[svn-r5840] Purpose:

    Code cleanup

Description:
    Created a new H5I function which combined the some of the functionality of
    H5I_get_type and H5I_object: H5I_object_verify.

    Using this new function in the library trims another ~200 lines of code off
    the library and makes the resulting binaries smaller and faster also.

Platforms tested:
    FreeBSD 4.6 (sleipnir)

20 files changed, 556 insertions, 790 deletions

diff --git a/src/H5A.c b/src/H5A.c
index 1157e19..42190e1 100644
--- a/src/H5A.c
+++ b/src/H5A.c
@@ -174,14 +174,10 @@ H5Acreate(hid_t loc_id, const char *name, hid_t type_id, hid_t space_id,
     if (!name || !*name) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
     }
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (type = H5I_object(type_id))) {
+    if (NULL == (type = H5I_object_verify(type_id, H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a type");
-    }
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-	NULL == (space = H5I_object(space_id))) {
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
 
     /* Go do the real work for attaching the attribute to the dataset */
     if ((ret_value=H5A_create(ent,name,type,space))<0) {
@@ -561,14 +557,10 @@ H5Awrite(hid_t attr_id, hid_t type_id, const void *buf)
     H5TRACE3("e","iix",attr_id,type_id,buf);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) ||
-	(NULL == (attr = H5I_object(attr_id)))) {
+    if (NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (mem_type = H5I_object(type_id))) {
+    if (NULL == (mem_type = H5I_object_verify(type_id, H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (NULL == buf) {
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "null attribute buffer");
     }
@@ -715,14 +707,10 @@ H5Aread(hid_t attr_id, hid_t type_id, void *buf)
     H5TRACE3("e","iix",attr_id,type_id,buf);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) ||
-	(NULL == (attr = H5I_object(attr_id)))) {
+    if (NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (mem_type = H5I_object(type_id))) {
+    if (NULL == (mem_type = H5I_object_verify(type_id, H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (NULL == buf) {
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "null attribute buffer");
     }
@@ -860,10 +848,8 @@ H5Aget_space(hid_t attr_id)
     H5TRACE1("i","i",attr_id);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) ||
-	(NULL == (attr = H5I_object(attr_id)))) {
+    if (NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
 
     /* Copy the attribute's dataspace */
     if (NULL==(dst=H5S_copy (attr->ds))) {
@@ -917,10 +903,8 @@ H5Aget_type(hid_t attr_id)
     H5TRACE1("i","i",attr_id);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) ||
-	(NULL == (attr = H5I_object(attr_id)))) {
+    if (NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
 
     /*
      * Copy the attribute's data type.  If the type is a named type then
@@ -987,10 +971,8 @@ H5Aget_name(hid_t attr_id, size_t buf_size, char *buf)
     H5TRACE3("Zs","izs",attr_id,buf_size,buf);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) ||
-	(NULL == (attr = H5I_object(attr_id)))) {
+    if (NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
     if (!buf || buf_size<1) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid buffer");
     }
@@ -1273,12 +1255,12 @@ H5Aclose(hid_t attr_id)
     H5TRACE1("e","i",attr_id);
 
     /* check arguments */
-    if (H5I_ATTR != H5I_get_type(attr_id) || NULL == H5I_object(attr_id)) {
+    if (NULL == H5I_object_verify(attr_id, H5I_ATTR))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute");
-    }
 
     /* Decrement references to that atom (and close it) */
     H5I_dec_ref (attr_id);
+
     FUNC_LEAVE(SUCCEED);
 } /* H5Aclose() */
 
diff --git a/src/H5AC.c b/src/H5AC.c
index 7b81c8a..bb4b43e 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -102,7 +102,7 @@ H5AC_init_interface(void)
     assert(H5P_CLS_DATASET_XFER_g!=(-1));
 
     /* Get the dataset transfer property list class object */
-    if (H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_DATASET_XFER_g) || NULL == (xfer_pclass = H5I_object(H5P_CLS_DATASET_XFER_g)))
+    if (NULL == (xfer_pclass = H5I_object_verify(H5P_CLS_DATASET_XFER_g, H5I_GENPROP_CLS)))
         HRETURN_ERROR(H5E_CACHE, H5E_BADATOM, FAIL, "can't get property list class");
 
     /* Create a new dataset transfer property list */
diff --git a/src/H5D.c b/src/H5D.c
index 0468091..6d82625 100644
--- a/src/H5D.c
+++ b/src/H5D.c
@@ -193,7 +193,7 @@ H5D_init_interface(void)
     assert(H5P_CLS_DATASET_XFER_g!=(-1));
 
     /* Get the pointer to the dataset transfer class */
-    if (H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_DATASET_XFER_g) || NULL == (xfer_pclass = H5I_object(H5P_CLS_DATASET_XFER_g)))
+    if (NULL == (xfer_pclass = H5I_object_verify(H5P_CLS_DATASET_XFER_g, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
 
     /* Get the number of properties in the class */
@@ -273,7 +273,7 @@ H5D_init_interface(void)
     assert(H5P_CLS_DATASET_CREATE_g != -1);
     
     /* Get the pointer to the dataset creation class */
-    if(H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_DATASET_CREATE_g) || NULL == (crt_pclass = H5I_object(H5P_CLS_DATASET_CREATE_g)))
+    if(NULL == (crt_pclass = H5I_object_verify(H5P_CLS_DATASET_CREATE_g, H5I_GENPROP_CLS)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
         
     /* Get the number of properties in the class */
@@ -692,44 +692,39 @@ H5Dcreate(hid_t loc_id, const char *name, hid_t type_id, hid_t space_id,
     H5T_t		   *type = NULL;
     H5S_t		   *space = NULL;
     H5D_t		   *new_dset = NULL;
-    hid_t		    ret_value = FAIL;
+    hid_t		    ret_value;
 
     FUNC_ENTER_API(H5Dcreate, FAIL);
     H5TRACE5("i","isiii",loc_id,name,type_id,space_id,plist_id);
 
     /* Check arguments */
-    if (NULL == (loc = H5G_loc(loc_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location");
-    }
-    if (!name || !*name) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
-    }
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (type = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a type");
-    }
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-	NULL == (space = H5I_object(space_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
+    if (NULL == (loc = H5G_loc(loc_id)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location");
+    if (!name || !*name)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
+    if (NULL == (type = H5I_object_verify(type_id, H5I_DATATYPE)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a type");
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(H5P_DEFAULT == plist_id)
         plist_id = H5P_DATASET_CREATE_DEFAULT;
-    if(H5I_GENPROP_LST != H5I_get_type(plist_id) ||
-        TRUE != H5P_isa_class(plist_id, H5P_DATASET_CREATE))
-        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, 
-                      "not dataset create property list");
+    if(H5I_GENPROP_LST != H5I_get_type(plist_id) || TRUE != H5P_isa_class(plist_id, H5P_DATASET_CREATE))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not dataset create property list");
 
     /* build and open the new dataset */
-    if (NULL == (new_dset = H5D_create(loc, name, type, space, plist_id))) {
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL,
-		      "unable to create dataset");
-    }
+    if (NULL == (new_dset = H5D_create(loc, name, type, space, plist_id)))
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to create dataset");
+
     /* Register the new dataset to get an ID for it */
-    if ((ret_value = H5I_register(H5I_DATASET, new_dset)) < 0) {
-	H5D_close(new_dset);
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL,
-		      "unable to register dataset");
-    }
+    if ((ret_value = H5I_register(H5I_DATASET, new_dset)) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL, "unable to register dataset");
+
+done:
+    if(ret_value<0) {
+        if(new_dset!=NULL)
+            H5D_close(new_dset);
+    } /* end if */
+
     FUNC_LEAVE(ret_value);
 }
 
@@ -759,33 +754,35 @@ H5Dopen(hid_t loc_id, const char *name)
 {
     H5G_entry_t	*loc = NULL;		/*location holding the dataset	*/
     H5D_t	*dataset = NULL;	/*the dataset			*/
-    hid_t	ret_value = FAIL;
+    hid_t	ret_value;
 
     FUNC_ENTER_API(H5Dopen, FAIL);
     H5TRACE2("i","is",loc_id,name);
 
     /* Check args */
-    if (NULL == (loc = H5G_loc(loc_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location");
-    }
-    if (!name || !*name) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
-    }
+    if (NULL == (loc = H5G_loc(loc_id)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location");
+    if (!name || !*name)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
     
     /* Find the dataset */
-    if (NULL == (dataset = H5D_open(loc, name))) {
-	HRETURN_ERROR(H5E_DATASET, H5E_NOTFOUND, FAIL, "dataset not found");
-    }
+    if (NULL == (dataset = H5D_open(loc, name)))
+	HGOTO_ERROR(H5E_DATASET, H5E_NOTFOUND, FAIL, "dataset not found");
     
     /* Create an atom for the dataset */
-    if ((ret_value = H5I_register(H5I_DATASET, dataset)) < 0) {
-	H5D_close(dataset);
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL,
-		      "can't register dataset");
-    }
+    if ((ret_value = H5I_register(H5I_DATASET, dataset)) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL, "can't register dataset");
+
+done:
+    if(ret_value<0) {
+        if(dataset!=NULL)
+            H5D_close(dataset);
+    } /* end if */
+
     FUNC_LEAVE(ret_value);
 }
 
+
 /*-------------------------------------------------------------------------
  * Function:	H5Dclose
  *
@@ -809,26 +806,29 @@ H5Dopen(hid_t loc_id, const char *name)
 herr_t
 H5Dclose(hid_t dset_id)
 {
-    H5D_t		   *dset = NULL;	/* dataset object to release */
+    H5D_t	*dset = NULL;	        /* Dataset object to release */
+    herr_t       ret_value=SUCCEED;     /* Return value */
 
     FUNC_ENTER_API(H5Dclose, FAIL);
     H5TRACE1("e","i",dset_id);
 
     /* Check args */
-    if (H5I_DATASET != H5I_get_type(dset_id) ||
-	NULL == (dset = H5I_object(dset_id)) ||
-	NULL == dset->ent.file) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
+    if (NULL == (dset = H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL == dset->ent.file)
+	HGOTO_ERROR(H5E_DATASET, H5E_BADTYPE, FAIL, "not a dataset");
+
     /*
      * Decrement the counter on the dataset.  It will be freed if the count
      * reaches zero.
      */
-    if (H5I_dec_ref(dset_id) < 0) {
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't free");
-    }
-    FUNC_LEAVE(SUCCEED);
+    if (H5I_dec_ref(dset_id) < 0)
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "can't free");
+
+done:
+    FUNC_LEAVE(ret_value);
 }
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5Dget_space
@@ -855,29 +855,28 @@ H5Dget_space(hid_t dset_id)
 {
     H5D_t	*dset = NULL;
     H5S_t	*space = NULL;
-    hid_t	ret_value = FAIL;
+    hid_t	ret_value;
     
     FUNC_ENTER_API(H5Dget_space, FAIL);
     H5TRACE1("i","i",dset_id);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type (dset_id) ||
-	NULL==(dset=H5I_object (dset_id))) {
-	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
 
     /* Read the data space message and return a data space object */
-    if (NULL==(space=H5D_get_space (dset))) {
-	HRETURN_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL,
-		       "unable to get data space");
-    }
+    if (NULL==(space=H5D_get_space (dset)))
+	HGOTO_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL, "unable to get data space");
 
     /* Create an atom */
-    if ((ret_value=H5I_register (H5I_DATASPACE, space))<0) {
-	H5S_close(space);
-	HRETURN_ERROR (H5E_ATOM, H5E_CANTREGISTER, FAIL,
-		       "unable to register data space");
-    }
+    if ((ret_value=H5I_register (H5I_DATASPACE, space))<0)
+	HGOTO_ERROR (H5E_ATOM, H5E_CANTREGISTER, FAIL, "unable to register data space");
+
+done:
+    if(ret_value<0) {
+        if(space!=NULL)
+            H5S_close(space);
+    } /* end if */
 
