Merging in latest from upstream (HDFFV/hdf5:refs/heads/develop)

* commit 'af21ce90d9465e805807f17da21f93e64e03492a': (46 commits)
  Changed to Unix line endings and chmod -x.
  Fix runtest case for data to stdout in tool
  Updated the parallel install docs.
  Eliminated the need for a separate script variable.
  Flipped swapped testing strings.
  Specify variable type. Remove unnecessary whitespace.
  Added test_vol_plugin.sh to the list of scripts to clean
  Fixed a CMake build issue (CMake still doesn't run the VOL plugin tests)
  Added more sub-tests to the VOL plugin test.
  Added a simple test for registration of VOL connector plugins. Autotools only for right now, but this will be fleshed out in future work.
  OHDR tests now accept h5_fileaccess() fapls. Formatting, informative comments, and minor renaming.
  Fix some CMake listings
  Add error checking to the minimized dset header size calculation. Update printf->HDprintf statements.
  Remove `#if 0` block of deprecated code.
  Fix mistake with H5E_BEGIN_TRY {...} H5E_END_TRY block containing ERROR-raising macros. Formatting tweaks.
  Added a helpful message to the flush script.
  Added a shell script so we can run the parallel flush test on OpenMPI.
  Add "compact" storage test to relative header size comparisons.
  Formatting adjustments.
  Formatting adjustments
  ...

24 files changed, 779 insertions, 156 deletions

diff --git a/src/H5Dint.c b/src/H5Dint.c
index 6bb3343..7eb1aaf 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -25,6 +25,7 @@
 #include "H5CXprivate.h"        /* API Contexts                             */
 #include "H5Dpkg.h"             /* Datasets                                 */
 #include "H5Eprivate.h"         /* Error handling                           */
+#include "H5Fprivate.h"         /* Files                                    */
 #include "H5FLprivate.h"        /* Free Lists                               */
 #include "H5FOprivate.h"        /* File objects                             */
 #include "H5Iprivate.h"         /* IDs                                      */
@@ -59,6 +60,9 @@ static herr_t H5D__init_storage(const H5D_io_info_t *io_info, hbool_t full_overw
         hsize_t old_dim[]);
 static herr_t H5D__append_flush_setup(H5D_t *dset, hid_t dapl_id);
 static herr_t H5D__close_cb(H5VL_object_t *dset_vol_obj);
+static herr_t H5D__use_minimized_dset_headers(H5F_t *file, H5D_t *dset, hbool_t *minimize);
+static herr_t H5D__prepare_minimized_oh(H5F_t *file, H5D_t *dset, H5O_loc_t *oloc);
+static size_t H5D__calculate_minimum_header_size(H5F_t *file, H5D_t *dset, H5O_t *ohdr);
 
 
 /*********************/
@@ -658,6 +662,211 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:   H5D__use_minimized_dset_headers
+ *
+ * Purpose:    Compartmentalize check for file- or dcpl-set values indicating
+ *             to create a "minimized" dataset object header.
+ *             Upon success, write resulting value to out pointer `minimize`.
+ *
+ * Return:     Success: SUCCEED (0) (non-negative value)
+ *             Failure: FAIL (-1) (negative value)
+ *
+ * Programmer: Jacob Smith
+ *             16 August 2018
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D__use_minimized_dset_headers(H5F_t *file, H5D_t *dset, hbool_t *minimize)
+{
+    H5P_genplist_t *plist     = NULL;
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT;
+
+    HDassert(file);
+    HDassert(dset);
+    HDassert(minimize);
+
+    plist = H5P_object_verify(dset->shared->dcpl_id, H5P_DATASET_CREATE);
+    if(NULL == plist)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "problem getting dcpl")
+    if(H5P_get(plist, H5D_CRT_MIN_DSET_HDR_SIZE_NAME, minimize) == FAIL)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get minimize value from dcpl")
+
+    if(FALSE == *minimize)
+        *minimize = H5F_get_min_dset_ohdr(file);
+
+done:
+    if(FAIL == ret_value)
+        *minimize = FALSE;
+    FUNC_LEAVE_NOAPI(ret_value);
+} /* H5D__use_minimized_dset_headers */
+
+
+/*-------------------------------------------------------------------------
+ * Function:   H5D__calculate_minimium_header_size
+ *
+ * Purpose:    Calculate the size required for the minimized object header.
+ *
+ * Return:     Success: Positive value > 0
+ *             Failure: 0
+ *
+ * Programmer: Jacob Smith
+ *             16 August 2018
+ *-------------------------------------------------------------------------
+ */
+static size_t
+H5D__calculate_minimum_header_size(H5F_t *file, H5D_t *dset, H5O_t *ohdr)
+{
+    H5T_t      *type             = NULL;
+    H5O_fill_t *fill_prop        = NULL;
+    hbool_t     use_at_least_v18 = FALSE;
+    const char  continuation[1]  = ""; /* requred for work-around */
+    size_t      get_value        = 0;
+    size_t      ret_value        = 0;
+
+    FUNC_ENTER_NOAPI_NOINIT;
+
+    HDassert(file);
+    HDassert(dset);
+    HDassert(ohdr);
+
+    type = dset->shared->type;
+    fill_prop = &(dset->shared->dcpl_cache.fill);
+    use_at_least_v18 = (H5F_LOW_BOUND(file) >= H5F_LIBVER_V18);
+
+    /* Datatype message size */
+    get_value = H5O_msg_size_oh(file, ohdr, H5O_DTYPE_ID, type, 0);
+    if (get_value == 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "Can't get size of datatype message")
+    ret_value += get_value;
+
+    /* Shared Dataspace message size */
+    get_value = H5O_msg_size_oh(file, ohdr, H5O_SDSPACE_ID, dset->shared->space, 0);
+    if (get_value == 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of dataspace message")
+    ret_value += get_value;
+
+    /* "Layout" message size */
+    get_value = H5O_msg_size_oh(file, ohdr, H5O_LAYOUT_ID, &dset->shared->layout, 0);
+    if (get_value == 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of layout message")
+    ret_value += get_value;
+
+    /* Fill Value message size */
+    get_value = H5O_msg_size_oh(file, ohdr, H5O_FILL_NEW_ID, fill_prop, 0);
+    if (get_value == 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of fill value message")
+    ret_value += get_value;
+
+    /* "Continuation" message size */
+    /* message pointer "continuation" is unused by raw get function, however,
+     * a null pointer would be intercepted by an assert in H5O_msg_size_oh().
+     */
+    get_value = H5O_msg_size_oh(file, ohdr, H5O_CONT_ID, continuation, 0);
+    if (get_value == 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of continuation message")
+    ret_value += get_value;
+
+    /* Fill Value (backwards compatability) message size */
+    if(fill_prop->buf && !use_at_least_v18) {
+        H5O_fill_t old_fill_prop; /* Copy for writing "old" fill value */
+
+        /* Shallow copy the fill value property */
+        /* guards against shared component modification */
+        HDmemcpy(&old_fill_prop, fill_prop, sizeof(old_fill_prop));
+
+        if (H5O_msg_reset_share(H5O_FILL_ID, &old_fill_prop) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't reset the copied fill property")
+
+        get_value = H5O_msg_size_oh(file, ohdr, H5O_FILL_ID, &old_fill_prop, 0);
+        if (get_value == 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of fill value (backwards compat) message")
+        ret_value += get_value;
+    }
+
+    /* Filter/Pipeline message size */
+    if(H5D_CHUNKED == dset->shared->layout.type) {
+        H5O_pline_t *pline = &dset->shared->dcpl_cache.pline;
+        if(pline->nused > 0) {
+            get_value = H5O_msg_size_oh(file, ohdr, H5O_PLINE_ID, pline, 0);
+            if (get_value == 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of filter message")
+            ret_value += get_value;
+        }
+    }
+
+    /* External File Link message size */
+    if(dset->shared->dcpl_cache.efl.nused > 0) {
+        get_value = H5O_msg_size_oh(file, ohdr, H5O_EFL_ID, &dset->shared->dcpl_cache.efl, 0);
+        if (get_value == 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of external file link message")
+        ret_value += get_value;
+    }
+
+    /* Modification Time message size */
+    if(H5O_HDR_STORE_TIMES & H5O_OH_GET_FLAGS(ohdr)) {
+        HDassert(H5O_OH_GET_VERSION(ohdr) >= 1); /* 1 :: H5O_VERSION_1 (H5Opkg.h) */
+
+        if(H5O_OH_GET_VERSION(ohdr) == 1) {
+            /* v1 object headers store modification time as a message */
+            time_t mtime;
+            get_value = H5O_msg_size_oh(file, ohdr, H5O_MTIME_NEW_ID, &mtime, 0);
+            if (get_value == 0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, 0, "can't get size of modification time message")
+            ret_value += get_value;
+        }
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value);
+} /* H5D__calculate_minimum_header_size */
+
+
+/*-------------------------------------------------------------------------
+ * Function:   H5D__prepare_minimized_oh
+ *
+ * Purpose:    Create an object header (H5O_t) allocated with the smallest
+ *             possible size.
+ *
+ * Return:     Success: SUCCEED (0) (non-negative value)
+ *             Failure: FAIL (-1) (negative value)
+ *
+ * Programmer: Jacob Smith
+ *             16 August 2018
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5D__prepare_minimized_oh(H5F_t *file, H5D_t *dset, H5O_loc_t *oloc)
+{
+    H5O_t  *oh        = NULL;
+    size_t  ohdr_size = 0;
+    herr_t  ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT;
+
+    HDassert(file);
+    HDassert(dset);
+    HDassert(oloc);
+
+    oh = H5O__create_ohdr(file, dset->shared->dcpl_id);
+    if(NULL == oh)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "can't instantiate object header")
+
+    ohdr_size = H5D__calculate_minimum_header_size(file, dset, oh);
+    if (ohdr_size == 0)
+       HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "computed header size is invalid")
+
+    /* Special allocation of space for compact datsets is handled by the call here. */
+    if(H5O__apply_ohdr(file, oh, dset->shared->dcpl_id, ohdr_size, (size_t)1, oloc) == FAIL)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "can't apply object header to file")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value);
+} /* H5D__prepare_minimized_oh */
+
+
+/*-------------------------------------------------------------------------
  * Function: H5D__update_oh_info
  *
  * Purpose:  Create and fill object header for dataset
@@ -669,17 +878,18 @@ done:
 static herr_t
 H5D__update_oh_info(H5F_t *file, H5D_t *dset, hid_t dapl_id)
 {
-    H5O_t              *oh = NULL;      /* Pointer to dataset's object header */
-    size_t              ohdr_size = H5D_MINHDR_SIZE;    /* Size of dataset's object header */
-    H5O_loc_t          *oloc = NULL;    /* Dataset's object location */
-    H5O_layout_t       *layout;         /* Dataset's layout information */
-    H5T_t              *type;           /* Dataset's datatype */
-    H5O_fill_t         *fill_prop;      /* Pointer to dataset's fill value information */
-    H5D_fill_value_t    fill_status;    /* Fill value status */
-    hbool_t             fill_changed = FALSE;   /* Flag indicating the fill value was changed */
-    hbool_t             layout_init = FALSE;    /* Flag to indicate that chunk information was initialized */
-    hbool_t             use_at_least_v18;       /* Flag indicating to use at least v18 format versions */
-    herr_t ret_value = SUCCEED;         /* Return value */
+    H5O_t            *oh = NULL;      /* Pointer to dataset's object header */
+    size_t            ohdr_size = H5D_MINHDR_SIZE;    /* Size of dataset's object header */
+    H5O_loc_t        *oloc = NULL;    /* Dataset's object location */
+    H5O_layout_t     *layout;         /* Dataset's layout information */
+    H5T_t            *type;           /* Dataset's datatype */
+    H5O_fill_t       *fill_prop;      /* Pointer to dataset's fill value information */
+    H5D_fill_value_t  fill_status;    /* Fill value status */
+    hbool_t           fill_changed = FALSE;   /* Flag indicating the fill value was changed */
+    hbool_t           layout_init = FALSE;    /* Flag to indicate that chunk information was initialized */
+    hbool_t           use_at_least_v18;       /* Flag indicating to use at least v18 format versions */
+    hbool_t           minimize_header = FALSE;
+    herr_t            ret_value = SUCCEED;         /* Return value */
 
