,
                    wdata);
        status = H5Sclose (src_space);
        status = H5Dclose (dset);
        status = H5Fclose (file);
      }

    status = H5Dclose (vdset);
    status = H5Fclose (vfile);    
     
    /*
     * Now we begin the read section of this example.
     */

    /*
     * Open file and dataset using the default properties.
     */
    vfile = H5Fopen (VFILE, H5F_ACC_RDONLY, H5P_DEFAULT);
    vdset = H5Dopen2 (vfile, DATASET, H5P_DEFAULT);

    /*
     * Get creation property list and mapping properties.
     */
    dcpl = H5Dget_create_plist (vdset);

    /*
     * Get storage layout.
     */
    layout = H5Pget_layout (dcpl);

    if (H5D_VIRTUAL == layout) 
        printf(" Dataset has a virtual layout \n");
    else
        printf(" Wrong layout found \n");

     /*
      * Find number of mappings.
      */
     status = H5Pget_virtual_count (dcpl, &num_map);
     printf(" Number of mappings is %lu\n", (unsigned long)num_map);

     /* 
      * Get mapping parameters for each mapping.
      */
      for (i = 0; i < (int)num_map; i++) {   
      printf(" Mapping %d \n", i);
      printf("         Selection in the virtual dataset \n");
      /* Get selection in the virttual  dataset */
          vspace = H5Pget_virtual_vspace (dcpl, (size_t)i);
          if (H5Sget_select_type(vspace) == H5S_SEL_HYPERSLABS) { 
              if (H5Sis_regular_hyperslab(vspace)) {
                   status = H5Sget_regular_hyperslab (vspace, start_out, stride_out, count_out, block_out);
                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
               }
          }
      /* Get source file name */
          len = H5Pget_virtual_filename (dcpl, (size_t)i, NULL, 0);
          filename = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_filename (dcpl, (size_t)i, filename, len+1);
          printf("         Source filename %s\n", filename);

      /* Get source dataset name */
          len = H5Pget_virtual_dsetname (dcpl, (size_t)i, NULL, 0);
          dsetname = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_dsetname (dcpl, (size_t)i, dsetname, len+1);
          printf("         Source dataset name %s\n", dsetname);

      /* Get selection in the source dataset */
          printf("         Selection in the source dataset \n");
          src_space = H5Pget_virtual_srcspace (dcpl, (size_t)i);
          if (H5Sget_select_type(src_space) == H5S_SEL_HYPERSLABS) {
              if (H5Sis_regular_hyperslab(src_space)) {
                   status = H5Sget_regular_hyperslab (src_space, start_out, stride_out, count_out, block_out);
                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
               }
          }
          H5Sclose(vspace);
          H5Sclose(src_space);
          free(filename);
          free(dsetname);
      }
    /*
     * Read data from VDS.
     */
    vspace = H5Dget_space (vdset);
    H5Sget_simple_extent_dims (vspace, vdsdims_out, vdsdims_max_out);
    printf ("VDS dimensions second time \n");
    printf (" Current: ");
    for (i=0; i<RANK; i++)
        printf (" %d ", (int)vdsdims_out[i]);
    printf ("\n");

    /* Read all VDS data */

    /* EIP We should be able to do it by using H5S_ALL instead of making selection
     * or using H5Sselect_all from vspace. 
     */
    start[0] = 0;
    start[1] = 0;
    start[2] = 0;
    count[0] = 1;
    count[1] = 1;
    count[2] = 1;
    block[0] = vdsdims_out[0];
    block[1] = vdsdims_out[1];
    block[2] = vdsdims_out[2];