     FUNC_LEAVE (ret_value);
 }
@@ -907,10 +906,8 @@ H5D_get_space(H5D_t *dset)
     FUNC_ENTER_NOAPI(H5D_get_space, NULL);
     assert(dset);
 
-    if (NULL==(space=H5S_read(&(dset->ent)))) {
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, NULL,
-		      "unable to load space info from dataset header");
-    }
+    if (NULL==(space=H5S_read(&(dset->ent))))
+	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to load space info from dataset header");
 
     FUNC_LEAVE(space);
 }
@@ -940,7 +937,7 @@ herr_t H5Dget_space_status(hid_t dset_id, H5D_space_status_t *allocation)
     FUNC_ENTER_API(H5Dget_space_status, FAIL);
 
     /* Check arguments */
-    if(H5I_DATASET != H5I_get_type(dset_id) || NULL==(dset=H5I_object(dset_id)))
+    if(NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
 	HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
 
     /* Read data space address and return */
@@ -1052,32 +1049,30 @@ H5Dget_type(hid_t dset_id)
     H5TRACE1("i","i",dset_id);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type (dset_id) ||
-	NULL==(dset=H5I_object (dset_id))) {
-	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
 
     /* Copy the data type and mark it read-only */
-    if (NULL==(copied_type=H5T_copy (dset->type, H5T_COPY_REOPEN))) {
-	HRETURN_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL,
-		       "unable to copy the data type");
-    }
+    if (NULL==(copied_type=H5T_copy (dset->type, H5T_COPY_REOPEN)))
+	HGOTO_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL, "unable to copy the data type");
+
     /* Mark any VL datatypes as being in memory now */
-	if (H5T_vlen_mark(copied_type, NULL, H5T_VLEN_MEMORY)<0) {
-        HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid VL location");
-    }
-    if (H5T_lock (copied_type, FALSE)<0) {
-	H5T_close (copied_type);
-	HRETURN_ERROR (H5E_DATATYPE, H5E_CANTINIT, FAIL,
-		       "unable to lock transient data type");
-    }
+    if (H5T_vlen_mark(copied_type, NULL, H5T_VLEN_MEMORY)<0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "invalid VL location");
+
+    /* Unlock copied type */
+    if (H5T_lock (copied_type, FALSE)<0)
+	HGOTO_ERROR (H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to lock transient data type");
     
     /* Create an atom */
-    if ((ret_value=H5I_register (H5I_DATATYPE, copied_type))<0) {
-	H5T_close (copied_type);
-	HRETURN_ERROR (H5E_ATOM, H5E_CANTREGISTER, FAIL,
-		       "unable to register data type");
-    }
+    if ((ret_value=H5I_register (H5I_DATATYPE, copied_type))<0)
+	HGOTO_ERROR (H5E_ATOM, H5E_CANTREGISTER, FAIL, "unable to register data type");
+
+done:
+    if(ret_value<0) {
+        if(copied_type!=NULL)
+            H5T_close (copied_type);
+    } /* end if */
 
     FUNC_LEAVE (ret_value);
 }
@@ -1113,35 +1108,45 @@ H5Dget_create_plist(hid_t dset_id)
     H5O_fill_t          copied_fill={NULL,0,NULL};
     H5P_genplist_t      *dcpl_plist;
     H5P_genplist_t      *new_plist;
+    hid_t		new_dcpl_id = FAIL;
     hid_t		ret_value = FAIL;
     
     FUNC_ENTER_API(H5Dget_create_plist, FAIL);
     H5TRACE1("i","i",dset_id);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type (dset_id) || NULL==(dset=H5I_object (dset_id)))
-	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
     if (NULL == (dcpl_plist = H5I_object(dset->dcpl_id)))
-        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
 
     /* Copy the creation property list */
-    if((ret_value = H5P_copy_plist(dcpl_plist)) < 0)
-        HRETURN_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to copy the creation property list");
-    if (NULL == (new_plist = H5I_object(ret_value)))
-        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
+    if((new_dcpl_id = H5P_copy_plist(dcpl_plist)) < 0)
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to copy the creation property list");
+    if (NULL == (new_plist = H5I_object(new_dcpl_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
 
     /* Get the fill value property */
     if(H5P_get(new_plist, H5D_CRT_FILL_VALUE_NAME, &copied_fill) < 0)
-        HRETURN_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get fill value");
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get fill value");
 
     /* Copy the dataset type into the fill value message */
     if(copied_fill.type==NULL)
         if(NULL==(copied_fill.type=H5T_copy(dset->type, H5T_COPY_TRANSIENT)))
-            HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to copy dataset data type for fill value");
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to copy dataset data type for fill value");
 
     /* Set back the fill value property to property list */
     if(H5P_set(new_plist, H5D_CRT_FILL_VALUE_NAME, &copied_fill) < 0)
-        HRETURN_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "unable to set property list fill value");
+        HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "unable to set property list fill value");
+
+    /* Set the return value */
+    ret_value=new_dcpl_id;
+
+done:
+    if(ret_value<0) {
+        if(new_dcpl_id>0)
+            H5Pclose(new_dcpl_id);
+    } /* end if */
 
     FUNC_LEAVE (ret_value);
 }
@@ -1195,59 +1200,51 @@ H5Dread(hid_t dset_id, hid_t mem_type_id, hid_t mem_space_id,
     const H5T_t		   *mem_type = NULL;
     const H5S_t		   *mem_space = NULL;
     const H5S_t		   *file_space = NULL;
+    herr_t                  ret_value=SUCCEED;  /* Return value */
 
     FUNC_ENTER_API(H5Dread, FAIL);
     H5TRACE6("e","iiiiix",dset_id,mem_type_id,mem_space_id,file_space_id,
              plist_id,buf);
 
     /* check arguments */
-    if (H5I_DATASET != H5I_get_type(dset_id) ||
-            NULL == (dset = H5I_object(dset_id)) ||
-            NULL == dset->ent.file) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
-    if (H5I_DATATYPE != H5I_get_type(mem_type_id) ||
-            NULL == (mem_type = H5I_object(mem_type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
+    if (NULL == (dset = H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL == dset->ent.file)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL == (mem_type = H5I_object_verify(mem_type_id, H5I_DATATYPE)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
     if (H5S_ALL != mem_space_id) {
-	if (H5I_DATASPACE != H5I_get_type(mem_space_id) ||
-                NULL == (mem_space = H5I_object(mem_space_id))) {
-	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-	}
+	if (NULL == (mem_space = H5I_object_verify(mem_space_id, H5I_DATASPACE)))
+	    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
+
 	/* Check for valid selection */
-	if((*mem_space->select.is_valid)(mem_space)!=TRUE) {
-	    HRETURN_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL,
-			  "selection+offset not within extent");
-	}
+	if((*mem_space->select.is_valid)(mem_space)!=TRUE)
+	    HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "selection+offset not within extent");
     }
     if (H5S_ALL != file_space_id) {
-	if (H5I_DATASPACE != H5I_get_type(file_space_id) ||
-                NULL == (file_space = H5I_object(file_space_id))) {
-	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-	}
+	if (NULL == (file_space = H5I_object_verify(file_space_id, H5I_DATASPACE)))
+	    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
+
 	/* Check for valid selection */
-	if((*file_space->select.is_valid)(file_space)!=TRUE) {
-	    HRETURN_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL,
-			  "selection+offset not within extent");
-	}
+	if((*file_space->select.is_valid)(file_space)!=TRUE)
+	    HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "selection+offset not within extent");
     }
 
     /* Get the default dataset transfer property list if the user didn't provide one */
     if (H5P_DEFAULT == plist_id)
         plist_id= H5P_DATASET_XFER_DEFAULT;
 
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) ||
-            TRUE!=H5P_isa_class(plist_id,H5P_DATASET_XFER))
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
+    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || TRUE!=H5P_isa_class(plist_id,H5P_DATASET_XFER))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
     if (!buf)
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no output buffer");
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no output buffer");
 
     /* read raw data */
     if (H5D_read(dset, mem_type, mem_space, file_space, plist_id, buf/*out*/) < 0)
-	HRETURN_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "can't read data");
+	HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "can't read data");
 
-    FUNC_LEAVE(SUCCEED);
+done:
+    FUNC_LEAVE(ret_value);
 }
 
 /*-------------------------------------------------------------------------
@@ -1293,60 +1290,53 @@ H5Dwrite(hid_t dset_id, hid_t mem_type_id, hid_t mem_space_id,
     const H5T_t		   *mem_type = NULL;
     const H5S_t		   *mem_space = NULL;
     const H5S_t		   *file_space = NULL;
+    herr_t                  ret_value=SUCCEED;  /* Return value */
 
     FUNC_ENTER_API(H5Dwrite, FAIL);
     H5TRACE6("e","iiiiix",dset_id,mem_type_id,mem_space_id,file_space_id,
              plist_id,buf);
 
     /* check arguments */
-    if (H5I_DATASET != H5I_get_type(dset_id) ||
-            NULL == (dset = H5I_object(dset_id)) ||
-            NULL == dset->ent.file) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
-    if (H5I_DATATYPE != H5I_get_type(mem_type_id) ||
-            NULL == (mem_type = H5I_object(mem_type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
+    if (NULL == (dset = H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL == dset->ent.file)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (NULL == (mem_type = H5I_object_verify(mem_type_id, H5I_DATATYPE)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
     if (H5S_ALL != mem_space_id) {
-	if (H5I_DATASPACE != H5I_get_type(mem_space_id) ||
-                NULL == (mem_space = H5I_object(mem_space_id))) {
-	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-	}
+	if (NULL == (mem_space = H5I_object_verify(mem_space_id, H5I_DATASPACE)))
+	    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
+
 	/* Check for valid selection */
-	if ((*mem_space->select.is_valid)(mem_space)!=TRUE) {
-	    HRETURN_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL,
-			  "selection+offset not within extent");
-	}
+	if ((*mem_space->select.is_valid)(mem_space)!=TRUE)
+	    HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "selection+offset not within extent");
     }
     if (H5S_ALL != file_space_id) {
-	if (H5I_DATASPACE != H5I_get_type(file_space_id) ||
-                NULL == (file_space = H5I_object(file_space_id))) {
-	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-	}
+	if (NULL == (file_space = H5I_object_verify(file_space_id, H5I_DATASPACE)))
+	    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
+
 	/* Check for valid selection */
-	if ((*file_space->select.is_valid)(file_space)!=TRUE) {
-	    HRETURN_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL,
-			  "selection+offset not within extent");
-	}
+	if ((*file_space->select.is_valid)(file_space)!=TRUE)
+	    HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "selection+offset not within extent");
     }
 
     /* Get the default dataset transfer property list if the user didn't provide one */
     if (H5P_DEFAULT == plist_id)
         plist_id= H5P_DATASET_XFER_DEFAULT;
 
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) ||
-            TRUE!=H5P_isa_class(plist_id,H5P_DATASET_XFER))
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
+    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || TRUE!=H5P_isa_class(plist_id,H5P_DATASET_XFER))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
     if (!buf)
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no output buffer");
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no output buffer");
 
     /* write raw data */
     if (H5D_write(dset, mem_type, mem_space, file_space, plist_id, buf) < 0)
-	HRETURN_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "can't write data");
+	HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "can't write data");
 
-    FUNC_LEAVE(SUCCEED);
+done:
+    FUNC_LEAVE(ret_value);
 }
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5Dextend
@@ -1368,26 +1358,23 @@ herr_t
 H5Dextend(hid_t dset_id, const hsize_t *size)
 {
     H5D_t	*dset = NULL;
+    herr_t       ret_value=SUCCEED;  /* Return value */
     