     FUNC_ENTER_STATIC
 
@@ -747,13 +957,24 @@ H5D__update_oh_info(H5F_t *file, H5D_t *dset, hid_t dapl_id)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set fill value info")
     } /* end if */
 
-    /* Add the dataset's raw data size to the size of the header, if the raw data will be stored as compact */
-    if(layout->type == H5D_COMPACT)
-        ohdr_size += layout->storage.u.compact.size;
+    if(H5D__use_minimized_dset_headers(file, dset, &minimize_header) == FAIL)
+        HGOTO_ERROR(H5E_ARGS, H5E_CANTGET, FAIL, "can't get minimize settings")
+
+    if(TRUE == minimize_header) {
+        if(H5D__prepare_minimized_oh(file, dset, oloc) == FAIL)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't create minimized dataset object header")
+    } else {
+        /* Add the dataset's raw data size to the size of the header, if the
+         * raw data will be stored as compact
+         */
+        if(H5D_COMPACT == layout->type)
+            ohdr_size += layout->storage.u.compact.size;
+
+        /* Create an object header for the dataset */
+        if(H5O_create(file, ohdr_size, (size_t)1, dset->shared->dcpl_id, oloc/*out*/) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to create dataset object header")
+    } /* If use minimum/standard object header space */
 
-    /* Create an object header for the dataset */
-    if(H5O_create(file, ohdr_size, (size_t)1, dset->shared->dcpl_id, oloc/*out*/) < 0)
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to create dataset object header")
     HDassert(file == dset->oloc.file);
 
     /* Pin the object header */
@@ -910,7 +1131,7 @@ H5D__build_file_prefix(const H5D_t *dset, hid_t dapl_id, const char *prefix_type
             HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
     } /* end if */
     else {
-        if (HDstrncmp(prefix, "${ORIGIN}", HDstrlen("${ORIGIN}")) == 0) {
+        if(HDstrncmp(prefix, "${ORIGIN}", HDstrlen("${ORIGIN}")) == 0) {
             /* Replace ${ORIGIN} at beginning of prefix by directory of HDF5 file */
             filepath_len = HDstrlen(filepath);
             prefix_len = HDstrlen(prefix);
diff --git a/src/H5Dprivate.h b/src/H5Dprivate.h
index 4e9cda8..aaa3db2 100644
--- a/src/H5Dprivate.h
+++ b/src/H5Dprivate.h
@@ -45,6 +45,7 @@
 #define H5D_CRT_FILL_VALUE_NAME    "fill_value"          /* Fill value */
 #define H5D_CRT_ALLOC_TIME_STATE_NAME "alloc_time_state" /* Space allocation time state */
 #define H5D_CRT_EXT_FILE_LIST_NAME "efl"                 /* External file list */
+#define H5D_CRT_MIN_DSET_HDR_SIZE_NAME "dset_oh_minimize"/* Minimize object header */
 
 /* ========  Dataset access property names ======== */
 #define H5D_ACS_DATA_CACHE_NUM_SLOTS_NAME   "rdcc_nslots"    /* Size of raw data chunk cache(slots) */
diff --git a/src/H5F.c b/src/H5F.c
index b17d94f..0ff3f1f 100644
--- a/src/H5F.c
+++ b/src/H5F.c
@@ -1335,7 +1335,7 @@ H5Fget_metadata_read_retry_info(hid_t file_id, H5F_retry_info_t *info)
     H5TRACE2("e", "i*x", file_id, info);
 
     /* Check args */
-    if (!info)
+    if(!info)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no info struct")
 
     /* Get the file pointer */
@@ -1822,3 +1822,89 @@ done:
     FUNC_LEAVE_API(ret_value)
 } /* H5Fincrement_filesize() */
 