    status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, NULL, count, block);
    mem_space = H5Screate_simple(RANK, vdsdims_out, NULL);
    status = H5Dread (vdset, H5T_NATIVE_INT, mem_space, vspace, H5P_DEFAULT,
                    rdata);   
    printf (" All data: \n");
    for (i=0; i < (int)vdsdims_out[0]; i++) {
        for (j=0; j < (int)vdsdims_out[1]; j++) {
             printf ("(%d, %d, 0)", i, j);
             for (k=0; k < (int)vdsdims_out[2]; k++) 
                 printf (" %d ", rdata[i][j][k]);
             printf ("\n");
        }
    }
    /* Read VDS, but only data mapeed to dataset a.h5 */
    start[0] = 0;
    start[1] = 0;
    start[2] = 0;
    stride[0] = PLANE_STRIDE;
    stride[1] = 1;
    stride[2] = 1;
    count[0] = 2*DIM0_1;
    count[1] = 1;
    count[2] = 1;
    block[0] = 1;
    block[1] = vdsdims_out[1];
    block[2] = vdsdims_out[2];
    dims[0] = 2*DIM0_1; 
    status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
    mem_space = H5Screate_simple(RANK, dims,  NULL);
    status = H5Dread (vdset, H5T_NATIVE_INT, mem_space, vspace, H5P_DEFAULT,
                    a_rdata);   
    printf (" All data: \n");
    for (i=0; i < 2*DIM0_1; i++) {
        for (j=0; j < (int)vdsdims_out[1]; j++) {
             printf ("(%d, %d, 0)", i, j);
             for (k=0; k < (int)vdsdims_out[2]; k++) 
                 printf (" %d ", a_rdata[i][j][k]);
             printf ("\n");
        }
    }
    /*
     * Close and release resources.
     */
    status = H5Sclose(mem_space);
    status = H5Pclose (dcpl);
    status = H5Dclose (vdset);
    status = H5Fclose (vfile);
    return 0;
}
コード例 #2
0
int
main (void)
{
    hid_t        vfile, file, src_space, mem_space, vspace,
                 vdset, dset;                       /* Handles */
    hid_t        dcpl, dapl;
    herr_t       status;
    hsize_t      vdsdims[3] = {4*DIM0_1, VDSDIM1, VDSDIM2},
                 vdsdims_max[3] = {VDSDIM0, VDSDIM1, VDSDIM2}, 
                 dims[3] = {DIM0_1, DIM1, DIM2},
                 memdims[3] = {DIM0_1, DIM1, DIM2},
                 extdims[3] = {0, DIM1, DIM2}, /* Dimensions of the extended source datasets */
                 chunk_dims[3] = {DIM0_1, DIM1, DIM2},
                 dims_max[3] = {DIM0, DIM1, DIM2},
                 vdsdims_out[3],
                 vdsdims_max_out[3],
                 start[3],                   /* Hyperslab parameters */
                 stride[3],
                 count[3],
                 src_count[3],
                 block[3];
    hsize_t      start_out[3],               /* Hyperslab parameter out */
                 stride_out[3],
                 count_out[3],
                 block_out[3];
    int          i, j;
    H5D_layout_t layout;                     /* Storage layout */
    size_t       num_map;                    /* Number of mappings */
    ssize_t      len;                        /* Length of the string; also a return value */
    char         *filename;
    char         *dsetname;
    int          wdata[DIM0_1*DIM1*DIM2];

    /*
     * Create source files and datasets. This step is optional.
     */
    for (i=0; i < PLANE_STRIDE; i++) {
        /*
         * Initialize data for i-th source dataset.
         */
        for (j = 0; j < DIM0_1*DIM1*DIM2; j++) wdata[j] = i+1;

        /*
         * Create the source files and  datasets. Write data to each dataset and 
         * close all resources.
         */

        file = H5Fcreate (SRC_FILE[i], H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
        src_space = H5Screate_simple (RANK, dims, dims_max);
        dcpl = H5Pcreate(H5P_DATASET_CREATE);
        status = H5Pset_chunk (dcpl, RANK, chunk_dims);
        dset = H5Dcreate2 (file, SRC_DATASET[i], H5T_NATIVE_INT, src_space, H5P_DEFAULT,
                    dcpl, H5P_DEFAULT);
        status = H5Dwrite (dset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT,
                    wdata);
        status = H5Sclose (src_space);
        status = H5Pclose (dcpl);
        status = H5Dclose (dset);
        status = H5Fclose (file);
    }    

    vfile = H5Fcreate (VFILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /* Create VDS dataspace.  */
    vspace = H5Screate_simple (RANK, vdsdims, vdsdims_max);

    /* Create dataspaces for the source dataset. */
    src_space = H5Screate_simple (RANK, dims, dims_max);