     FUNC_ENTER_API(H5Dextend, FAIL);
     H5TRACE2("e","i*h",dset_id,size);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type(dset_id) ||
-	NULL==(dset=H5I_object(dset_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
-    if (!size) {
-	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "no size specified");
-    }
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if (!size)
+	HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "no size specified");
 
     /* Increase size */
-    if (H5D_extend (dset, size)<0) {
-	HRETURN_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL,
-		       "unable to extend dataset");
-    }
+    if (H5D_extend (dset, size)<0)
+	HGOTO_ERROR (H5E_DATASET, H5E_CANTINIT, FAIL, "unable to extend dataset");
 
-    FUNC_LEAVE (SUCCEED);
+done:
+    FUNC_LEAVE (ret_value);
 }
 
 
@@ -1593,11 +1580,8 @@ H5D_create(H5G_entry_t *loc, const char *name, const H5T_t *type,
              * Also, only the slowest varying dimension of a simple data space
              * can be extendible.
              */
-	    if ((ndims=H5S_get_simple_extent_dims(space, new_dset->layout.dim,
-                                                  max_dim))<0) {
-                HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL,
-                    "unable to initialize contiguous storage");
-            }
+	    if ((ndims=H5S_get_simple_extent_dims(space, new_dset->layout.dim, max_dim))<0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize contiguous storage");
             for (i=1; i<ndims; i++) {
                 if (max_dim[i]>new_dset->layout.dim[i])
                     HGOTO_ERROR (H5E_DATASET, H5E_CANTINIT, NULL, "only the first dimension can be extendible");
@@ -1685,20 +1669,18 @@ H5D_create(H5G_entry_t *loc, const char *name, const H5T_t *type,
    
     if(fill.fill_defined == FALSE && fill_time != H5D_FILL_TIME_NEVER)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT,NULL, "unable to create dataset");
+
     /* Write new fill value message */
-    if (H5O_modify(&(new_dset->ent), H5O_FILL_NEW, 0, H5O_FLAG_CONSTANT, 
-			&fill) < 0)
+    if (H5O_modify(&(new_dset->ent), H5O_FILL_NEW, 0, H5O_FLAG_CONSTANT, &fill) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to update fill value header message");        
-
     H5O_reset(H5O_FILL, &fill_prop);
     if(fill.buf && (NULL==H5O_copy(H5O_FILL, &fill, &fill_prop)))
         HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT,NULL,"unable to copy fill value");
     H5O_reset(H5O_FILL_NEW, &fill);
+
     /* Write old fill value */
-    if (fill_prop.buf && H5O_modify(&(new_dset->ent), H5O_FILL, 0, 
-	H5O_FLAG_CONSTANT, &fill_prop) < 0)        
-	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, 
-			"unable to update fill value header message");
+    if (fill_prop.buf && H5O_modify(&(new_dset->ent), H5O_FILL, 0, H5O_FLAG_CONSTANT, &fill_prop) < 0)        
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to update fill value header message");
     if(H5P_set(new_plist, H5D_CRT_FILL_VALUE_NAME, &fill_prop) < 0)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, NULL, "can't set fill value");  
 
@@ -1740,8 +1722,7 @@ H5D_create(H5G_entry_t *loc, const char *name, const H5T_t *type,
 	new_dset->layout.addr = HADDR_UNDEF;
 #else /*H5_HAVE_PARALLEL*/
     if (0==efl.nused) {
-        if(dcpl_layout==H5D_CHUNKED || (dcpl_layout==H5D_CONTIGUOUS && 
-                space_time==H5D_SPACE_ALLOC_EARLY)) {
+        if(dcpl_layout==H5D_CHUNKED || (dcpl_layout==H5D_CONTIGUOUS && space_time==H5D_SPACE_ALLOC_EARLY)) {
             if (H5F_arr_create(f, &(new_dset->layout))<0)
             	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize storage"); 
         } /* end if */
@@ -1787,8 +1768,7 @@ H5D_create(H5G_entry_t *loc, const char *name, const H5T_t *type,
     if (H5D_init_storage(new_dset, space)<0)
 	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize storage");
 #else /*H5_HAVE_PARALLEL*/
-    if(fill_time==H5D_FILL_TIME_ALLOC &&
-        ((space_time==H5D_SPACE_ALLOC_EARLY && !efl.nused) || (efl.nused)))
+    if(fill_time==H5D_FILL_TIME_ALLOC && ((space_time==H5D_SPACE_ALLOC_EARLY && !efl.nused) || (efl.nused)))
 	if (H5D_init_storage(new_dset, space)<0)
 	    HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize storage");
 #endif /*H5_HAVE_PARALLEL*/
@@ -1805,6 +1785,7 @@ done:
         new_dset->ent.file = NULL;
         H5FL_FREE(H5D_t,new_dset);
     }
+
     FUNC_LEAVE(ret_value);
 }
 
@@ -1832,6 +1813,7 @@ htri_t
 H5D_isa(H5G_entry_t *ent)
 {
     htri_t	exists;
+    htri_t	ret_value=TRUE;         /* Return value */
     
     FUNC_ENTER_NOAPI(H5D_isa, FAIL);
 
@@ -1839,25 +1821,24 @@ H5D_isa(H5G_entry_t *ent)
 
     /* Data type */
     if ((exists=H5O_exists(ent, H5O_DTYPE, 0))<0) {
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL,
-		      "unable to read object header");
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to read object header");
     } else if (!exists) {
 	HRETURN(FALSE);
     }
 
     /* Layout */
     if ((exists=H5O_exists(ent, H5O_LAYOUT, 0))<0) {
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL,
-		      "unable to read object header");
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to read object header");
     } else if (!exists) {
 	HRETURN(FALSE);
     }
     
 
-    
-    FUNC_LEAVE(TRUE);
+done:
+    FUNC_LEAVE(ret_value);
 }
 
+
 /*
  *------------------------------------------------------------------------- 
  * Function:	H5D_open
@@ -1897,13 +1878,12 @@ H5D_open(H5G_entry_t *loc, const char *name)
     assert (name && *name);
     
     /* Find the dataset object */
-    if (H5G_find(loc, name, NULL, &ent) < 0) {
+    if (H5G_find(loc, name, NULL, &ent) < 0)
         HGOTO_ERROR(H5E_DATASET, H5E_NOTFOUND, NULL, "not found");
-    }
+
     /* Open the dataset object */
-    if ((dataset=H5D_open_oid(&ent)) ==NULL) {
+    if ((dataset=H5D_open_oid(&ent)) ==NULL)
         HGOTO_ERROR(H5E_DATASET, H5E_NOTFOUND, NULL, "not found");
-    }
 
     /* Success */
     ret_value = dataset;
@@ -1912,6 +1892,7 @@ done:
     FUNC_LEAVE(ret_value);
 }
 
+
 /*-------------------------------------------------------------------------
  * Function:	H5D_open_oid
  *
@@ -2073,8 +2054,7 @@ H5D_open_oid(H5G_entry_t *ent)
      * This is especially important for parallel I/O where the B-tree must
      * be fully populated before I/O can happen.
      */
-    if ((H5F_get_intent(dataset->ent.file) & H5F_ACC_RDWR) &&
-            H5D_CHUNKED==dataset->layout.type) {
+    if ((H5F_get_intent(dataset->ent.file) & H5F_ACC_RDWR) && H5D_CHUNKED==dataset->layout.type) {
         if (H5D_init_storage(dataset, space)<0)
             HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, NULL, "unable to initialize file storage");
     }
@@ -2096,6 +2076,7 @@ done:
     FUNC_LEAVE(ret_value);
 }
 
+
 /*-------------------------------------------------------------------------
  * Function:	H5D_close
  *
@@ -2260,7 +2241,7 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset creation property list");
 
     /* Get the dataset transfer property list */
-    if (NULL == (dx_plist = H5I_object(dxpl_id)))
+    if (NULL == (dx_plist = H5I_object_verify(dxpl_id,H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset creation property list");
 
     if (!file_space) {
@@ -2674,7 +2655,7 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset creation property list");
 
     /* Get the dataset transfer property list */
-    if (NULL == (dx_plist = H5I_object(dxpl_id)))
+    if (NULL == (dx_plist = H5I_object_verify(dxpl_id,H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset creation property list");
 
 #ifdef H5_HAVE_PARALLEL
@@ -3033,7 +3014,7 @@ done:
 herr_t
 H5D_extend (H5D_t *dataset, const hsize_t *size)
 {
-    herr_t	changed, ret_value=FAIL;
+    herr_t	changed, ret_value=SUCCEED;
     H5S_t	*space = NULL;
     H5O_fill_t  fill;
     H5P_genplist_t *plist;      /* Property list */
@@ -3083,8 +3064,6 @@ H5D_extend (H5D_t *dataset, const hsize_t *size)
 	    HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize dataset with fill value");
     } /* end if */
 
-    ret_value = SUCCEED;
-
 done:
     H5S_close(space);
     FUNC_LEAVE (ret_value);
@@ -3324,11 +3303,11 @@ H5Dget_storage_size(hid_t dset_id)
     H5TRACE1("h","i",dset_id);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type(dset_id) || NULL==(dset=H5I_object(dset_id))) {
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a dataset");
-    }
 
     size = H5D_get_storage_size(dset);
+
     FUNC_LEAVE(size);
 }
 
@@ -3444,24 +3423,24 @@ H5Diterate(void *buf, hid_t type_id, hid_t space_id, H5D_operator_t op,
         void *operator_data)
 {
     H5S_t		   *space = NULL;
-    herr_t ret_value=FAIL;
+    herr_t ret_value;
 
     FUNC_ENTER_API(H5Diterate, FAIL);
     H5TRACE5("e","xiixx",buf,type_id,space_id,op,operator_data);
 
     /* Check args */
     if (NULL==op)
-        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid operator");
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid operator");
     if (buf==NULL)
-        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid buffer");
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid buffer");
     if (H5I_DATATYPE != H5I_get_type(type_id))
-        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid datatype");
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-            NULL == (space = H5I_object(space_id)))
-        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid dataspace");
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid datatype");
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "invalid dataspace");
 
     ret_value=H5S_select_iterate(buf,type_id,space,op,operator_data);
 
+done:
     FUNC_LEAVE(ret_value);
 }   /* end H5Diterate() */
 
@@ -3486,7 +3465,7 @@ H5Diterate(void *buf, hid_t type_id, hid_t space_id, H5D_operator_t op,
 herr_t
 H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t plist_id, void *buf)
 {
-    herr_t ret_value=FAIL;
+    herr_t ret_value;
 
     FUNC_ENTER_API(H5Dvlen_reclaim, FAIL);
     H5TRACE4("e","iiix",type_id,space_id,plist_id,buf);
@@ -3495,21 +3474,23 @@ H5Dvlen_reclaim(hid_t type_id, hid_t space_id, hid_t plist_id, void *buf)
     if (H5I_DATATYPE!=H5I_get_type(type_id) ||
             H5I_DATASPACE!=H5I_get_type(space_id) ||
             buf==NULL)
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid argument");
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid argument");
 
     /* Get the default dataset transfer property list if the user didn't provide one */
     if (H5P_DEFAULT == plist_id)
         plist_id= H5P_DATASET_XFER_DEFAULT;
 
     if (TRUE!=H5P_isa_class(plist_id,H5P_DATASET_XFER))
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not xfer parms");
 
     /* Call H5Diterate with args, etc. */
     ret_value=H5Diterate(buf,type_id,space_id,H5T_vlen_reclaim,&plist_id);
 