+
+/*-------------------------------------------------------------------------
+ * Function: H5Fget_dset_no_attrs_hint
+ *
+ * Purpose:
+ *
+ *     Get the file-level setting to create minimized dataset object headers.
+ *     Result is stored at pointer `minimize`.
+ *
+ * Return:
+ *
+ *     Success: SUCCEED (0) (non-negative value)
+ *     Failure: FAIL (-1) (negative value)
+ *
+ * Programmer:
+ *
+ *     Jacob Smith
+ *     15 August 2018
+ *
+ * Changes: None.
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Fget_dset_no_attrs_hint(hid_t file_id, hbool_t *minimize)
+{
+    H5VL_object_t  *vol_obj   = NULL;
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "i*b", file_id, minimize);
+
+    if(NULL == minimize)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "out pointer 'minimize' cannot be NULL")
+
+    vol_obj = (H5VL_object_t *)H5I_object_verify(file_id, H5I_FILE);
+    if(NULL == vol_obj)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
+
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_NATIVE_FILE_GET_MIN_DSET_OHDR_FLAG, minimize) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set file's dataset header minimization flag")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Fget_dset_no_attrs_hint */
+
+
+/*-------------------------------------------------------------------------
+ * Function: H5Fset_dset_no_attrs_hint
+ *
+ * Purpose:
+ *
+ *     Set the file-level setting to create minimized dataset object headers.
+ *
+ * Return:
+ *
+ *     Success: SUCCEED (0) (non-negative value)
+ *     Failure: FAIL (-1) (negative value)
+ *
+ * Programmer:
+ *
+ *     Jacob Smith
+ *     15 August 2018
+ *
+ * Changes: None.
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5Fset_dset_no_attrs_hint(hid_t file_id, hbool_t minimize)
+{
+    H5VL_object_t *vol_obj   = NULL;
+    herr_t         ret_value = SUCCEED;
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "ib", file_id, minimize);
+
+    vol_obj = (H5VL_object_t *)H5I_object_verify(file_id, H5I_FILE);
+    if(NULL == vol_obj)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid file identifier")
+
+    if(H5VL_file_optional(vol_obj, H5P_DATASET_XFER_DEFAULT, H5_REQUEST_NULL, H5VL_NATIVE_FILE_SET_MIN_DSET_OHDR_FLAG, minimize) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to set file's dataset header minimization flag")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Fset_dset_no_attrs_hint */
+
diff --git a/src/H5FDcore.c b/src/H5FDcore.c
index ec6b2a7..ed05e95 100644
--- a/src/H5FDcore.c
+++ b/src/H5FDcore.c
@@ -420,8 +420,8 @@ done:
  * Purpose:     Initialize this driver by registering the driver with the
  *              library.
  *
- * Return:      Success:    The driver ID for the core driver.
- *              Failure:    Negative.
+ * Return:      Success:    The driver ID for the core driver
+ *              Failure:    H5I_INVALID_HID
  *
  * Programmer:  Robb Matzke
  *              Thursday, July 29, 1999
@@ -433,7 +433,7 @@ H5FD_core_init(void)
 {
     hid_t ret_value = H5I_INVALID_HID;  /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
     if(H5I_VFL != H5I_get_type(H5FD_CORE_g))
         H5FD_CORE_g = H5FD_register(&H5FD_core_g, sizeof(H5FD_class_t), FALSE);
diff --git a/src/H5FDdirect.c b/src/H5FDdirect.c
index d1a8fc8..10c368a 100644
--- a/src/H5FDdirect.c
+++ b/src/H5FDdirect.c
@@ -206,30 +206,27 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:  H5FD_direct_init
+ * Function:    H5FD_direct_init
  *
- * Purpose:  Initialize this driver by registering the driver with the
- *    library.
+ * Purpose:     Initialize this driver by registering the driver with the
+ *              library.
  *
- * Return:  Success:  The driver ID for the direct driver.
- *
- *    Failure:  Negative.
+ * Return:      Success:    The driver ID for the direct driver
+ *              Failure:    H5I_INVALID_HID
  *
  * Programmer:  Raymond Lu
  *              Wednesday, 20 September 2006
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
 hid_t
 H5FD_direct_init(void)
 {
-    hid_t ret_value;        /* Return value */
+    hid_t ret_value = H5I_INVALID_HID;        /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
-    if (H5I_VFL!=H5I_get_type(H5FD_DIRECT_g))
+    if (H5I_VFL != H5I_get_type(H5FD_DIRECT_g))
         H5FD_DIRECT_g = H5FD_register(&H5FD_direct_g,sizeof(H5FD_class_t),FALSE);
 
     /* Set return value */
@@ -237,7 +234,7 @@ H5FD_direct_init(void)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}
+} /* end H5FD_direct_init() */
 
 
 /*---------------------------------------------------------------------------
diff --git a/src/H5FDfamily.c b/src/H5FDfamily.c
index e52a71a..4d40cf3 100644
--- a/src/H5FDfamily.c
+++ b/src/H5FDfamily.c
@@ -171,28 +171,25 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FD_family_init
+ * Function:    H5FD_family_init
  *
- * Purpose:	Initialize this driver by registering the driver with the
- *		library.
+ * Purpose:     Initialize this driver by registering the driver with the
+ *              library.
  *
- * Return:	Success:	The driver ID for the family driver.
+ * Return:      Success:    The driver ID for the family driver
+ *              Failure:    H5I_INVALID_HID
  *
- *		Failure:	Negative
- *
- * Programmer:	Robb Matzke
+ * Programmer:  Robb Matzke
  *              Wednesday, August  4, 1999
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
 hid_t
 H5FD_family_init(void)
 {
-    hid_t ret_value = H5FD_FAMILY_g;   /* Return value */
+    hid_t ret_value = H5I_INVALID_HID;   /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
     if(H5I_VFL != H5I_get_type(H5FD_FAMILY_g))
         H5FD_FAMILY_g = H5FD_register(&H5FD_family_g, sizeof(H5FD_class_t), FALSE);
diff --git a/src/H5FDlog.c b/src/H5FDlog.c
index cd9ab0e..97d1b41 100644
--- a/src/H5FDlog.c
+++ b/src/H5FDlog.c
@@ -252,8 +252,8 @@ done:
  * Purpose:     Initialize this driver by registering the driver with the
  *              library.
  *
- * Return:      Success:    The driver ID for the log driver.
- *              Failure:    Negative.
+ * Return:      Success:    The driver ID for the log driver
+ *              Failure:    H5I_INVALID_HID
  *
  * Programmer:  Robb Matzke
  *              Thursday, July 29, 1999
@@ -265,7 +265,7 @@ H5FD_log_init(void)
 {
     hid_t ret_value = H5I_INVALID_HID;  /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
     if(H5I_VFL != H5I_get_type(H5FD_LOG_g))
         H5FD_LOG_g = H5FD_register(&H5FD_log_g, sizeof(H5FD_class_t), FALSE);
diff --git a/src/H5FDmpio.c b/src/H5FDmpio.c
index c04906e..a5180d0 100644
--- a/src/H5FDmpio.c
+++ b/src/H5FDmpio.c
@@ -187,15 +187,15 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FD_mpio_init
+ * Function:    H5FD_mpio_init
  *
- * Purpose:	Initialize this driver by registering the driver with the
- *		library.
+ * Purpose:     Initialize this driver by registering the driver with the
+ *              library.
  *
- * Return:	Success:	The driver ID for the mpio driver.
- *		Failure:	Negative.
+ * Return:      Success:    The driver ID for the mpio driver
+ *              Failure:    H5I_INVALID_HID
  *
- * Programmer:	Robb Matzke
+ * Programmer:  Robb Matzke
  *              Thursday, August 5, 1999
  *
  *-------------------------------------------------------------------------
@@ -206,10 +206,10 @@ H5FD_mpio_init(void)
 #ifdef H5FDmpio_DEBUG
     static int H5FD_mpio_Debug_inited = 0;
 #endif /* H5FDmpio_DEBUG */
-    const char *s;              /* String for environment variables */
-    hid_t ret_value;        	/* Return value */
+    const char *s;                          /* String for environment variables */
+    hid_t ret_value = H5I_INVALID_HID;      /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
     /* Register the MPI-IO VFD, if it isn't already */
     if(H5I_VFL != H5I_get_type(H5FD_MPIO_g))
@@ -217,8 +217,10 @@ H5FD_mpio_init(void)
 