    /* Create VDS creation property */
    dcpl = H5Pcreate (H5P_DATASET_CREATE);
     
    /* Initialize hyperslab values */

    start[0] = 0;
    start[1] = 0;
    start[2] = 0;
    stride[0] = PLANE_STRIDE; /* we will select every fifth plane in VDS */
    stride[1] = 1;
    stride[2] = 1;
    count[0] = H5S_UNLIMITED;
    count[1] = 1;
    count[2] = 1;
    src_count[0] = H5S_UNLIMITED;
    src_count[1] = 1;
    src_count[2] = 1;
    block[0] = 1;
    block[1] = DIM1;
    block[2] = DIM2;

    /* 
     * Build the mappings 
     *
     */
    status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, start, NULL, src_count, block);
    for (i=0; i < PLANE_STRIDE; i++) {
        status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
        status = H5Pset_virtual (dcpl, vspace, SRC_FILE[i], SRC_DATASET[i], src_space);
        start[0]++; 
    } 

    H5Sselect_none(vspace); 

    /* Create a virtual dataset */
    vdset = H5Dcreate2 (vfile, DATASET, H5T_NATIVE_INT, vspace, H5P_DEFAULT,
                dcpl, H5P_DEFAULT);
    status = H5Sclose (vspace);
    status = H5Sclose (src_space);
    status = H5Pclose (dcpl);

    /* Let's add data to the source datasets and check new dimensions for VDS */
    /* We will add only one plane to the first source dataset, two planes to the
       second one, three to the third, and four to the forth.                 */

    for (i=0; i < PLANE_STRIDE; i++) {
        /*
         * Initialize data for i-th source dataset.
         */
        for (j = 0; j < (i+1)*DIM1*DIM2; j++) wdata[j] = 10*(i+1);

        /*
         * Open the source files and datasets. Appen data to each dataset and 
         * close all resources.
         */

        file = H5Fopen (SRC_FILE[i], H5F_ACC_RDWR, H5P_DEFAULT);
        dset = H5Dopen2 (file, SRC_DATASET[i], H5P_DEFAULT);
        extdims[0] = DIM0_1+i+1;
        status = H5Dset_extent (dset, extdims);       
        src_space = H5Dget_space (dset);
        start[0] = DIM0_1;
        start[1] = 0;
        start[2] = 0;
        count[0] = 1;
        count[1] = 1;
        count[2] = 1;
        block[0] = i+1;
        block[1] = DIM1;
        block[2] = DIM2;

        memdims[0] = i+1;
        mem_space = H5Screate_simple(RANK, memdims, NULL); 
        status = H5Sselect_hyperslab (src_space, H5S_SELECT_SET, start, NULL, count, block);
        status = H5Dwrite (dset, H5T_NATIVE_INT, mem_space, src_space, H5P_DEFAULT,
                    wdata);
        status = H5Sclose (src_space);
        status = H5Dclose (dset);
        status = H5Fclose (file);
      }

    status = H5Dclose (vdset);
    status = H5Fclose (vfile);    
     
    /*
     * Now we begin the read section of this example.
     */

    /*
     * Open file and dataset using the default properties.
     */
    vfile = H5Fopen (VFILE, H5F_ACC_RDONLY, H5P_DEFAULT);
    
    /* 
     * Open VDS using different access properties to use max or
     * min extents depending on the sizes of the underlying datasets
     */
    dapl = H5Pcreate (H5P_DATASET_ACCESS);

    for(i = 0; i < 2; i++) {
        status = H5Pset_virtual_view (dapl, i ? H5D_VDS_LAST_AVAILABLE : H5D_VDS_FIRST_MISSING);
        vdset = H5Dopen2 (vfile, DATASET, dapl);

        /* Let's get space of the VDS and its dimension; we should get 32(or 20)x10x10 */
        vspace = H5Dget_space (vdset);
        H5Sget_simple_extent_dims (vspace, vdsdims_out, vdsdims_max_out);
        printf ("VDS dimensions, bounds = H5D_VDS_%s: ", i ? "LAST_AVAILABLE" : "FIRST_MISSING");
        for (j=0; j<RANK; j++)
            printf (" %d ", (int)vdsdims_out[j]);
        printf ("\n");