+done:
     FUNC_LEAVE(ret_value);
 }   /* end H5Dvlen_reclaim() */
 
+
 /*-------------------------------------------------------------------------
  * Function:	H5D_vlen_get_buf_size_alloc
  *
@@ -3574,7 +3555,7 @@ H5D_vlen_get_buf_size(void UNUSED *elem, hid_t type_id, hsize_t UNUSED ndim, hss
 {
     H5T_vlen_bufsize_t *vlen_bufsize=(H5T_vlen_bufsize_t *)op_data;
     H5T_t	*dt = NULL;
-    herr_t ret_value=FAIL;
+    herr_t ret_value=0;         /* The correct return value, if this function succeeds */
 
     FUNC_ENTER_NOAPI(H5D_vlen_get_buf_size, FAIL);
 
@@ -3597,11 +3578,7 @@ H5D_vlen_get_buf_size(void UNUSED *elem, hid_t type_id, hsize_t UNUSED ndim, hss
     if(H5Dread(vlen_bufsize->dataset_id,type_id,vlen_bufsize->mspace_id,vlen_bufsize->fspace_id,vlen_bufsize->xfer_pid,vlen_bufsize->fl_tbuf)<0)
         HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "can't read point");
 
-    /* Set the correct return value, if we get this far */
-    ret_value=0;
-
 done:
-
     FUNC_LEAVE(ret_value);
 }   /* end H5D_vlen_get_buf_size() */
 
@@ -3836,11 +3813,11 @@ H5Dfill(const void *fill, hid_t fill_type_id, void *buf, hid_t buf_type_id, hid_
     /* Check args */
     if (buf==NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid buffer");
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (space=H5I_object(space_id)))
+    if (NULL == (space=H5I_object_verify(space_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a dataspace");
-    if (H5I_DATATYPE != H5I_get_type(fill_type_id) || NULL == (fill_type=H5I_object(fill_type_id)))
+    if (NULL == (fill_type=H5I_object_verify(fill_type_id, H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a datatype");
-    if (H5I_DATATYPE != H5I_get_type(buf_type_id) || NULL == (buf_type=H5I_object(buf_type_id)))
+    if (NULL == (buf_type=H5I_object_verify(buf_type_id, H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a datatype");
 
     /* Fill the selection in the memory buffer */
@@ -3875,22 +3852,23 @@ herr_t
 H5Dset_extent(hid_t dset_id, const hsize_t *size)
 {
     H5D_t                  *dset = NULL;
+    herr_t                  ret_value=SUCCEED;  /* Return value */
 
     FUNC_ENTER_API(H5Dset_extent, FAIL);
     H5TRACE2("e","i*h",dset_id,size);
 
     /* Check args */
-    if(H5I_DATASET != H5I_get_type(dset_id)
-	    || NULL == (dset = H5I_object(dset_id)))
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
+    if(NULL == (dset = H5I_object_verify(dset_id, H5I_DATASET)))
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
     if(!size)
-	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no size specified");
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no size specified");
 
     /* Private function */
     if(H5D_set_extent(dset, size) < 0)
-	HRETURN_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to set extend dataset");
+	HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to set extend dataset");
 
-    FUNC_LEAVE(SUCCEED);
+done:
+    FUNC_LEAVE(ret_value);
 }
 
 
@@ -3918,7 +3896,7 @@ H5D_set_extent(H5D_t *dset, const hsize_t *size)
 {
     hsize_t                 curr_dims[H5O_LAYOUT_NDIMS];	/* Current dimension sizes */
     int                     rank;	/* Dataspace # of dimensions */
-    herr_t                  ret_value = FAIL;
+    herr_t                  ret_value = SUCCEED;        /* Return value */
     H5S_t                  *space = NULL;
     H5P_genplist_t         *plist;
     int                     u;
@@ -3977,20 +3955,10 @@ H5D_set_extent(H5D_t *dset, const hsize_t *size)
   *-------------------------------------------------------------------------
   */
     if(shrink && H5D_CHUNKED == dset->layout.type) {
-#if defined (PVN)
-	H5F_istore_dump_btree(dset->ent.file, stdout, dset->layout.ndims,
-		dset->layout.addr);
-#endif
-
         /* Remove excess chunks */
 	if(H5F_istore_prune_by_extent(dset->ent.file, &dset->layout, space) < 0)
 	    HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "unable to remove chunks ");
 
-#if defined (PVN)
-	H5F_istore_dump_btree(dset->ent.file, stdout, dset->layout.ndims,
-		dset->layout.addr);
-#endif
-
         /* Get the dataset creation property list */
 	if(NULL == (plist = H5I_object(dset->dcpl_id)))
 	    HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dset creation property list");
@@ -4000,8 +3968,6 @@ H5D_set_extent(H5D_t *dset, const hsize_t *size)
 	    HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "unable to initialize chunks ");
     } /* end if */
 
-    ret_value = SUCCEED;
-
 done:
     if(space)
 	H5S_close(space);
@@ -4035,18 +4001,14 @@ H5Ddebug(hid_t dset_id, unsigned UNUSED flags)
     H5TRACE2("e","iIu",dset_id,flags);
 
     /* Check args */
-    if (H5I_DATASET!=H5I_get_type(dset_id) ||
-	NULL==(dset=H5I_object(dset_id))) {
+    if (NULL==(dset=H5I_object_verify(dset_id, H5I_DATASET)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset");
-    }
 
     /* Print B-tree information */
     if (H5D_CHUNKED==dset->layout.type) {
-	H5F_istore_dump_btree(dset->ent.file, stdout, dset->layout.ndims,
-			      dset->layout.addr);
+	H5F_istore_dump_btree(dset->ent.file, stdout, dset->layout.ndims, dset->layout.addr);
     } else if (H5D_CONTIGUOUS==dset->layout.type) {
-	HDfprintf(stdout, "    %-10s %a\n", "Address:",
-		  dset->layout.addr);
+	HDfprintf(stdout, "    %-10s %a\n", "Address:", dset->layout.addr);
     }
     
     FUNC_LEAVE(SUCCEED);
diff --git a/src/H5E.c b/src/H5E.c
index dcd293d..aa3201e 100644
--- a/src/H5E.c
+++ b/src/H5E.c
@@ -103,9 +103,11 @@ static const H5E_minor_mesg_t H5E_minor_mesg_g[] = {
 
     /* Object atom related errors */
     {H5E_BADATOM, 	"Unable to find atom information (already closed?)"},
+    {H5E_BADGROUP, 	"Unable to find ID group information"},
     {H5E_CANTREGISTER, 	"Unable to register new atom"},
     {H5E_CANTINC,      	"Unable to increment reference count"},
     {H5E_CANTDEC,      	"Unable to decrement reference count"},
+    {H5E_NOIDS,      	"Out of IDs for group"},
 
     /* Cache related errors */
     {H5E_CANTFLUSH, 	"Unable to flush data from cache"},
diff --git a/src/H5Epublic.h b/src/H5Epublic.h
index 3458aa6..d6f1dc8 100644
--- a/src/H5Epublic.h
+++ b/src/H5Epublic.h
@@ -143,9 +143,11 @@ typedef enum H5E_minor_t {
 
     /* Object atom related errors */
     H5E_BADATOM,                /*Can't find atom information                */
+    H5E_BADGROUP,               /*Can't find group information               */
     H5E_CANTREGISTER,           /*Can't register new atom                    */
     H5E_CANTINC,                /*Can't increment reference count            */
     H5E_CANTDEC,                /*Can't decrement reference count            */
+    H5E_NOIDS,                  /*Out of IDs for group                       */
 
     /* Cache related errors */
     H5E_CANTFLUSH,              /*Can't flush object from cache              */
diff --git a/src/H5F.c b/src/H5F.c
index 19e94dc..21683a4 100644
--- a/src/H5F.c
+++ b/src/H5F.c
@@ -240,7 +240,7 @@ H5F_init_interface(void)
     assert(H5P_CLS_FILE_CREATE_g!=-1);
 
     /* Get the pointer to file creation class */
-    if(H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_FILE_CREATE_g) || NULL == (crt_pclass = H5I_object(H5P_CLS_FILE_CREATE_g)))
+    if(NULL == (crt_pclass = H5I_object_verify(H5P_CLS_FILE_CREATE_g, H5I_GENPROP_CLS)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
 
     /* Get the number of properties in the class */
@@ -323,7 +323,7 @@ H5F_init_interface(void)
     assert(H5P_CLS_FILE_ACCESS_g!=-1);
 
     /* Get the pointer to file creation class */
-    if(H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_FILE_ACCESS_g) || NULL == (acs_pclass = H5I_object(H5P_CLS_FILE_ACCESS_g)))
+    if(NULL == (acs_pclass = H5I_object_verify(H5P_CLS_FILE_ACCESS_g, H5I_GENPROP_CLS)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
 
     /* Get the number of properties in the class */
@@ -397,7 +397,7 @@ H5F_init_interface(void)
     assert(H5P_CLS_MOUNT_g!=-1);
 
     /* Get the pointer to file mount class */
-    if(H5I_GENPROP_CLS != H5I_get_type(H5P_CLS_MOUNT_g) || NULL == (mnt_pclass = H5I_object(H5P_CLS_MOUNT_g)))
+    if(NULL == (mnt_pclass = H5I_object_verify(H5P_CLS_MOUNT_g, H5I_GENPROP_CLS)))
          HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
 
     /* Get the number of properties in the class */
@@ -600,9 +600,9 @@ H5F_acs_copy(hid_t new_fapl_id, hid_t old_fapl_id, void UNUSED *copy_data)
 
     FUNC_ENTER_NOAPI(H5F_acs_copy, FAIL);
 
-    if(H5I_GENPROP_LST != H5I_get_type(new_fapl_id) || H5I_GENPROP_LST != H5I_get_type(old_fapl_id))
-        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
-    if(NULL == (new_plist = H5I_object(new_fapl_id)) || NULL == (old_plist = H5I_object(old_fapl_id)))
+    if(NULL == (new_plist = H5I_object_verify(new_fapl_id, H5I_GENPROP_LST)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
+    if(NULL == (old_plist = H5I_object_verify(old_fapl_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list");
 
     /* Get values from old property list */
@@ -780,7 +780,7 @@ H5Fget_create_plist(hid_t file_id)
     H5TRACE1("i","i",file_id);
 
     /* check args */
-    if (H5I_FILE!=H5I_get_type(file_id) || NULL==(file=H5I_object(file_id)))
+    if (NULL==(file=H5I_object_verify(file_id, H5I_FILE)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file");
     if(NULL == (plist = H5I_object(file->shared->fcpl_id)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
@@ -828,7 +828,7 @@ H5Fget_access_plist(hid_t file_id)
     H5TRACE1("i","i",file_id);
 
     /* Check args */
-    if (H5I_FILE!=H5I_get_type(file_id) || NULL==(f=H5I_object(file_id)))
+    if (NULL==(f=H5I_object_verify(file_id, H5I_FILE)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file");
 
     /* Make a copy of the default file access property list */
@@ -905,8 +905,7 @@ H5Fget_obj_count(hid_t file_id, unsigned types, unsigned *obj_id_count)
     FUNC_ENTER_API(H5Fget_obj_counts, FAIL);
     H5TRACE3("e","iIu*Iu",file_id,types,obj_id_count);
 
-    if( file_id != H5F_OBJ_ALL && (H5I_FILE != H5I_get_type(file_id) || 
-        NULL==(f=H5I_object(file_id))) )
+    if( file_id != H5F_OBJ_ALL && (NULL==(f=H5I_object_verify(file_id,H5I_FILE))) )
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file id");
     if( (types&H5F_OBJ_ALL)==0)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not an object type");
@@ -973,8 +972,7 @@ H5Fget_obj_ids(hid_t file_id, unsigned types, hid_t *oid_list)
 