     /* Allow MPI buf-and-file-type optimizations? */
     s = HDgetenv("HDF5_MPI_OPT_TYPES");
-    if(s && HDisdigit(*s))
-        H5FD_mpi_opt_types_g = (hbool_t)HDstrtol(s, NULL, 0);
+    if(s && HDisdigit(*s)) {
+        long env_val = HDstrtol(s, NULL, 0);
+        H5FD_mpi_opt_types_g = (0 == env_val) ? FALSE : TRUE;
+    }
 
 #ifdef H5FDmpio_DEBUG
     if(!H5FD_mpio_Debug_inited) {
@@ -226,12 +228,12 @@ H5FD_mpio_init(void)
         s = HDgetenv("H5FD_mpio_Debug");
         if(s) {
             /* Set debug mask */
-	    while(*s) {
-		H5FD_mpio_Debug[(int)*s]++;
-		s++;
-	    } /* end while */
+            while(*s) {
+                H5FD_mpio_Debug[(int)*s]++;
+                s++;
+            } /* end while */
         } /* end if */
-	H5FD_mpio_Debug_inited++;
+        H5FD_mpio_Debug_inited++;
     } /* end if */
 #endif /* H5FDmpio_DEBUG */
 
diff --git a/src/H5FDmulti.c b/src/H5FDmulti.c
index e8dde50..fac0909 100644
--- a/src/H5FDmulti.c
+++ b/src/H5FDmulti.c
@@ -26,11 +26,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-/* Disable certain warnings in PC-Lint: */
-/*lint --emacro( {534, 830}, H5P_DEFAULT, H5P_FILE_ACCESS, H5P_DATASET_XFER) */
-/*lint --emacro( {534, 830}, H5FD_MULTI) */
-/*lint -esym( 534, H5Eclear2, H5Epush2) */
-
 #include "hdf5.h"
 
 
@@ -211,16 +206,15 @@ my_strdup(const char *s)
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5FD_multi_init
- *
- * Purpose:	Initialize this driver by registering the driver with the
- *		library.
+ * Function:    H5FD_multi_init
  *
- * Return:	Success:	The driver ID for the multi driver.
+ * Purpose:     Initialize this driver by registering the driver with the
+ *              library.
  *
- *		Failure:	Negative
+ * Return:      Success:    The driver ID for the multi driver
+ *              Failure:    H5I_INVALID_HID
  *
- * Programmer:	Robb Matzke
+ * Programmer:  Robb Matzke
  *              Wednesday, August  4, 1999
  *
  *-------------------------------------------------------------------------
@@ -231,11 +225,11 @@ H5FD_multi_init(void)
     /* Clear the error stack */
     H5Eclear2(H5E_DEFAULT);
 
-    if(H5I_VFL!=H5Iget_type(H5FD_MULTI_g))
+    if(H5I_VFL != H5Iget_type(H5FD_MULTI_g))
         H5FD_MULTI_g = H5FDregister(&H5FD_multi_g);
 
     return H5FD_MULTI_g;
-}
+} /* end H5FD_multi_init() */
 
 
 /*---------------------------------------------------------------------------
diff --git a/src/H5FDsec2.c b/src/H5FDsec2.c
index 06c008d..c507387 100644
--- a/src/H5FDsec2.c
+++ b/src/H5FDsec2.c
@@ -208,8 +208,8 @@ done:
  * Purpose:     Initialize this driver by registering the driver with the
  *              library.
  *
- * Return:      Success:    The driver ID for the sec2 driver.
- *              Failure:    Negative
+ * Return:      Success:    The driver ID for the sec2 driver
+ *              Failure:    H5I_INVALID_HID
  *
  * Programmer:  Robb Matzke
  *              Thursday, July 29, 1999
@@ -221,7 +221,7 @@ H5FD_sec2_init(void)
 {
     hid_t ret_value = H5I_INVALID_HID;          /* Return value */
 
-    FUNC_ENTER_NOAPI(FAIL)
+    FUNC_ENTER_NOAPI(H5I_INVALID_HID)
 
     if(H5I_VFL != H5I_get_type(H5FD_SEC2_g))
         H5FD_SEC2_g = H5FD_register(&H5FD_sec2_g, sizeof(H5FD_class_t), FALSE);
diff --git a/src/H5Fint.c b/src/H5Fint.c
index 8de1769..cca46d0 100644
--- a/src/H5Fint.c
+++ b/src/H5Fint.c
@@ -3715,3 +3715,27 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5F_get_file_id() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_set_min_dset_ohdr
+ *
+ * Purpose:     Set the crt_dset_ohdr_flag field with a new value.
+ *
+ * Return:      SUCCEED/FAIL
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5F_set_min_dset_ohdr(H5F_t *f, hbool_t minimize)
+{
+    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Sanity check */
+    HDassert(f);
+    HDassert(f->shared);
+
+    f->shared->crt_dset_min_ohdr_flag = minimize;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5F_set_min_dset_ohdr() */
+
diff --git a/src/H5Fpkg.h b/src/H5Fpkg.h
index 4ad2c55..335d0a7 100644
--- a/src/H5Fpkg.h
+++ b/src/H5Fpkg.h
@@ -358,6 +358,7 @@ struct H5F_file_t {
 
     /* Object flush info */
     H5F_object_flush_t 	object_flush;	    /* Information for object flush callback */
+    hbool_t crt_dset_min_ohdr_flag; /* flag to minimize created dataset object header */
 };
 
 /*
@@ -382,7 +383,6 @@ struct H5F_t {
 #endif /* H5_HAVE_PARALLEL */
 };
 
-
 /*****************************/
 /* Package Private Variables */
 /*****************************/
diff --git a/src/H5Fprivate.h b/src/H5Fprivate.h
index 85f0d15..5f7a1b2 100644
--- a/src/H5Fprivate.h
+++ b/src/H5Fprivate.h
@@ -331,6 +331,8 @@ typedef struct H5F_t H5F_t;
 #define H5F_POINT_OF_NO_RETURN(F) ((F)->shared->fs.point_of_no_return)
 #define H5F_FIRST_ALLOC_DEALLOC(F) ((F)->shared->first_alloc_dealloc)
 #define H5F_EOA_PRE_FSM_FSALLOC(F) ((F)->shared->eoa_pre_fsm_fsalloc)
+#define H5F_GET_MIN_DSET_OHDR(F) ((F)->shared->crt_dset_min_ohdr_flag)
+#define H5F_SET_MIN_DSET_OHDR(F, V) ((F)->shared->crt_dset_min_ohdr_flag = (V))
 #else /* H5F_MODULE */
 #define H5F_LOW_BOUND(F)        (H5F_get_low_bound(F))
 #define H5F_HIGH_BOUND(F)       (H5F_get_high_bound(F))
@@ -388,6 +390,8 @@ typedef struct H5F_t H5F_t;
 #define H5F_POINT_OF_NO_RETURN(F) (H5F_get_point_of_no_return(F))
 #define H5F_FIRST_ALLOC_DEALLOC(F) (H5F_get_first_alloc_dealloc(F))
 #define H5F_EOA_PRE_FSM_FSALLOC(F) (H5F_get_eoa_pre_fsm_fsalloc(F))
+#define H5F_GET_MIN_DSET_OHDR(F) (H5F_get_min_dset_ohdr(F))
+#define H5F_SET_MIN_DSET_OHDR(F, V) (H5F_set_min_dset_ohdr((F), (V)))
 #endif /* H5F_MODULE */
 
 
@@ -740,6 +744,8 @@ H5_DLL hsize_t H5F_get_pgend_meta_thres(const H5F_t *f);
 H5_DLL hbool_t H5F_get_point_of_no_return(const H5F_t *f);
 H5_DLL hbool_t H5F_get_first_alloc_dealloc(const H5F_t *f);
 H5_DLL haddr_t H5F_get_eoa_pre_fsm_fsalloc(const H5F_t *f);
+H5_DLL hbool_t H5F_get_min_dset_ohdr(const H5F_t *f);
+H5_DLL herr_t H5F_set_min_dset_ohdr(H5F_t *f, hbool_t minimize);
 
 /* Functions than retrieve values set/cached from the superblock/FCPL */
 H5_DLL haddr_t H5F_get_base_addr(const H5F_t *f);
diff --git a/src/H5Fpublic.h b/src/H5Fpublic.h
index e1b6dc3..c4bf0b4 100644
--- a/src/H5Fpublic.h
+++ b/src/H5Fpublic.h
@@ -217,7 +217,6 @@ typedef struct H5F_retry_info_t {
 /* Callback for H5Pset_object_flush_cb() in a file access property list */
 typedef herr_t (*H5F_flush_cb_t)(hid_t object_id, void *udata);
 