        /* Close */
        status = H5Dclose (vdset);
        status = H5Sclose (vspace);
    }

    status = H5Pclose (dapl);

    vdset = H5Dopen2 (vfile, DATASET, H5P_DEFAULT);

    /*
     * Get creation property list and mapping properties.
     */
    dcpl = H5Dget_create_plist (vdset);

    /*
     * Get storage layout.
     */
    layout = H5Pget_layout (dcpl);

    if (H5D_VIRTUAL == layout) 
        printf(" Dataset has a virtual layout \n");
    else
        printf(" Wrong layout found \n");

     /*
      * Find number of mappings.
      */
     status = H5Pget_virtual_count (dcpl, &num_map);
     printf(" Number of mappings is %lu\n", (unsigned long)num_map);

     /* 
      * Get mapping parameters for each mapping.
      */
      for (i = 0; i < (int)num_map; i++) {   
      printf(" Mapping %d \n", i);
      printf("         Selection in the virtual dataset \n");
      /* Get selection in the virttual  dataset */
          vspace = H5Pget_virtual_vspace (dcpl, (size_t)i);
          if (H5Sget_select_type(vspace) == H5S_SEL_HYPERSLABS) { 
              if (H5Sis_regular_hyperslab(vspace)) {
                   status = H5Sget_regular_hyperslab (vspace, start_out, stride_out, count_out, block_out);
                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
               }
          }
      /* Get source file name */
          len = H5Pget_virtual_filename (dcpl, (size_t)i, NULL, 0);
          filename = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_filename (dcpl, (size_t)i, filename, len+1);
          printf("         Source filename %s\n", filename);

      /* Get source dataset name */
          len = H5Pget_virtual_dsetname (dcpl, (size_t)i, NULL, 0);
          dsetname = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_dsetname (dcpl, (size_t)i, dsetname, len+1);
          printf("         Source dataset name %s\n", dsetname);

      /* Get selection in the source dataset */
          printf("         Selection in the source dataset \n");
          src_space = H5Pget_virtual_srcspace (dcpl, (size_t)i);
          if (H5Sget_select_type(src_space) == H5S_SEL_HYPERSLABS) {
              if (H5Sis_regular_hyperslab(src_space)) {
                   status = H5Sget_regular_hyperslab (src_space, start_out, stride_out, count_out, block_out);
                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
               }
          }
          H5Sclose(vspace);
          H5Sclose(src_space);
          free(filename);
          free(dsetname);
      }
    /*
     * Close and release resources.
     */
    status = H5Pclose (dcpl);
    status = H5Dclose (vdset);
    status = H5Fclose (vfile);
    return 0;
}
コード例 #3
0
ファイル: h5_vds-eiger.c プロジェクト: ElaraFX/hdf5
int
main (void)
{
    hid_t        file, src_space, vspace,
                 dset;                       /* Handles */
    hid_t        dcpl;
    herr_t       status;
    hsize_t      vdsdims[3] = {VDSDIM0, VDSDIM1, VDSDIM2},
                 vdsdims_max[3] = {H5S_UNLIMITED, VDSDIM1, VDSDIM1},
                 dims[3] = {DIM0, DIM1, DIM2},
                 start[3],                   /* Hyperslab parameters */
                 stride[3],
                 count[3],
                 block[3];
    hsize_t      start_out[3],               /* Hyperslab parameter out */
                 stride_out[3],
                 count_out[3],
                 block_out[3];
    int          i;
    H5D_layout_t layout;                     /* Storage layout */
    size_t       num_map;                    /* Number of mappings */
    ssize_t      len;                        /* Length of the string; also a return value */
    char         *filename;
    char         *dsetname;


    file = H5Fcreate (FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);

    /* Create VDS dataspace.  */
    vspace = H5Screate_simple (RANK, vdsdims, vdsdims_max);

    /* Create dataspaces for the source dataset. */
    src_space = H5Screate_simple (RANK, dims, NULL);

    /* Create VDS creation property */
    dcpl = H5Pcreate (H5P_DATASET_CREATE);
     