     FUNC_ENTER_API(H5Fget_obj_ids, FAIL);
     H5TRACE3("e","iIu*i",file_id,types,oid_list);
-    if( file_id != H5F_OBJ_ALL && (H5I_FILE != H5I_get_type(file_id) || 
-	NULL==(f=H5I_object(file_id))) )
+    if( file_id != H5F_OBJ_ALL && (NULL==(f=H5I_object_verify(file_id,H5I_FILE))) )
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a file id");
     if( (types&H5F_OBJ_ALL)==0)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not an object type");
@@ -2776,7 +2774,7 @@ H5Fclose(hid_t file_id)
     H5TRACE1("e","i",file_id);
 
     /* Check/fix arguments. */
-    if (H5I_FILE != H5I_get_type(file_id) || NULL==H5I_object(file_id))
+    if (NULL==H5I_object_verify(file_id,H5I_FILE))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file atom");
 
     /*
@@ -3108,7 +3106,7 @@ H5Fmount(hid_t loc_id, const char *name, hid_t child_id, hid_t plist_id)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location");
     if (!name || !*name)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
-    if (H5I_FILE!=H5I_get_type(child_id) || NULL==(child=H5I_object(child_id)))
+    if (NULL==(child=H5I_object_verify(child_id,H5I_FILE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file");
     if(H5P_DEFAULT == plist_id)
         plist_id = H5P_MOUNT_DEFAULT;
@@ -3202,7 +3200,7 @@ H5Freopen(hid_t file_id)
     FUNC_ENTER_API(H5Freopen, FAIL);
     H5TRACE1("i","i",file_id);
 
-    if (H5I_FILE!=H5I_get_type(file_id) || NULL==(old_file=H5I_object(file_id)))
+    if (NULL==(old_file=H5I_object_verify(file_id, H5I_FILE)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file");
 
     /* Get a new "top level" file struct, sharing the same "low level" file struct */
diff --git a/src/H5FD.c b/src/H5FD.c
index fb25da8..49e7789 100644
--- a/src/H5FD.c
+++ b/src/H5FD.c
@@ -267,17 +267,12 @@ H5FDunregister(hid_t driver_id)
     H5TRACE1("e","i",driver_id);
 
     /* Check arguments */
-    if (H5I_VFL!=H5I_get_type(driver_id) ||
-	NULL==H5I_object(driver_id)) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
-		      "not a file driver");
-    }
+    if (NULL==H5I_object_verify(driver_id,H5I_VFL))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file driver");
 
     /* The H5FD_class_t struct will be freed by this function */
-    if (H5I_dec_ref(driver_id)<0) {
-	HRETURN_ERROR(H5E_VFL, H5E_CANTINIT, FAIL,
-		      "unable to unregister file driver");
-    }
+    if (H5I_dec_ref(driver_id)<0)
+	HRETURN_ERROR(H5E_VFL, H5E_CANTINIT, FAIL, "unable to unregister file driver");
 
     FUNC_LEAVE(SUCCEED);
 }
@@ -518,11 +513,10 @@ H5FD_fapl_copy(hid_t driver_id, const void *old_fapl)
     FUNC_ENTER_NOAPI(H5FD_fapl_copy, NULL);
 
     /* Check args */
-    if (H5I_VFL!=H5I_get_type(driver_id) ||
-	NULL==(driver=H5I_object(driver_id))) {
+    if (NULL==(driver=H5I_object_verify(driver_id,H5I_VFL)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a driver ID");
-    }
-    if (!old_fapl) HRETURN(NULL); /*but no error*/
+    if (!old_fapl)
+        HRETURN(NULL); /*but no error*/
 
     /* Allow the driver to copy or do it ourselves */
     if (driver->fapl_copy) {
@@ -563,10 +557,8 @@ H5FD_fapl_free(hid_t driver_id, void *fapl)
     FUNC_ENTER_NOAPI(H5FD_fapl_free, FAIL);
 
     /* Check args */
-    if (H5I_VFL!=H5I_get_type(driver_id) ||
-	NULL==(driver=H5I_object(driver_id))) {
+    if (NULL==(driver=H5I_object_verify(driver_id,H5I_VFL)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a driver ID");
-    }
     
     /* Allow driver to free or do it ourselves */
     if (fapl && driver->fapl_free) {
@@ -611,12 +603,10 @@ H5FD_dxpl_copy(hid_t driver_id, const void *old_dxpl)
     FUNC_ENTER_NOAPI(H5FD_dxpl_copy, NULL);
 
     /* Check args */
-    if (H5I_VFL!=H5I_get_type(driver_id) ||
-	NULL==(driver=H5I_object(driver_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL,
-		      "not a driver ID");
-    }
-    if (!old_dxpl) HRETURN(NULL); /*but no error*/
+    if (NULL==(driver=H5I_object_verify(driver_id,H5I_VFL)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a driver ID");
+    if (!old_dxpl)
+        HRETURN(NULL); /*but no error*/
 
     /* Allow the driver to copy or do it ourselves */
     if (driver->dxpl_copy) {
@@ -657,10 +647,8 @@ H5FD_dxpl_free(hid_t driver_id, void *dxpl)
     FUNC_ENTER_NOAPI(H5FD_dxpl_free, FAIL);
 
     /* Check args */
-    if (H5I_VFL!=H5I_get_type(driver_id) ||
-	NULL==(driver=H5I_object(driver_id))) {
+    if (NULL==(driver=H5I_object_verify(driver_id,H5I_VFL)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a driver ID");
-    }
     
     /* Allow driver to free or do it ourselves */
     if (dxpl && driver->dxpl_free) {
@@ -793,7 +781,7 @@ H5FD_open(const char *name, unsigned flags, hid_t fapl_id, haddr_t maxaddr)
         HRETURN_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get driver ID");
 
     /* Get driver info */
-    if (H5I_VFL!=H5I_get_type(driver_id) || NULL==(driver=H5I_object(driver_id)))
+    if (NULL==(driver=H5I_object_verify(driver_id,H5I_VFL)))
 	HRETURN_ERROR(H5E_VFL, H5E_BADVALUE, NULL, "invalid driver ID in file access property list");
     if (NULL==driver->open)
 	HRETURN_ERROR(H5E_VFL, H5E_UNSUPPORTED, NULL, "file driver has no `open' method");
diff --git a/src/H5I.c b/src/H5I.c
index 3e9ad18..bf85308 100644
--- a/src/H5I.c
+++ b/src/H5I.c
@@ -189,20 +189,17 @@ H5I_init_group(H5I_type_t grp, size_t hash_size, unsigned reserved,
     FUNC_ENTER_NOAPI(H5I_init_group, FAIL);
 
     /* Check arguments */
-    if ((grp <= H5I_BADID || grp >= H5I_NGROUPS) && hash_size > 0) {
-	HGOTO_DONE(FAIL);
-    }
+    if ((grp <= H5I_BADID || grp >= H5I_NGROUPS) && hash_size > 0)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
 #ifdef HASH_SIZE_POWER_2
     if (!POWER_OF_TWO(hash_size) || hash_size == 1)
-	HGOTO_DONE(FAIL);
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid hash size");
 #endif /* HASH_SIZE_POWER_2 */
 
     if (H5I_id_group_list_g[grp] == NULL) {
 	/* Allocate the group information for new group */
-	if (NULL==(grp_ptr = H5MM_calloc(sizeof(H5I_id_group_t)))) {
-	    HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL,
-			 "memory allocation failed");
-	}
+	if (NULL==(grp_ptr = H5MM_calloc(sizeof(H5I_id_group_t))))
+	    HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed");
 	H5I_id_group_list_g[grp] = grp_ptr;
     } else {
 	/* Get the pointer to the existing group */
@@ -218,16 +215,14 @@ H5I_init_group(H5I_type_t grp, size_t hash_size, unsigned reserved,
 	grp_ptr->nextid = reserved;
 	grp_ptr->free_func = free_func;
 	grp_ptr->id_list = H5MM_calloc(hash_size*sizeof(H5I_id_info_t *));
-	if (NULL==grp_ptr->id_list) {
-	    HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL,
-			 "memory allocation failed");
-	}
+	if (NULL==grp_ptr->id_list)
+	    HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed");
     }
     
     /* Increment the count of the times this group has been initialized */
     grp_ptr->count++;
 
-  done:
+done:
     if (ret_value<0) {
 	/* Error condition cleanup */
 	if (grp_ptr != NULL) {
@@ -267,18 +262,15 @@ H5I_nmembers(H5I_type_t grp)
 
     FUNC_ENTER_NOAPI(H5I_nmembers, FAIL);
 
-    if (grp<=H5I_BADID || grp>=H5I_NGROUPS) {
+    if (grp<=H5I_BADID || grp>=H5I_NGROUPS)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
-    }
-    if (NULL==(grp_ptr=H5I_id_group_list_g[grp]) || grp_ptr->count<=0) {
+    if (NULL==(grp_ptr=H5I_id_group_list_g[grp]) || grp_ptr->count<=0)
 	HRETURN(0);
-    }
 
-    for (i=0; i<grp_ptr->hash_size; i++) {
-	for (cur=grp_ptr->id_list[i]; cur; cur=cur->next) {
+    for (i=0; i<grp_ptr->hash_size; i++)
+	for (cur=grp_ptr->id_list[i]; cur; cur=cur->next)
 	    n++;
-	}
-    }
+
     FUNC_LEAVE(n);
 }
 
@@ -325,23 +317,20 @@ H5I_clear_group(H5I_type_t grp, hbool_t force)
 
     FUNC_ENTER_NOAPI(H5I_clear_group, FAIL);
 
-    if (grp <= H5I_BADID || grp >= H5I_NGROUPS) {
-	HGOTO_DONE(FAIL);
-    }
+    if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
     
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-	HGOTO_DONE(FAIL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, FAIL, "invalid group");
 
 #ifdef IDS_ARE_CACHED
     /*
      * Remove atoms from the global atom cache.
      */
     for (i=0; i<ID_CACHE_SIZE; i++) {
-	if (H5I_cache_g[i] && H5I_GROUP(H5I_cache_g[i]->id) == grp) {
+	if (H5I_cache_g[i] && H5I_GROUP(H5I_cache_g[i]->id) == grp)
 	    H5I_cache_g[i] = NULL;
-	}
     }
 #endif /* IDS_ARE_CACHED */
 
@@ -470,14 +459,12 @@ H5I_destroy_group(H5I_type_t grp)
 
     FUNC_ENTER_NOAPI(H5I_destroy_group, FAIL);
 
-    if (grp <= H5I_BADID || grp >= H5I_NGROUPS) {
-        HGOTO_DONE(FAIL);
-    }
+    if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
     
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-        HGOTO_DONE(FAIL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, FAIL, "invalid group");
 
     /*
      * Decrement the number of users of the atomic group.  If this is the
@@ -534,16 +521,13 @@ H5I_register(H5I_type_t grp, void *object)
     FUNC_ENTER_NOAPI(H5I_register, FAIL);
 
     /* Check arguments */
-    if (grp <= H5I_BADID || grp >= H5I_NGROUPS) {
-	HGOTO_DONE(FAIL);
-    }
+    if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-	HGOTO_DONE(FAIL);
-    }
-    if ((id_ptr = H5FL_ALLOC(H5I_id_info_t,0)) == NULL) {
-	HGOTO_DONE(FAIL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, FAIL, "invalid group");
+    if ((id_ptr = H5FL_ALLOC(H5I_id_info_t,0)) == NULL)
+        HGOTO_ERROR(H5E_ATOM, H5E_NOSPACE, FAIL, "memory allocation failed");
 
     /* Create the struct & it's ID */
     new_id = H5I_MAKE(grp, grp_ptr->nextid);
@@ -554,9 +538,8 @@ H5I_register(H5I_type_t grp, void *object)
 
     /* hash bucket already full, prepend to front of chain */
     hash_loc = grp_ptr->nextid % (unsigned) grp_ptr->hash_size;
-    if (grp_ptr->id_list[hash_loc] != NULL) {
+    if (grp_ptr->id_list[hash_loc] != NULL)
 	id_ptr->next = grp_ptr->id_list[hash_loc];
-    }
 