-
 /*********************/
 /* Public Prototypes */
 /*********************/
@@ -275,6 +274,8 @@ H5_DLL herr_t H5Freset_page_buffering_stats(hid_t file_id);
 H5_DLL herr_t H5Fget_page_buffering_stats(hid_t file_id, unsigned accesses[2],
     unsigned hits[2], unsigned misses[2], unsigned evictions[2], unsigned bypasses[2]);
 H5_DLL herr_t H5Fget_mdc_image_info(hid_t file_id, haddr_t *image_addr, hsize_t *image_size);
+H5_DLL herr_t H5Fget_dset_no_attrs_hint(hid_t file_id, hbool_t *minimize);
+H5_DLL herr_t H5Fset_dset_no_attrs_hint(hid_t file_id, hbool_t minimize);
 
 #ifdef H5_HAVE_PARALLEL
 H5_DLL herr_t H5Fset_mpi_atomicity(hid_t file_id, hbool_t flag);
diff --git a/src/H5Fquery.c b/src/H5Fquery.c
index 3147e95..103ad3b 100644
--- a/src/H5Fquery.c
+++ b/src/H5Fquery.c
@@ -514,6 +514,25 @@ H5F_sym_leaf_k(const H5F_t *f)
 
 
 /*-------------------------------------------------------------------------
+ * Function: H5F_get_min_dset_ohdr
+ *
+ * Purpose:  Get the setting flag for minimized dataset object headers
+ *
+ * Return:   TRUE/FALSE as set in file
+ *-------------------------------------------------------------------------
+ */
+hbool_t
+H5F_get_min_dset_ohdr(const H5F_t *f)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    HDassert(f);
+
+    FUNC_LEAVE_NOAPI(f->shared->crt_dset_min_ohdr_flag)
+} /* end H5F_get_min_dset_ohdr */
+
+
+/*-------------------------------------------------------------------------
  * Function: H5F_Kvalue
  *
  * Purpose:  Replaced a macro to retrieve a B-tree key value for a certain
diff --git a/src/H5Oint.c b/src/H5Oint.c
index a97a2fd..2503eb7 100644
--- a/src/H5Oint.c
+++ b/src/H5Oint.c
@@ -83,7 +83,6 @@ static herr_t H5O__visit_cb(hid_t group, const char *name, const H5L_info_t *lin
     void *_udata);
 static const H5O_obj_class_t *H5O__obj_class_real(const H5O_t *oh);
 
-
 /*********************/
 /* Package Variables */
 /*********************/
@@ -277,99 +276,183 @@ done:
  *		matzke@llnl.gov
  *		Aug  5 1997
  *
+ * Changes:     2018 August 17
+ *              Jacob Smith 
+ *              Refactor out the operations into two separate steps --
+ *              preparation and application -- to facilitate overriding the
+ *              library-default size allocated for the object header. This
+ *              function is retained as a wrapper, to minimize changes to
+ *              unaffected calling functions.
+ *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc, hid_t ocpl_id,
-    H5O_loc_t *loc/*out*/)
+H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc, hid_t ocpl_id, H5O_loc_t *loc /*out*/)
 {
-    H5P_genplist_t  *oc_plist;          /* Object creation property list */
-    H5O_t      *oh = NULL;              /* Object header created */
-    haddr_t     oh_addr;                /* Address of initial object header */
-    size_t      oh_size;                /* Size of initial object header */
-    uint8_t	oh_flags;		/* Object header's initial status flags */
-    unsigned    insert_flags = H5AC__NO_FLAGS_SET; /* Flags for inserting object header into cache */
-    hbool_t     store_msg_crt_idx;      /* Whether to always store message creation indices for this file */
-    herr_t      ret_value = SUCCEED;    /* return value */
+    H5O_t  *oh        = NULL;
+    herr_t  ret_value = SUCCEED;
 
     FUNC_ENTER_NOAPI(FAIL)
 
-    /* check args */
     HDassert(f);
     HDassert(loc);
     HDassert(TRUE == H5P_isa_class(ocpl_id, H5P_OBJECT_CREATE));
 
+    /* create object header in freelist
+     * header version is set internally
+     */
+    oh = H5O__create_ohdr(f, ocpl_id);
+    if(NULL == oh)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "Can't instantiate object header")
+
+    /* apply object header information to file
+     */
+    if(H5O__apply_ohdr(f, oh, ocpl_id, size_hint, initial_rc, loc) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "Can't apply object header to file")
+
+done:
+    if((FAIL == ret_value) && (NULL != oh) && (H5O__free(oh) < 0))
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "can't delete object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_create() */
+
+
+/*-----------------------------------------------------------------------------
+ * Function:   H5O__create_ohdr
+ *
+ * Purpose:    Create the object header, set version and flags.
+ *
+ * Return:     Success: Pointer to the newly-crated header object.
+ *             Failure: NULL
+ *
+ * Programmer: Jacob Smith
+ *             2018 August 17 
+ *
+ *-----------------------------------------------------------------------------
+ */
+H5O_t *
+H5O__create_ohdr(H5F_t *f, hid_t ocpl_id)
+{
+    H5P_genplist_t *oc_plist;
+    H5O_t          *oh = NULL;        /* Object header in Freelist */
+    uint8_t         oh_flags;         /* Initial status flags */
+    H5O_t          *ret_value = NULL;
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    HDassert(f);
+    HDassert(TRUE == H5P_isa_class(ocpl_id, H5P_OBJECT_CREATE));
+
     /* Check for invalid access request */
     if(0 == (H5F_INTENT(f) & H5F_ACC_RDWR))
-        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "no write intent on file")
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "no write intent on file")
 
-    /* Make certain we allocate at least a reasonable size for the object header */
-    size_hint = H5O_ALIGN_F(f, MAX(H5O_MIN_SIZE, size_hint));
+    oh = H5FL_CALLOC(H5O_t);
+    if(NULL == oh)
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
 
-    /* Get the property list */
-    if(NULL == (oc_plist = (H5P_genplist_t *)H5I_object(ocpl_id)))
-        HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, FAIL, "not a property list")
+    oc_plist = (H5P_genplist_t *)H5I_object(ocpl_id);
+    if(NULL == oc_plist)
+        HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, NULL, "not a property list")
 
     /* Get any object header status flags set by properties */
     if(H5P_get(oc_plist, H5O_CRT_OHDR_FLAGS_NAME, &oh_flags) < 0)
-        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get object header flags")
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get object header flags")
 
-    /* Allocate the object header and zero out header fields */
-    if(NULL == (oh = H5FL_CALLOC(H5O_t)))
-        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+    if(H5O_set_version(f, oh, oh_flags, H5F_STORE_MSG_CRT_IDX(f)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, NULL, "can't set version of object header")
+
+    oh->flags = oh_flags;
+
+    ret_value = oh;
+
+done:
+    if((NULL == ret_value) && (NULL != oh) && (H5O__free(oh) < 0))
+        HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, NULL, "can't delete object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5O__create_ohdr() */
 
-    /* Initialize file-specific information for object header */
-    store_msg_crt_idx = H5F_STORE_MSG_CRT_IDX(f);
+
+/*-----------------------------------------------------------------------------
+ * Function:   H5O__apply_ohdr
+ *
+ * Purpose:    Initialize and set the object header in the file.
+ *             Record some information at `loc_out`.
+ *
+ * Return:     Success: SUCCEED (0) (non-negative value)
+ *             Failure: FAIL (-1) (negative value)
+ *
+ * Programmer: Jacob Smith
+ *             2018 August 17
+ *
+ *-----------------------------------------------------------------------------
+ */
+herr_t
+H5O__apply_ohdr(H5F_t *f, H5O_t *oh, hid_t ocpl_id, size_t size_hint, size_t initial_rc, H5O_loc_t *loc_out)
+{
+    haddr_t         oh_addr;
+    size_t          oh_size;
+    H5P_genplist_t *oc_plist     = NULL;
+    unsigned        insert_flags = H5AC__NO_FLAGS_SET;
+    herr_t          ret_value    = SUCCEED;
 
