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diff --git a/HDF5Examples/C/H5T/16/h5ex_t_opaqueatt.c b/HDF5Examples/C/H5T/16/h5ex_t_opaqueatt.c
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+++ b/HDF5Examples/C/H5T/16/h5ex_t_opaqueatt.c
@@ -0,0 +1,153 @@
+/************************************************************
+
+  This example shows how to read and write opaque datatypes
+  to an attribute.  The program first writes opaque data to
+  an attribute with a dataspace of DIM0, then closes the
+  file. Next, it reopens the file, reads back the data, and
+  outputs it to the screen.
+
+  This file is intended for use with HDF5 Library version 1.6
+
+ ************************************************************/
+
+#include "hdf5.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+#define FILE      "h5ex_t_opaqueatt.h5"
+#define DATASET   "DS1"
+#define ATTRIBUTE "A1"
+#define DIM0      4
+#define LEN       7
+
+int
+main(void)
+{
+    hid_t   file, space, dtype, dset, attr; /* Handles */
+    herr_t  status;
+    hsize_t dims[1] = {DIM0};
+    size_t  len;
+    char    wdata[DIM0 * LEN], /* Write buffer */
+        *rdata,                /* Read buffer */
+        str[LEN] = "OPAQUE", *tag;
+    int      ndims, i, j;
+    unsigned majnum, minnum, relnum;
+
+    /* Get library version to differentiate between acceptable version methods
+     * to free the tag returned by H5Tget_tag. */
+    H5get_libversion(&majnum, &minnum, &relnum);
+
+    /*
+     * Initialize data.
+     */
+    for (i = 0; i < DIM0; i++) {
+        for (j = 0; j < LEN - 1; j++)
+            wdata[j + i * LEN] = str[j];
+        wdata[LEN - 1 + i * LEN] = (char)i + '0';
+    }
+
+    /*
+     * Create a new file using the default properties.
+     */
+    file = H5Fcreate(FILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    /*
+     * Create dataset with a scalar dataspace.
+     */
+    space  = H5Screate(H5S_SCALAR);
+    dset   = H5Dcreate(file, DATASET, H5T_STD_I32LE, space, H5P_DEFAULT);
+    status = H5Sclose(space);
+
+    /*
+     * Create opaque datatype and set the tag to something appropriate.
+     * For this example we will write and view the data as a character
+     * array.
+     */
+    dtype  = H5Tcreate(H5T_OPAQUE, LEN);
+    status = H5Tset_tag(dtype, "Character array");
+
+    /*
+     * Create dataspace.  Setting maximum size to NULL sets the maximum
+     * size to be the current size.
+     */
+    space = H5Screate_simple(1, dims, NULL);
+
+    /*
+     * Create the attribute and write the opaque data to it.
+     */
+    attr   = H5Acreate(dset, ATTRIBUTE, dtype, space, H5P_DEFAULT);
+    status = H5Awrite(attr, dtype, wdata);
+
+    /*
+     * Close and release resources.
+     */
+    status = H5Aclose(attr);
+    status = H5Dclose(dset);
+    status = H5Sclose(space);
+    status = H5Tclose(dtype);
+    status = H5Fclose(file);
+
+    /*
+     * Now we begin the read section of this example.  Here we assume
+     * the attribute has the same name and rank, but can have any size.
+     * Therefore we must allocate a new array to read in data using
+     * malloc().
+     */
+
+    /*
+     * Open file, dataset, and attribute.
+     */
+    file = H5Fopen(FILE, H5F_ACC_RDONLY, H5P_DEFAULT);
+    dset = H5Dopen(file, DATASET);
+    attr = H5Aopen_name(dset, ATTRIBUTE);
+
+    /*
+     * Get datatype and properties for the datatype.  Note that H5Tget_tag
+     * allocates space for the string in tag, so we must remember to free() it
+     * later.
+     */
+    dtype = H5Aget_type(attr);
+    len   = H5Tget_size(dtype);
+    tag   = H5Tget_tag(dtype);
+
+    /*
+     * Get dataspace and allocate memory for read buffer.
+     */
+    space = H5Aget_space(attr);
+    ndims = H5Sget_simple_extent_dims(space, dims, NULL);
+    rdata = (char *)malloc(dims[0] * len);
+
+    /*
+     * Read the data.
+     */
+    status = H5Aread(attr, dtype, rdata);
+
+    /*
+     * Output the data to the screen.
+     */
+    printf("Datatype tag for %s is: \"%s\"\n", ATTRIBUTE, tag);
+    for (i = 0; i < dims[0]; i++) {
+        printf("%s[%u]: ", ATTRIBUTE, i);
+        for (j = 0; j < len; j++)
+            printf("%c", rdata[j + i * len]);
+        printf("\n");
+    }
+
+    /*
+     * Close and release resources.
+     */
+    free(rdata);
+    /* H5free_memory is available in 1.8.16 and above.
+     * Last version for 1.6 was 1.6.10. */
+    if (minnum > 8 || relnum > 15)
+        H5free_memory(tag);
+    else
+        free(tag);
+    status = H5Aclose(attr);
+    status = H5Dclose(dset);
+    status = H5Sclose(space);
+    status = H5Tclose(dtype);
+    status = H5Fclose(file);
+
+    return 0;
+}