     /* Insert into the group */
     grp_ptr->id_list[hash_loc] = id_ptr;
@@ -586,28 +569,29 @@ H5I_register(H5I_type_t grp, void *object)
 	 */
 	for (i=grp_ptr->reserved; i<ID_MASK; i++) {
 	    /* Handle end of range by wrapping to beginning */
-	    if (grp_ptr->nextid>(unsigned)ID_MASK) {
+	    if (grp_ptr->nextid>(unsigned)ID_MASK)
 		grp_ptr->nextid = grp_ptr->reserved;
-	    }
 
 	    /* new ID to check for */
 	    next_id = H5I_MAKE(grp, grp_ptr->nextid);
 	    hash_loc = H5I_LOC (grp_ptr->nextid, grp_ptr->hash_size);
 	    curr_id = grp_ptr->id_list[hash_loc];
-	    if (curr_id == NULL) break; /* Ha! this is not likely... */
+	    if (curr_id == NULL)
+                break; /* Ha! this is not likely... */
 
 	    while (curr_id) {
-		if (curr_id->id == next_id) break;
+		if (curr_id->id == next_id)
+                    break;
 		curr_id = curr_id->next;
 	    }
-	    if (!curr_id) break; /* must not have found a match */
+	    if (!curr_id)
+                break; /* must not have found a match */
 	    grp_ptr->nextid++;
 	}
 
-	if (i>=(unsigned)ID_MASK) {
+	if (i>=(unsigned)ID_MASK)
 	    /* All the IDs are gone! */
-	    HGOTO_DONE(FAIL);
-	}
+            HGOTO_ERROR(H5E_ATOM, H5E_NOIDS, FAIL, "no IDs available in group");
     }
     ret_value = new_id;
 
@@ -651,6 +635,44 @@ H5I_object(hid_t id)
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5I_object_verify
+ *
+ * Purpose:	Find an object pointer for the specified ID, verifying that
+ *                  its in a particular group.
+ *
+ * Return:	Success:	Non-null object pointer associated with the
+ *				specified ID.
+ *
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		Wednesday, July 31, 2002
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+void * 
+H5I_object_verify(hid_t id, H5I_type_t id_type)
+{
+    H5I_id_info_t	*id_ptr = NULL;		/*ptr to the new atom	*/
+    void		*ret_value = NULL;	/*return value		*/
+
+    FUNC_ENTER_NOAPI(H5I_object_verify, NULL);
+
+    assert(id_type>=H5I_FILE && id_type<H5I_NGROUPS);
+
+    /* Verify that the group of the ID is correct & lookup the ID */
+    if(id_type == H5I_GROUP(id) && NULL!=(id_ptr = H5I_find_id(id))) {
+        /* Get the object pointer to return */
+        ret_value = id_ptr->obj_ptr;
+    } /* end if */
+
+    FUNC_LEAVE(ret_value);
+} /* H5I_object_verify() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5I_get_type
  *
  * Purpose:	Given an object ID return the group (type) to which it
@@ -715,10 +737,8 @@ H5Iget_type(hid_t id)
 
     ret_value = H5I_get_type(id);
 
-    if (ret_value <= H5I_BADID || ret_value >= H5I_NGROUPS ||
-	NULL==H5I_object(id)) {
+    if (ret_value <= H5I_BADID || ret_value >= H5I_NGROUPS || NULL==H5I_object(id))
 	HGOTO_DONE(H5I_BADID);
-    }
 
 done:
     FUNC_LEAVE(ret_value);
@@ -760,16 +780,16 @@ H5I_remove(hid_t id)
     /* Check arguments */
     grp = H5I_GROUP(id);
     if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
-        HGOTO_DONE(NULL);
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, NULL, "invalid group number");
     grp_ptr = H5I_id_group_list_g[grp];
     if (grp_ptr == NULL || grp_ptr->count <= 0)
-        HGOTO_DONE(NULL);
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, NULL, "invalid group");
 
     /* Get the bucket in which the ID is located */
     hash_loc = (unsigned) H5I_LOC(id, grp_ptr->hash_size);
     curr_id = grp_ptr->id_list[hash_loc];
     if (curr_id == NULL)
-        HGOTO_DONE(NULL);
+	HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, NULL, "invalid ID");
 
     last_id = NULL;
     while (curr_id != NULL) {
@@ -799,13 +819,13 @@ H5I_remove(hid_t id)
         H5FL_FREE(H5I_id_info_t,curr_id);
     } else {
         /* couldn't find the ID in the proper place */
-        HGOTO_DONE(NULL);
+	HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, NULL, "invalid ID");
     }
 
     /* Decrement the number of IDs in the group */
     (grp_ptr->ids)--;
 
-  done:
+done:
     FUNC_LEAVE(ret_value);
 }
 
@@ -860,9 +880,8 @@ H5I_dec_ref(hid_t id)
 
     /* Check arguments */
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-	HRETURN(FAIL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "invalid group number");
     
     /* General lookup of the ID */
     if ((id_ptr=H5I_find_id(id))) {
@@ -918,12 +937,15 @@ H5I_inc_ref(hid_t id)
     FUNC_ENTER_NOAPI(H5I_inc_ref, FAIL);
 
     /* Check arguments */
-    if (id<0) HRETURN(FAIL);
+    if (id<0)
+	HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "invalid ID");
     grp_ptr = H5I_id_group_list_g[grp];
-    if (!grp_ptr || grp_ptr->count<=0) HRETURN(FAIL);
+    if (!grp_ptr || grp_ptr->count<=0)
+	HRETURN_ERROR(H5E_ATOM, H5E_BADGROUP, FAIL, "invalid group");
 
     /* General lookup of the ID */
-    if (NULL==(id_ptr=H5I_find_id(id))) HRETURN(FAIL);
+    if (NULL==(id_ptr=H5I_find_id(id)))
+	HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "can't locate ID");
     id_ptr->count++;
 
     FUNC_LEAVE(id_ptr->count);
@@ -966,26 +988,23 @@ H5I_search(H5I_type_t grp, H5I_search_func_t func, const void *key)
     FUNC_ENTER_NOAPI(H5I_search, NULL);
 
     /* Check arguments */
-    if (grp <= H5I_BADID || grp >= H5I_NGROUPS) {
-	HGOTO_DONE(NULL);
-    }
+    if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, NULL, "invalid group number");
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-	HGOTO_DONE(NULL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, NULL, "invalid group");
 
     /* Start at the beginning of the array */
     for (i=0; i<grp_ptr->hash_size; i++) {
 	id_ptr = grp_ptr->id_list[i];
 	while (id_ptr) {
-	    if ((*func)(id_ptr->obj_ptr, id_ptr->id, key)) {
+	    if ((*func)(id_ptr->obj_ptr, id_ptr->id, key))
 		HGOTO_DONE(id_ptr->obj_ptr);	/*found the item*/
-	    }
 	    id_ptr = id_ptr->next;
 	}
     }
 
-  done:
+done:
     FUNC_LEAVE(ret_value);
 }
 
@@ -1022,13 +1041,11 @@ H5I_find_id(hid_t id)
 
     /* Check arguments */
     grp = H5I_GROUP(id);
-    if (grp <= H5I_BADID || grp >= H5I_NGROUPS) {
-	HGOTO_DONE(NULL);
-    }
+    if (grp <= H5I_BADID || grp >= H5I_NGROUPS)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, NULL, "invalid group number");
     grp_ptr = H5I_id_group_list_g[grp];
-    if (grp_ptr == NULL || grp_ptr->count <= 0) {
-	HGOTO_DONE(NULL);
-    }
+    if (grp_ptr == NULL || grp_ptr->count <= 0)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADGROUP, NULL, "invalid group");
 
 #ifdef IDS_ARE_CACHED
     /*
@@ -1057,13 +1074,13 @@ H5I_find_id(hid_t id)
     /* Get the bucket in which the ID is located */
     hash_loc = (unsigned)H5I_LOC(id, grp_ptr->hash_size);
     id_ptr = grp_ptr->id_list[hash_loc];
-    if (id_ptr == NULL) {
-	HGOTO_DONE(NULL);
-    }
+    if (id_ptr == NULL)
+	HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, NULL, "invalid ID");
 
     /* Scan the bucket's linked list for a match */
     while (id_ptr) {
-	if (id_ptr->id == id) break;
+	if (id_ptr->id == id)
+            break;
 	id_ptr = id_ptr->next;
     }
     ret_value = id_ptr;
@@ -1073,7 +1090,7 @@ H5I_find_id(hid_t id)
     H5I_cache_g[ID_CACHE_SIZE-1] = id_ptr;
 #endif /* IDS_ARE_CACHED */
 
-  done:
+done:
     FUNC_LEAVE(ret_value);
 }
 
diff --git a/src/H5Iprivate.h b/src/H5Iprivate.h
index a928590..0589cc6 100644
--- a/src/H5Iprivate.h
+++ b/src/H5Iprivate.h
@@ -130,6 +130,7 @@ __DLL__ herr_t H5I_clear_group(H5I_type_t grp, hbool_t force);
 __DLL__ herr_t H5I_destroy_group(H5I_type_t grp);
 __DLL__ hid_t H5I_register(H5I_type_t grp, void *object);
 __DLL__ void *H5I_object(hid_t id);
+__DLL__ void *H5I_object_verify(hid_t id, H5I_type_t id_type);
 __DLL__ H5I_type_t H5I_get_type(hid_t id);
 __DLL__ void *H5I_remove(hid_t id);
 __DLL__ void *H5I_search(H5I_type_t grp, H5I_search_func_t func,
diff --git a/src/H5P.c b/src/H5P.c
index 5476089..eb19ad3 100644
--- a/src/H5P.c
+++ b/src/H5P.c
@@ -29,6 +29,7 @@
 /* Default file driver - see H5Pget_driver() */
 #include "H5FDsec2.h"		/* Posix unbuffered I/O	file driver	*/
 
+/* Pablo mask */
 #define PABLO_MASK	H5P_mask
 
 /* Is the interface initialized? */
@@ -1809,7 +1810,7 @@ H5P_set_driver(H5P_genplist_t *plist, hid_t new_driver_id, const void *new_drive
     
     FUNC_ENTER_NOAPI(H5P_set_driver, FAIL);
 
-    if (H5I_VFL!=H5I_get_type(new_driver_id) || NULL==H5I_object(new_driver_id))
+    if (NULL==H5I_object_verify(new_driver_id, H5I_VFL))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file driver ID");
 
     if( TRUE == H5P_isa_class(plist->plist_id, H5P_FILE_ACCESS) ) {
@@ -1911,9 +1912,9 @@ H5Pset_driver(hid_t plist_id, hid_t new_driver_id, const void *new_driver_info)
     H5TRACE3("e","iix",plist_id,new_driver_id,new_driver_info);
 
     /* Check arguments */
-    if(H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if(NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
-    if (H5I_VFL!=H5I_get_type(new_driver_id) || NULL==H5I_object(new_driver_id))
+    if (NULL==H5I_object_verify(new_driver_id, H5I_VFL))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a file driver ID");
 
     /* Set the driver */
@@ -2021,7 +2022,7 @@ H5Pget_driver(hid_t plist_id)
     FUNC_ENTER_API(H5Pget_driver, FAIL);
     H5TRACE1("i","i",plist_id);
 
-    if(H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if(NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
 
     ret_value = H5P_get_driver(plist);
@@ -2113,7 +2114,7 @@ H5Pget_driver_info(hid_t plist_id)
 
     FUNC_ENTER_API(H5Pget_driver_info, NULL);
 