-    if(H5O_set_version(f, oh, oh_flags, store_msg_crt_idx) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "can't set version of objecdt header")
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert(f);
+    HDassert(loc_out);
+    HDassert(oh);
+    HDassert(TRUE == H5P_isa_class(ocpl_id, H5P_OBJECT_CREATE));
+
+    /* Allocate at least a reasonable size for the object header */
+    size_hint = H5O_ALIGN_F(f, MAX(H5O_MIN_SIZE, size_hint));
 
     oh->sizeof_size = H5F_SIZEOF_SIZE(f);
     oh->sizeof_addr = H5F_SIZEOF_ADDR(f);
-    oh->swmr_write = !!(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE);
+    oh->swmr_write = !!(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE); /* funky cast */
+
 #ifdef H5O_ENABLE_BAD_MESG_COUNT
     /* Check whether the "bad message count" property is set */
-    if(H5P_exist_plist(oc_plist, H5O_BAD_MESG_COUNT_NAME) > 0) {
-        /* Retrieve bad message count flag */
+    if(0 < H5P_exist_plist(oc_plist, H5O_BAD_MESG_COUNT_NAME))
+        /* Get bad message count flag -- from property list */
         if(H5P_get(oc_plist, H5O_BAD_MESG_COUNT_NAME, &oh->store_bad_mesg_count) < 0)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't get bad message count flag")
-    }
 #endif /* H5O_ENABLE_BAD_MESG_COUNT */
 
     /* Create object header proxy if doing SWMR writes */
     if(oh->swmr_write) {
-        /* Create virtual entry, for use as proxy */
-        if(NULL == (oh->proxy = H5AC_proxy_entry_create()))
+        oh->proxy = H5AC_proxy_entry_create();
+        if(NULL == oh->proxy)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "can't create object header proxy")
-    }
-    else
+    } else {
         oh->proxy = NULL;
+    }
 
-    /* Set initial status flags */
-    oh->flags = oh_flags;
+    oc_plist = (H5P_genplist_t *)H5I_object(ocpl_id);
+    if(NULL == oc_plist)
+        HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, FAIL, "not a property list")
 
     /* Initialize version-specific fields */
     if(oh->version > H5O_VERSION_1) {
-        /* Initialize all time fields with current time, if we are storing them */
+        /* Initialize all time fields */
         if(oh->flags & H5O_HDR_STORE_TIMES)
             oh->atime = oh->mtime = oh->ctime = oh->btime = H5_now();
         else
             oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
 
-        /* Make certain attribute creation order tracking is enabled if
-         *      attributes can be shared in this file.
-         */
-        if(store_msg_crt_idx)
+        if(H5F_STORE_MSG_CRT_IDX(f))
+            /* flag to record message creation indices */
             oh->flags |= H5O_HDR_ATTR_CRT_ORDER_TRACKED;
 
-        /* Retrieve attribute storage phase change values from property list */
+        /* Get attribute storage phase change values -- from property list */
         if(H5P_get(oc_plist, H5O_CRT_ATTR_MAX_COMPACT_NAME, &oh->max_compact) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get max. # of compact attributes")
         if(H5P_get(oc_plist, H5O_CRT_ATTR_MIN_DENSE_NAME, &oh->min_dense) < 0)
             HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get min. # of dense attributes")
 
         /* Check for non-default attribute storage phase change values */
-        if(oh->max_compact != H5O_CRT_ATTR_MAX_COMPACT_DEF || oh->min_dense != H5O_CRT_ATTR_MIN_DENSE_DEF)
+        if(H5O_CRT_ATTR_MAX_COMPACT_DEF != oh->max_compact  || H5O_CRT_ATTR_MIN_DENSE_DEF != oh->min_dense )
             oh->flags |= H5O_HDR_ATTR_STORE_PHASE_CHANGE;
 
         /* Determine correct value for chunk #0 size bits */
@@ -383,23 +466,25 @@ H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc, hid_t ocpl_id,
             oh->flags |= H5O_HDR_CHUNK0_4;
         else if(size_hint > 255)
             oh->flags |= H5O_HDR_CHUNK0_2;
-    } /* end if */
-    else {
+    } else {
         /* Reset unused time fields */
         oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
-    } /* end else */
+    } /* end if/else header version >1 */
 
     /* Compute total size of initial object header */
     /* (i.e. object header prefix and first chunk) */
     oh_size = (size_t)H5O_SIZEOF_HDR(oh) + size_hint;
 
     /* Allocate disk space for header and first chunk */
-    if(HADDR_UNDEF == (oh_addr = H5MF_alloc(f, H5FD_MEM_OHDR, (hsize_t)oh_size)))
+    oh_addr = H5MF_alloc(f, H5FD_MEM_OHDR, (hsize_t)oh_size);
+    if(HADDR_UNDEF == oh_addr)
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "file allocation failed for object header")
 
     /* Create the chunk list */
-    oh->nchunks = oh->alloc_nchunks = 1;
-    if(NULL == (oh->chunk = H5FL_SEQ_MALLOC(H5O_chunk_t, (size_t)oh->alloc_nchunks)))
+    oh->nchunks = 1;
+    oh->alloc_nchunks = 1;
+    oh->chunk = H5FL_SEQ_MALLOC(H5O_chunk_t, (size_t)oh->alloc_nchunks);
+    if(NULL == oh->chunk)
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
 
     /* Initialize the first chunk */
@@ -409,25 +494,27 @@ H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc, hid_t ocpl_id,
 
     /* Allocate enough space for the first chunk */
     /* (including space for serializing the object header prefix */
-    if(NULL == (oh->chunk[0].image = H5FL_BLK_CALLOC(chunk_image, oh_size)))
+    oh->chunk[0].image = H5FL_BLK_CALLOC(chunk_image, oh_size);
+    if(NULL == oh->chunk[0].image)
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
     oh->chunk[0].chunk_proxy = NULL;
 
     /* Put magic # for object header in first chunk */
-    if(oh->version > H5O_VERSION_1)
+    if(H5O_VERSION_1 < oh->version)
         HDmemcpy(oh->chunk[0].image, H5O_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
 
     /* Create the message list */
     oh->nmesgs = 1;
     oh->alloc_nmesgs = H5O_NMESGS;
-    if(NULL == (oh->mesg = H5FL_SEQ_CALLOC(H5O_mesg_t, oh->alloc_nmesgs)))
+    oh->mesg = H5FL_SEQ_CALLOC(H5O_mesg_t, oh->alloc_nmesgs);
+    if(NULL == oh->mesg)
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
 
-    /* Initialize the initial "null" message, covering the entire first chunk */
+    /* Initialize the initial "null" message; covers the entire first chunk */
     oh->mesg[0].type = H5O_MSG_NULL;
     oh->mesg[0].dirty = TRUE;
     oh->mesg[0].native = NULL;
-    oh->mesg[0].raw = oh->chunk[0].image + (H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh)) + H5O_SIZEOF_MSGHDR_OH(oh);
+    oh->mesg[0].raw = oh->chunk[0].image + H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh) + H5O_SIZEOF_MSGHDR_OH(oh);
     oh->mesg[0].raw_size = size_hint - (size_t)H5O_SIZEOF_MSGHDR_OH(oh);
     oh->mesg[0].chunkno = 0;
 
@@ -452,20 +539,15 @@ H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc, hid_t ocpl_id,
     H5_END_TAG
 
     /* Set up object location */
-    loc->file = f;
-    loc->addr = oh_addr;
+    loc_out->file = f;
+    loc_out->addr = oh_addr;
 
-    /* Open it */
-    if(H5O_open(loc) < 0)
+    if(H5O_open(loc_out) < 0)
         HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open object header")
 
 done:
-    if(ret_value < 0 && oh)
-        if(H5O__free(oh) < 0)
-            HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header data")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5O_create() */
+    FUNC_LEAVE_NOAPI(ret_value);
+} /* H5O__apply_ohdr() */
 