    /* Initialize hyperslab values */

    start[0] = 0;
    start[1] = 0;
    start[2] = 0;
    stride[0] = DIM0;
    stride[1] = 1;
    stride[2] = 1;
    count[0] = H5S_UNLIMITED;
    count[1] = 1;
    count[2] = 1;
    block[0] = DIM0;
    block[1] = DIM1;
    block[2] = DIM2;

   /* 
    * Build the mappings 
    *
    */
      status = H5Sselect_hyperslab (vspace, H5S_SELECT_SET, start, stride, count, block);
      status = H5Pset_virtual (dcpl, vspace, "f-%b.h5", "/A", src_space);
   


   /* Create a virtual dataset */
      dset = H5Dcreate2 (file, DATASET, H5T_NATIVE_INT, vspace, H5P_DEFAULT,
                  dcpl, H5P_DEFAULT);
      status = H5Sclose (vspace);
      status = H5Sclose (src_space);
      status = H5Dclose (dset);
      status = H5Fclose (file);    
     

    /*
     * Now we begin the read section of this example.
     */

    /*
     * Open file and dataset using the default properties.
     */
    file = H5Fopen (FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
    dset = H5Dopen2 (file, DATASET, H5P_DEFAULT);

    /*
     * Get creation property list and mapping properties.
     */
    dcpl = H5Dget_create_plist (dset);

    /*
     * Get storage layout.
     */
    layout = H5Pget_layout (dcpl);

    if (H5D_VIRTUAL == layout) 
        printf(" Dataset has a virtual layout \n");
    else
        printf(" Wrong layout found \n");

     /*
      * Find number of mappings.
      */
     status = H5Pget_virtual_count (dcpl, &num_map);
     printf(" Number of mappings is %d\n", (int)num_map);

     /* 
      * Get mapping parameters for each mapping.
      */
      for (i = 0; i < (int)num_map; i++) {   
      printf(" Mapping %d \n", i);
      printf("         Selection in the virtual dataset \n");
      /* Get selection in the virttual  dataset */
          vspace = H5Pget_virtual_vspace (dcpl, (size_t)i);
          if (H5Sget_select_type(vspace) == H5S_SEL_HYPERSLABS) { 
              if (H5Sis_regular_hyperslab(vspace)) {
                   status = H5Sget_regular_hyperslab (vspace, start_out, stride_out, count_out, block_out);
                   printf("         start  = [%llu, %llu, %llu] \n", (unsigned long long)start_out[0], (unsigned long long)start_out[1], (unsigned long long)start_out[2]);
                   printf("         stride = [%llu, %llu, %llu] \n", (unsigned long long)stride_out[0], (unsigned long long)stride_out[1], (unsigned long long)stride_out[2]);
                   printf("         count  = [%llu, %llu, %llu] \n", (unsigned long long)count_out[0], (unsigned long long)count_out[1], (unsigned long long)count_out[2]);
                   printf("         block  = [%llu, %llu, %llu] \n", (unsigned long long)block_out[0], (unsigned long long)block_out[1], (unsigned long long)block_out[2]);
               }
          }
      /* Get source file name */
          len = H5Pget_virtual_filename (dcpl, (size_t)i, NULL, 0);
          filename = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_filename (dcpl, (size_t)i, filename, len+1);
          printf("         Source filename %s\n", filename);

      /* Get source dataset name */
          len = H5Pget_virtual_dsetname (dcpl, (size_t)i, NULL, 0);
          dsetname = (char *)malloc((size_t)len*sizeof(char)+1);
          H5Pget_virtual_dsetname (dcpl, (size_t)i, dsetname, len+1);
          printf("         Source dataset name %s\n", dsetname);

      /* Get selection in the source dataset */
          printf("         Selection in the source dataset ");
          src_space = H5Pget_virtual_srcspace (dcpl, (size_t)i);
          if(H5Sget_select_type(src_space) == H5S_SEL_ALL) {
                  printf("H5S_ALL \n");
          }
/* EIP read data back */
          H5Sclose(vspace);
          H5Sclose(src_space);
          free(filename);
          free(dsetname);
      }

    /*
     * Close and release resources.
     */
    status = H5Pclose (dcpl);
    status = H5Dclose (dset);
    status = H5Fclose (file);

    return 0;
}