-    if(H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if(NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a property list");
 
     if((ret_value=H5P_get_driver_info(plist))==NULL)
@@ -3265,8 +3266,7 @@ H5Pset_fill_value(hid_t plist_id, hid_t type_id, const void *value)
         HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't reset fill value");
 
     if(value) {
-	if (H5I_DATATYPE!=H5I_get_type(type_id) || 
-	    NULL==(type=H5I_object(type_id)))
+	if (NULL==(type=H5I_object_verify(type_id, H5I_DATATYPE)))
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
 
 	/* Set the fill value */
@@ -3332,7 +3332,7 @@ H5Pget_fill_value(hid_t plist_id, hid_t type_id, void *value/*out*/)
     /* Check arguments */
     if(TRUE != H5P_isa_class(plist_id, H5P_DATASET_CREATE))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset creation proprety list");
-    if (H5I_DATATYPE!=H5I_get_type(type_id) || NULL==(type=H5I_object(type_id)))
+    if (NULL==(type=H5I_object_verify(type_id, H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
     if (!value)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,"no fill value output buffer");
@@ -5358,7 +5358,7 @@ hid_t H5Pcreate(hid_t cls_id)
     FUNC_ENTER_API(H5Pcreate, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_CLS != H5I_get_type(cls_id) || NULL == (pclass = H5I_object(cls_id)))
+    if (NULL == (pclass = H5I_object_verify(cls_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
 
     /* Create the new property list */
@@ -5725,7 +5725,7 @@ herr_t H5Pregister(hid_t cls_id, const char *name, size_t size, void *def_value,
     FUNC_ENTER_API(H5Pregister, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_CLS != H5I_get_type(cls_id) || NULL == (pclass = H5I_object(cls_id)))
+    if (NULL == (pclass = H5I_object_verify(cls_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid class name");
@@ -6012,7 +6012,7 @@ herr_t H5Pinsert(hid_t plist_id, const char *name, size_t size, void *value,
     FUNC_ENTER_API(H5Pinsert, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid property name");
@@ -6148,7 +6148,7 @@ herr_t H5Pset(hid_t plist_id, const char *name, void *value)
     FUNC_ENTER_API(H5Pset, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid property name");
@@ -6524,7 +6524,7 @@ hid_t H5Pget_class(hid_t plist_id)
     FUNC_ENTER_API(H5Pget_class, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
 
     /* Retrieve the property list class */
@@ -7096,9 +7096,9 @@ htri_t H5P_isa_class(hid_t plist_id, hid_t pclass_id)
     FUNC_ENTER_NOAPI(H5P_isa_class, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
-    if (H5I_GENPROP_CLS != H5I_get_type(pclass_id) || NULL == (pclass = H5I_object(pclass_id)))
+    if (NULL == (pclass = H5I_object_verify(pclass_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property class");
 
     /* Compare the property list's class against the other class */
@@ -7311,7 +7311,7 @@ H5P_iterate_plist(hid_t plist_id, int *idx, H5P_iterate_t iter_func, void *iter_
     assert(iter_func);
 
     /* Get the property list object */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
 
     /* Iterate through the properties in the property list */
@@ -7385,7 +7385,7 @@ H5P_iterate_pclass(hid_t pclass_id, int *idx, H5P_iterate_t iter_func, void *ite
     assert(iter_func);
 
     /* Get the property list object */
-    if (H5I_GENPROP_CLS != H5I_get_type(pclass_id) || NULL == (pclass = H5I_object(pclass_id)))
+    if (NULL == (pclass = H5I_object_verify(pclass_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property class");
 
     /* Iterate through the properties in the property list */
@@ -7809,7 +7809,7 @@ herr_t H5Pget(hid_t plist_id, const char *name, void * value)
     FUNC_ENTER_API(H5Pget, FAIL);
 
     /* Check arguments. */
-    if(H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if(NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid property name");
@@ -7954,7 +7954,7 @@ herr_t H5Premove(hid_t plist_id, const char *name)
     FUNC_ENTER_API(H5Premove, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid property name");
@@ -8327,7 +8327,7 @@ herr_t H5Punregister(hid_t pclass_id, const char *name)
     FUNC_ENTER_API(H5Punregister, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_CLS != H5I_get_type(pclass_id) || NULL == (pclass = H5I_object(pclass_id)))
+    if (NULL == (pclass = H5I_object_verify(pclass_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list class");
     if (!name || !*name)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid property name");
@@ -8428,7 +8428,7 @@ herr_t H5Pclose(hid_t plist_id)
         HGOTO_DONE(SUCCEED);
 
     /* Check arguments. */
-    if (H5I_GENPROP_LST != H5I_get_type(plist_id) || NULL == (plist = H5I_object(plist_id)))
+    if (NULL == (plist = H5I_object_verify(plist_id, H5I_GENPROP_LST)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
 
     /* Close the property list */
@@ -8507,7 +8507,7 @@ char *H5Pget_class_name(hid_t pclass_id)
     FUNC_ENTER_API(H5Pget_class_name, NULL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_CLS != H5I_get_type(pclass_id) || NULL == (pclass = H5I_object(pclass_id)))
+    if (NULL == (pclass = H5I_object_verify(pclass_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a property class");
 
     /* Get the property list class name */
@@ -8582,7 +8582,7 @@ hid_t H5Pget_class_parent(hid_t pclass_id)
     FUNC_ENTER_API(H5Pget_class_parent, FAIL);
 
     /* Check arguments. */
-    if (H5I_GENPROP_CLS != H5I_get_type(pclass_id) || NULL == (pclass = H5I_object(pclass_id)))
+    if (NULL == (pclass = H5I_object_verify(pclass_id, H5I_GENPROP_CLS)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property class");
 
     /* Retrieve the property class's parent */
diff --git a/src/H5R.c b/src/H5R.c
index 722496e..9d4f27f 100644
--- a/src/H5R.c
+++ b/src/H5R.c
@@ -299,7 +299,7 @@ H5Rcreate(void *ref, hid_t loc_id, const char *name, H5R_type_t ref_type, hid_t
         HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "invalid reference type");
     if(ref_type!=H5R_OBJECT && ref_type!=H5R_DATASET_REGION)
         HRETURN_ERROR (H5E_ARGS, H5E_UNSUPPORTED, FAIL, "reference type not supported");
-    if (space_id!=(-1) && (H5I_DATASPACE!=H5I_get_type (space_id) || NULL==(space=H5I_object (space_id))))
+    if (space_id!=(-1) && (NULL==(space=H5I_object_verify(space_id,H5I_DATASPACE))))
         HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace");
 
     /* Create reference */
diff --git a/src/H5S.c b/src/H5S.c
index 49182b0..11403ac 100644
--- a/src/H5S.c
+++ b/src/H5S.c
@@ -469,7 +469,7 @@ H5Sclose(hid_t space_id)
     H5TRACE1("e","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == H5I_object(space_id))
+    if (NULL == H5I_object_verify(space_id,H5I_DATASPACE))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     /* When the reference count reaches zero the resources are freed */
@@ -540,7 +540,7 @@ H5Scopy(hid_t space_id)
     H5TRACE1("i","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE!=H5I_get_type (space_id) || NULL==(src=H5I_object (space_id)))
+    if (NULL==(src=H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     /* Copy */
@@ -580,9 +580,9 @@ H5Sextent_copy(hid_t dst_id,hid_t src_id)
     H5TRACE2("e","ii",dst_id,src_id);
 
     /* Check args */
-    if (H5I_DATASPACE!=H5I_get_type (src_id) || NULL==(src=H5I_object (src_id)))
+    if (NULL==(src=H5I_object_verify(src_id, H5I_DATASPACE)))
         HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    if (H5I_DATASPACE!=H5I_get_type (dst_id) || NULL==(dst=H5I_object (dst_id)))
+    if (NULL==(dst=H5I_object_verify(dst_id, H5I_DATASPACE)))
         HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     /* Copy */
@@ -767,7 +767,7 @@ H5Sget_simple_extent_npoints(hid_t space_id)
     H5TRACE1("Hs","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (ds = H5I_object(space_id)))
+    if (NULL == (ds = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, -1, "not a data space");
 
     ret_value = H5S_get_simple_extent_npoints(ds);
@@ -868,7 +868,7 @@ H5Sget_simple_extent_ndims(hid_t space_id)
     H5TRACE1("Is","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (ds = H5I_object(space_id)))
+    if (NULL == (ds = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     ret_value = H5S_get_simple_extent_ndims(ds);
@@ -960,7 +960,7 @@ H5Sget_simple_extent_dims(hid_t space_id, hsize_t dims[]/*out*/,
     H5TRACE3("Is","ixx",space_id,dims,maxdims);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (ds = H5I_object(space_id)))
+    if (NULL == (ds = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace");
 
     ret_value = H5S_get_simple_extent_dims(ds, dims, maxdims);
@@ -1258,7 +1258,7 @@ H5Sis_simple(hid_t space_id)
     H5TRACE1("b","i",space_id);
 
     /* Check args and all the boring stuff. */
-    if ((space = H5I_object(space_id)) == NULL)
+    if ((space = H5I_object_verify(space_id,H5I_DATASPACE)) == NULL)
 	HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "not a data space");
 
     ret_value = H5S_is_simple(space);
@@ -1304,7 +1304,7 @@ H5Sset_extent_simple(hid_t space_id, int rank, const hsize_t dims[/*rank*/],
     H5TRACE4("e","iIs*[a1]h*[a1]h",space_id,rank,dims,max);
 
     /* Check args */
-    if ((space = H5I_object(space_id)) == NULL)
+    if ((space = H5I_object_verify(space_id,H5I_DATASPACE)) == NULL)
         HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "not a data space");
     if (rank > 0 && dims == NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no dimensions specified");
@@ -1733,7 +1733,7 @@ H5Sget_simple_extent_type(hid_t sid)
     H5TRACE1("Sc","i",sid);
 
     /* Check arguments */
-    if (H5I_DATASPACE != H5I_get_type(sid) || NULL == (space = H5I_object(sid)))
+    if (NULL == (space = H5I_object_verify(sid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5S_NO_CLASS, "not a dataspace");
 
     ret_value=H5S_get_simple_extent_type(space);
@@ -1765,7 +1765,7 @@ H5Sset_extent_none(hid_t space_id)
     H5TRACE1("e","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (space = H5I_object(space_id)))
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "not a data space");
 
     /* Clear the previous extent from the dataspace */
@@ -1803,7 +1803,7 @@ H5Soffset_simple(hid_t space_id, const hssize_t *offset)
     H5TRACE2("e","i*Hs",space_id,offset);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (space = H5I_object(space_id)))
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "not a data space");
     if (offset == NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no offset specified");
diff --git a/src/H5Sall.c b/src/H5Sall.c
index 16686e2..0d30339 100644
--- a/src/H5Sall.c
+++ b/src/H5Sall.c
@@ -543,7 +543,7 @@ herr_t H5Sselect_all (hid_t spaceid)
     FUNC_ENTER_API(H5Sselect_all, FAIL);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     /* Call internal routine to do the work */
diff --git a/src/H5Shyper.c b/src/H5Shyper.c
index 4be5952..64bf457 100644
--- a/src/H5Shyper.c
+++ b/src/H5Shyper.c
@@ -1315,7 +1315,7 @@ H5Sget_select_hyper_nblocks(hid_t spaceid)
     H5TRACE1("Hs","i",spaceid);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(space->select.type!=H5S_SEL_HYPERSLABS)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a hyperslab selection");
@@ -1999,7 +1999,7 @@ H5Sget_select_hyper_blocklist(hid_t spaceid, hsize_t startblock, hsize_t numbloc
     /* Check args */
     if(buf==NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid pointer");
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(space->select.type!=H5S_SEL_HYPERSLABS)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a hyperslab selection");
@@ -4186,10 +4186,8 @@ H5Sselect_hyperslab(hid_t space_id, H5S_seloper_t op, const hssize_t start[],
     H5TRACE6("e","iSs*Hs*h*h*h",space_id,op,start,stride,count,block);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-            NULL == (space=H5I_object(space_id))) {
+    if (NULL == (space=H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
     if(start==NULL || count==NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "hyperslab not specified");
 