 
 /*-------------------------------------------------------------------------
@@ -2420,6 +2502,63 @@ H5O_get_oh_addr(const H5O_t *oh)
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5O_get_oh_flags
+ *
+ * Programmer:	Jacob Smith
+ *		2018 August 17
+ *
+ *-------------------------------------------------------------------------
+ */
+uint8_t
+H5O_get_oh_flags(const H5O_t *oh)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    HDassert(oh);
+    FUNC_LEAVE_NOAPI(oh->flags); /* flags can be 0 */
+} /* H5O_get_oh_flags() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_oh_mtime
+ *
+ * Purpose:	Retrieve an object's modification time. Assumes that the
+ *              caller has verified that accessing this variable is appropriate
+ *              to the header in question.
+ *
+ * Programmer:	Jacob Smith
+ *		2018 August 17
+ *
+ *-------------------------------------------------------------------------
+ */
+time_t
+H5O_get_oh_mtime(const H5O_t *oh)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    HDassert(oh);
+    HDassert(oh->mtime);
+    FUNC_LEAVE_NOAPI(oh->mtime);
+} /* H5O_get_oh_mtime() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_oh_version
+ *
+ * Programmer:	Jacob Smith
+ *		2018 August 17
+ *
+ *-------------------------------------------------------------------------
+ */
+uint8_t
+H5O_get_oh_version(const H5O_t *oh)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+    HDassert(oh);
+    HDassert(oh->version);
+    FUNC_LEAVE_NOAPI(oh->version);
+} /* H5O_get_oh_version() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5O_get_rc_and_type
  *
  * Purpose:	Retrieve an object's reference count and type
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index 7ed9e26..e0926e2 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -121,8 +121,14 @@ typedef struct H5O_mesg_t H5O_mesg_t;
 /* If the module using this macro is allowed access to the private variables, access them directly */
 #ifdef H5O_MODULE
 #define H5O_OH_GET_ADDR(O)    ((O)->chunk[0].addr)
+#define H5O_OH_GET_VERSION(O) ((O)->version)
+#define H5O_OH_GET_FLAGS(O)   ((O)->flags)
+#define H5O_OH_GET_MTIME(O)   ((O)->mtime)
 #else /* H5O_MODULE */
 #define H5O_OH_GET_ADDR(O)    (H5O_get_oh_addr(O))
+#define H5O_OH_GET_VERSION(O) (H5O_get_oh_version(O))
+#define H5O_OH_GET_FLAGS(O)   (H5O_get_oh_flags(O))
+#define H5O_OH_GET_MTIME(O)   (H5O_get_oh_mtime(O))
 #endif /* H5O_MODULE */
 
 /* Set the fields in a shared message structure */
@@ -865,6 +871,9 @@ struct H5P_genplist_t;
 H5_DLL herr_t H5O_init(void);
 H5_DLL herr_t H5O_create(H5F_t *f, size_t size_hint, size_t initial_rc,
     hid_t ocpl_id, H5O_loc_t *loc/*out*/);
+H5_DLL H5O_t *H5O__create_ohdr(H5F_t *f, hid_t ocpl_id);
+H5_DLL herr_t H5O__apply_ohdr(H5F_t *f, H5O_t *oh, hid_t ocpl_id,
+    size_t size_hint, size_t initial_rc, H5O_loc_t *loc_out);
 H5_DLL herr_t H5O_open(H5O_loc_t *loc);
 H5_DLL void *H5O_open_by_idx(const H5G_loc_t *loc, const char *name,
     H5_index_t idx_type, H5_iter_order_t order, hsize_t n, H5I_type_t *opened_type/*out*/);
@@ -891,6 +900,9 @@ H5_DLL void *H5O_open_name(const H5G_loc_t *loc, const char *name, H5I_type_t *o
 H5_DLL herr_t H5O_get_nlinks(const H5O_loc_t *loc, hsize_t *nlinks);
 H5_DLL void *H5O_obj_create(H5F_t *f, H5O_type_t obj_type, void *crt_info, H5G_loc_t *obj_loc);
 H5_DLL haddr_t H5O_get_oh_addr(const H5O_t *oh);
+H5_DLL uint8_t H5O_get_oh_flags(const H5O_t *oh);
+H5_DLL time_t H5O_get_oh_mtime(const H5O_t *oh);
+H5_DLL uint8_t H5O_get_oh_version(const H5O_t *oh);
 H5_DLL herr_t H5O_get_rc_and_type(const H5O_loc_t *oloc, unsigned *rc, H5O_type_t *otype);
 H5_DLL H5AC_proxy_entry_t *H5O_get_proxy(const H5O_t *oh);
 
diff --git a/src/H5Pdcpl.c b/src/H5Pdcpl.c
index a5a16bb..b85f105 100644
--- a/src/H5Pdcpl.c
+++ b/src/H5Pdcpl.c
@@ -117,6 +117,11 @@
 #define H5D_CRT_EXT_FILE_LIST_COPY H5P__dcrt_ext_file_list_copy
 #define H5D_CRT_EXT_FILE_LIST_CMP  H5P__dcrt_ext_file_list_cmp
 #define H5D_CRT_EXT_FILE_LIST_CLOSE H5P__dcrt_ext_file_list_close
+/* Definitions for dataset object header minimization */
+#define H5D_CRT_MIN_DSET_HDR_SIZE_SIZE sizeof(hbool_t)
+#define H5D_CRT_MIN_DSET_HDR_SIZE_DEF  FALSE
+#define H5D_CRT_MIN_DSET_HDR_SIZE_ENC  H5P__encode_hbool_t
+#define H5D_CRT_MIN_DSET_HDR_SIZE_DEC  H5P__decode_hbool_t
 
 
 /******************/
@@ -209,6 +214,7 @@ static const H5O_layout_t H5D_def_layout_g = H5D_CRT_LAYOUT_DEF;        /* Defau
 static const H5O_fill_t H5D_def_fill_g = H5D_CRT_FILL_VALUE_DEF;        /* Default fill value */
 static const unsigned H5D_def_alloc_time_state_g = H5D_CRT_ALLOC_TIME_STATE_DEF;  /* Default allocation time state */
 static const H5O_efl_t H5D_def_efl_g = H5D_CRT_EXT_FILE_LIST_DEF;                 /* Default external file list */
+static const unsigned H5O_ohdr_min_g = H5D_CRT_MIN_DSET_HDR_SIZE_DEF; /* Default object header minimization */
 
 /* Defaults for each type of layout */
 #ifdef H5_HAVE_C99_DESIGNATED_INITIALIZER
@@ -271,6 +277,12 @@ H5P__dcrt_reg_prop(H5P_genclass_t *pclass)
             H5D_CRT_EXT_FILE_LIST_DEL, H5D_CRT_EXT_FILE_LIST_COPY, H5D_CRT_EXT_FILE_LIST_CMP, H5D_CRT_EXT_FILE_LIST_CLOSE) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
 
+    /* Register the object header minimization property */
+    if(H5P__register_real(pclass, H5D_CRT_MIN_DSET_HDR_SIZE_NAME, H5D_CRT_MIN_DSET_HDR_SIZE_SIZE, &H5O_ohdr_min_g,
+            NULL, NULL, NULL, H5D_CRT_MIN_DSET_HDR_SIZE_ENC, H5D_CRT_MIN_DSET_HDR_SIZE_DEC,
+            NULL, NULL, NULL, NULL) < 0)
+       HGOTO_ERROR(H5E_PLIST, H5E_CANTINSERT, FAIL, "can't insert property into class")
+
     /* Register the type ID property*/
     if(H5P__register_real(pclass, H5VL_PROP_DSET_TYPE_ID, sizeof(hid_t), &type_id, 
                          NULL, NULL, NULL, NULL, NULL, NULL, NULL, H5P_ignore_cmp, NULL) < 0)
@@ -3749,3 +3761,95 @@ done:
     FUNC_LEAVE_API(ret_value)
 } /* end H5Pget_fill_time() */
 
+
+/*-----------------------------------------------------------------------------
+ * Function: H5Pget_dset_no_attrs_hint
+ *
+ * Purpose:
+ *
+ *     Access the flag for whether or not datasets created by the given dcpl
+ *     will be created with a "minimized" object header.
+ *
+ * Return:
+ *
+ *     Failure: Negative value (FAIL)
+ *     Success: Non-negative value (SUCCEED)
+ *
+ * Programmer: Jacob Smith
+ *             2018 August 14
+ *
+ * Modifications: None.
+ *
+ *-----------------------------------------------------------------------------
+ */
+herr_t
+H5Pget_dset_no_attrs_hint(hid_t dcpl_id, hbool_t *minimize)
+{
+    hbool_t         setting   = FALSE;
+    H5P_genplist_t *plist     = NULL;
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "i*b", dcpl_id, minimize);
+
+    if(NULL == minimize)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "receiving pointer cannot be NULL")
+
+    plist = H5P_object_verify(dcpl_id, H5P_DATASET_CREATE);
+    if(NULL == plist)
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
+
+    if(H5P_peek(plist, H5D_CRT_MIN_DSET_HDR_SIZE_NAME, &setting) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get dset oh minimize flag value")
+
+    *minimize = setting;
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Pget_dset_no_attrs_hint() */
+
+
+/*-----------------------------------------------------------------------------
+ * Function: H5Pset_dset_no_attrs_hint
+ *
+ * Purpose:
+ *
+ *     Set the dcpl to minimize (or explicitly to not minimized) dataset object
+ *     headers upon creation.
+ *
+ * Return:
+ *
+ *     Failure: Negative value (FAIL)
+ *     Success: Non-negative value (SUCCEED)
+ *
+ * Programmer: Jacob Smith
+ *             2018 August 14
+ *
+ * Modifications: None.
+ *
+ *-----------------------------------------------------------------------------
+ */
+herr_t
+H5Pset_dset_no_attrs_hint(hid_t dcpl_id, hbool_t minimize)
+{
+    H5P_genplist_t *plist     = NULL;
+    hbool_t         prev_set  = FALSE;
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_API(FAIL)
+    H5TRACE2("e", "ib", dcpl_id, minimize);
+
+    plist = H5P_object_verify(dcpl_id, H5P_DATASET_CREATE);
+    if(NULL == plist)
+        HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't find object for ID")
+
+    if(H5P_peek(plist, H5D_CRT_MIN_DSET_HDR_SIZE_NAME, &prev_set) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get extant dset oh minimize flag value")
+
+    if(H5P_poke(plist, H5D_CRT_MIN_DSET_HDR_SIZE_NAME, &minimize) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't get dset oh minimize flag value")
+
+done:
+    FUNC_LEAVE_API(ret_value)
+} /* H5Pset_dset_no_attrs_hint() */
+
diff --git a/src/H5Ppublic.h b/src/H5Ppublic.h
index 86c6687..2f094ea 100644
--- a/src/H5Ppublic.h
+++ b/src/H5Ppublic.h
@@ -412,6 +412,8 @@ H5_DLL herr_t H5Pget_alloc_time(hid_t plist_id, H5D_alloc_time_t
 H5_DLL herr_t H5Pset_fill_time(hid_t plist_id, H5D_fill_time_t fill_time);
 H5_DLL herr_t H5Pget_fill_time(hid_t plist_id, H5D_fill_time_t
     *fill_time/*out*/);
+H5_DLL herr_t H5Pget_dset_no_attrs_hint(hid_t dcpl_id, hbool_t *minimize);
+H5_DLL herr_t H5Pset_dset_no_attrs_hint(hid_t dcpl_id, hbool_t minimize);
 
 /* Dataset access property list (DAPL) routines */
 H5_DLL herr_t H5Pset_chunk_cache(hid_t dapl_id, size_t rdcc_nslots,
diff --git a/src/H5VL.c b/src/H5VL.c
index bf1201f..88d3d70 100644
--- a/src/H5VL.c
+++ b/src/H5VL.c
@@ -11,7 +11,7 @@
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
 /*
- * Purpose:	The Virtual Object Layer as described in documentation.
+ * 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...
@@ -486,14 +486,11 @@ done:
 /*---------------------------------------------------------------------------
  * Function:    H5VLcmp_connector_cls
  *
- * Purpose:     Compares two connector classes
+ * Purpose:     Compares two connector classes (based on their value field)
  *
- * Return:      Success:    Non-negative, with *cmp set to positive if
- *		connector_id1 is greater than connector_id2, negative if connector_id2
- *		is greater than connector_id1 and zero if connector_id1 and connector_id2
- *		are equal.
+ * Return:      Success:    Non-negative, *cmp set to a value like strcmp
  *
- *              Failure:    Negative
+ *              Failure:    Negative, *cmp unset
  *
  *---------------------------------------------------------------------------
  */
diff --git a/src/H5VLint.c b/src/H5VLint.c
index d51be0c..8695a80 100644
--- a/src/H5VLint.c
+++ b/src/H5VLint.c
@@ -881,7 +881,7 @@ done:
  *
  * Return:      Positive if VALUE1 is greater than VALUE2, negative if
  *              VALUE2 is greater than VALUE1 and zero if VALUE1 and
- *              VALUE2 are equal.
+ *              VALUE2 are equal (like strcmp).
  *
  *-------------------------------------------------------------------------
  */
diff --git a/src/H5VLnative.h b/src/H5VLnative.h
index 916151b..1a3007a 100644
--- a/src/H5VLnative.h
+++ b/src/H5VLnative.h
@@ -66,6 +66,8 @@ typedef int H5VL_native_file_optional_t;
 #define H5VL_NATIVE_FILE_GET_EOA                        22  /* H5Fget_eoa                           */
 #define H5VL_NATIVE_FILE_INCR_FILESIZE                  23  /* H5Fincrement_filesize                */
 #define H5VL_NATIVE_FILE_SET_LIBVER_BOUNDS              24  /* H5Fset_latest_format/libver_bounds   */
+#define H5VL_NATIVE_FILE_GET_MIN_DSET_OHDR_FLAG         25  /* H5Fget_dset_no_attrs_hint            */
+#define H5VL_NATIVE_FILE_SET_MIN_DSET_OHDR_FLAG         26  /* H5Fset_dset_no_attrs_hint            */
 
 /* Typedef and values for native VOL connector group optional VOL operations */
 typedef int H5VL_native_group_optional_t;
diff --git a/src/H5VLnative_file.c b/src/H5VLnative_file.c
index cc21a22..e7f27e1 100644
--- a/src/H5VLnative_file.c
+++ b/src/H5VLnative_file.c
@@ -377,6 +377,8 @@ H5VL__native_file_specific(void *obj, H5VL_file_specific_t specific_type,
                 break;
             }
 
+
+
         default:
             HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "invalid specific operation")
     } /* end switch */
@@ -750,6 +752,23 @@ H5VL__native_file_optional(void *obj, hid_t H5_ATTR_UNUSED dxpl_id, void H5_ATTR
                 break;
             }
 
+        /* H5Fget_dset_no_attrs_hint */
+        case H5VL_NATIVE_FILE_GET_MIN_DSET_OHDR_FLAG:
+            {
+                hbool_t *minimize = va_arg(arguments, hbool_t *);
+                *minimize = H5F_GET_MIN_DSET_OHDR(f);
+                break;
+            }
+
+        /* H5Fset_dset_no_attrs_hint */
+        case H5VL_NATIVE_FILE_SET_MIN_DSET_OHDR_FLAG:
+            {
+                int minimize = va_arg(arguments, int);
+                if(H5F_set_min_dset_ohdr(f, (hbool_t)minimize) < 0)
+                    HGOTO_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "cannot set file's dataset object header minimization flag")
+                break;
+            }
+
         default:
             HGOTO_ERROR(H5E_VOL, H5E_UNSUPPORTED, FAIL, "invalid optional operation")
     } /* end switch */
diff --git a/src/H5VLpublic.h b/src/H5VLpublic.h
index 22cf12b..5de36c8 100644
--- a/src/H5VLpublic.h
+++ b/src/H5VLpublic.h
@@ -115,7 +115,7 @@ typedef enum H5VL_file_get_t {
     H5VL_FILE_GET_INTENT,	            /* file intent           		*/
     H5VL_FILE_GET_NAME,	                    /* file name             		*/
     H5VL_FILE_GET_OBJ_COUNT,	            /* object count in file	       	*/
-    H5VL_FILE_GET_OBJ_IDS 	            /* object ids in file     		*/
+    H5VL_FILE_GET_OBJ_IDS	            /* object ids in file     		*/
 } H5VL_file_get_t;
 
 /* types for file SPECIFIC callback */