@@ -4726,10 +4724,8 @@ H5Sselect_hyperslab(hid_t space_id, H5S_seloper_t op, const hssize_t start[],
     H5TRACE6("e","iSs*Hs*h*h*h",space_id,op,start,stride,count,block);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-            NULL == (space=H5I_object(space_id))) {
+    if (NULL == (space=H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
     if(start==NULL || count==NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "hyperslab not specified");
 
@@ -4784,10 +4780,8 @@ H5Scombine_hyperslab(hid_t space_id, H5S_seloper_t op, const hssize_t start[],
     H5TRACE6("i","iSs*Hs*h*h*h",space_id,op,start,stride,count,block);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) ||
-            NULL == (space=H5I_object(space_id))) {
+    if (NULL == (space=H5I_object_verify(space_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
     if(start==NULL || count==NULL)
         HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "hyperslab not specified");
 
@@ -4894,14 +4888,10 @@ H5Scombine_select(hid_t space1_id, H5S_seloper_t op, hid_t space2_id)
     H5TRACE3("i","iSsi",space1_id,op,space2_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space1_id) ||
-            NULL == (space1=H5I_object(space1_id))) {
+    if (NULL == (space1=H5I_object_verify(space1_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
-    if (H5I_DATASPACE != H5I_get_type(space2_id) ||
-            NULL == (space2=H5I_object(space2_id))) {
+    if (NULL == (space2=H5I_object_verify(space2_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
     if(!(op>H5S_SELECT_NOOP && op<H5S_SELECT_INVALID))
         HGOTO_ERROR(H5E_ARGS, H5E_UNSUPPORTED, FAIL, "invalid selection operation");
 
@@ -5008,14 +4998,10 @@ H5Sselect_select(hid_t space1_id, H5S_seloper_t op, hid_t space2_id)
     H5TRACE3("e","iSsi",space1_id,op,space2_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space1_id) ||
-            NULL == (space1=H5I_object(space1_id))) {
+    if (NULL == (space1=H5I_object_verify(space1_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
-    if (H5I_DATASPACE != H5I_get_type(space2_id) ||
-            NULL == (space2=H5I_object(space2_id))) {
+    if (NULL == (space2=H5I_object_verify(space2_id, H5I_DATASPACE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
-    }
     if(!(op>H5S_SELECT_NOOP && op<H5S_SELECT_INVALID))
         HGOTO_ERROR(H5E_ARGS, H5E_UNSUPPORTED, FAIL, "invalid selection operation");
 
diff --git a/src/H5Snone.c b/src/H5Snone.c
index eee07bd..f9abe49 100644
--- a/src/H5Snone.c
+++ b/src/H5Snone.c
@@ -517,7 +517,7 @@ herr_t H5Sselect_none (hid_t spaceid)
     FUNC_ENTER_API(H5Sselect_none, FAIL);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     /* Change to "none" selection */
diff --git a/src/H5Spoint.c b/src/H5Spoint.c
index 780ba75..c8e25cd 100644
--- a/src/H5Spoint.c
+++ b/src/H5Spoint.c
@@ -541,7 +541,7 @@ H5Sget_select_elem_npoints(hid_t spaceid)
     H5TRACE1("Hs","i",spaceid);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(space->select.type!=H5S_SEL_POINTS)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an element selection");
@@ -839,7 +839,7 @@ H5Sget_select_elem_pointlist(hid_t spaceid, hsize_t startpoint, hsize_t numpoint
     /* Check args */
     if(buf==NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid pointer");
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(space->select.type!=H5S_SEL_POINTS)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a point selection");
@@ -1073,7 +1073,7 @@ H5Sselect_elements (hid_t spaceid, H5S_seloper_t op, size_t num_elem,
     FUNC_ENTER_API(H5Sselect_elements, FAIL);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
     if(coord==NULL || num_elem==0)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "elements not specified");
diff --git a/src/H5Sselect.c b/src/H5Sselect.c
index b37c2b6..18b5ca7 100644
--- a/src/H5Sselect.c
+++ b/src/H5Sselect.c
@@ -148,7 +148,7 @@ H5Sget_select_npoints(hid_t spaceid)
     H5TRACE1("Hs","i",spaceid);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a data space");
 
     ret_value = (*space->select.get_npoints)(space);
@@ -187,7 +187,7 @@ H5Sselect_valid(hid_t spaceid)
     H5TRACE1("b","i",spaceid);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a data space");
 
     ret_value = (*space->select.is_valid)(space);
@@ -295,7 +295,7 @@ H5Sget_select_bounds(hid_t spaceid, hsize_t *start, hsize_t *end)
     /* Check args */
     if(start==NULL || end==NULL)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid pointer");
-    if (H5I_DATASPACE != H5I_get_type(spaceid) || NULL == (space=H5I_object(spaceid)))
+    if (NULL == (space=H5I_object_verify(spaceid, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data space");
 
     ret_value = (*space->select.bounds)(space,start,end);
@@ -381,7 +381,7 @@ H5S_select_iterate(void *buf, hid_t type_id, H5S_t *space, H5D_operator_t op,
         HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate I/O offset vector array");
 
     /* Get the datatype size */
-    if (NULL==(dt=H5I_object(type_id)))
+    if (NULL==(dt=H5I_object_verify(type_id,H5I_DATATYPE)))
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an valid base datatype");
     if((elmt_size=H5T_get_size(dt))==0)
         HGOTO_ERROR(H5E_DATATYPE, H5E_BADSIZE, FAIL, "datatype size invalid");
@@ -496,7 +496,7 @@ H5Sget_select_type(hid_t space_id)
     H5TRACE1("St","i",space_id);
 
     /* Check args */
-    if (H5I_DATASPACE != H5I_get_type(space_id) || NULL == (space = H5I_object(space_id)))
+    if (NULL == (space = H5I_object_verify(space_id, H5I_DATASPACE)))
         HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, H5S_SEL_ERROR, "not a data space");
 
     FUNC_LEAVE(space->select.type);
diff --git a/src/H5T.c b/src/H5T.c
index e25d758..449508b 100644
--- a/src/H5T.c
+++ b/src/H5T.c
@@ -2238,10 +2238,8 @@ H5Tcommit(hid_t loc_id, const char *name, hid_t type_id)
     if (!name || !*name) {
 	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "no name");
     }
-    if (H5I_DATATYPE!=H5I_get_type (type_id) ||
-	NULL==(type=H5I_object (type_id))) {
+    if (NULL==(type=H5I_object_verify(type_id, H5I_DATATYPE)))
 	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
 
     /* Commit the type */
     if (H5T_commit (loc, name, type)<0) {
@@ -2278,10 +2276,8 @@ H5Tcommitted(hid_t type_id)
     H5TRACE1("b","i",type_id);
 
     /* Check arguments */
-    if (H5I_DATATYPE!=H5I_get_type (type_id) ||
-	NULL==(type=H5I_object (type_id))) {
+    if (NULL==(type=H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
 
     FUNC_LEAVE (H5T_STATE_OPEN==type->state || H5T_STATE_NAMED==type->state);
 }
@@ -2378,10 +2374,8 @@ H5Tclose(hid_t type_id)
     H5TRACE1("e","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_IMMUTABLE==dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "immutable data type");
     }
@@ -2424,12 +2418,10 @@ H5Tequal(hid_t type1_id, hid_t type2_id)
     H5TRACE2("b","ii",type1_id,type2_id);
 
     /* check args */
-    if (H5I_DATATYPE != H5I_get_type(type1_id) ||
-	NULL == (dt1 = H5I_object(type1_id)) ||
-	H5I_DATATYPE != H5I_get_type(type2_id) ||
-	NULL == (dt2 = H5I_object(type2_id))) {
+    if (NULL == (dt1 = H5I_object_verify(type1_id,H5I_DATATYPE)) ||
+            NULL == (dt2 = H5I_object_verify(type2_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
+
     ret_value = (0 == H5T_cmp(dt1, dt2)) ? TRUE : FALSE;
 
     FUNC_LEAVE(ret_value);
@@ -2469,10 +2461,8 @@ H5Tlock(hid_t type_id)
     H5TRACE1("e","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_NAMED==dt->state || H5T_STATE_OPEN==dt->state) {
 	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
 		       "unable to lock named data type");
@@ -2512,10 +2502,8 @@ H5Tget_class(hid_t type_id)
     H5TRACE1("Tt","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NO_CLASS, "not a data type");
-    }
     
     FUNC_LEAVE(H5T_get_class(dt));
 }
@@ -2582,10 +2570,8 @@ H5Tdetect_class(hid_t type, H5T_class_t cls)
     H5TRACE2("b","iTt",type,cls);
     
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type) ||
-            NULL == (dt = H5I_object(type))) {
+    if (NULL == (dt = H5I_object_verify(type,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NO_CLASS, "not a data type");
-    }
     if (!(cls>H5T_NO_CLASS && cls<H5T_NCLASSES)) {
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NO_CLASS, "not a data type class");
     }
@@ -2678,7 +2664,7 @@ H5Tget_size(hid_t type_id)
     H5TRACE1("z","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) || NULL == (dt = H5I_object(type_id)))
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a data type");
     
     /* size */
@@ -2725,10 +2711,8 @@ H5Tset_size(hid_t type_id, size_t size)
     H5TRACE2("e","iz",type_id,size);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -2785,12 +2769,11 @@ H5Tget_order(hid_t type_id)
     H5TRACE1("To","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_ORDER_ERROR,
-		      "not a data type");
-    }
-    if (dt->parent) dt = dt->parent; /*defer to parent*/
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_ORDER_ERROR, "not a data type");
+
+    if (dt->parent)
+        dt = dt->parent; /*defer to parent*/
     if (H5T_COMPOUND==dt->type || H5T_OPAQUE==dt->type || H5T_ARRAY ==dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_ORDER_ERROR,
 		      "operation not defined for specified data type");
@@ -2829,10 +2812,8 @@ H5Tset_order(hid_t type_id, H5T_order_t order)
     H5TRACE2("e","iTo",type_id,order);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -2888,10 +2869,8 @@ H5Tget_precision(hid_t type_id)
     H5TRACE1("z","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a data type");
-    }
     if (dt->parent) dt = dt->parent;	/*defer to parent*/
     if (H5T_COMPOUND==dt->type || H5T_OPAQUE==dt->type || H5T_ARRAY==dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, 0,
@@ -2944,10 +2923,8 @@ H5Tset_precision(hid_t type_id, size_t prec)
     H5TRACE2("e","iz",type_id,prec);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3014,10 +2991,8 @@ H5Tget_offset(hid_t type_id)
     H5TRACE1("Is","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an atomic data type");
-    }
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_COMPOUND==dt->type || H5T_OPAQUE==dt->type || H5T_ARRAY==dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
@@ -3080,10 +3055,8 @@ H5Tset_offset(hid_t type_id, size_t offset)
     H5TRACE2("e","iz",type_id,offset);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an atomic data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3133,10 +3106,8 @@ H5Tget_pad(hid_t type_id, H5T_pad_t *lsb/*out*/, H5T_pad_t *msb/*out*/)
     H5TRACE3("e","ixx",type_id,lsb,msb);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_COMPOUND==dt->type || H5T_OPAQUE==dt->type || H5T_ARRAY==dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
@@ -3177,10 +3148,8 @@ H5Tset_pad(hid_t type_id, H5T_pad_t lsb, H5T_pad_t msb)
     H5TRACE3("e","iTpTp",type_id,lsb,msb);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3233,11 +3202,8 @@ H5Tget_sign(hid_t type_id)
     H5TRACE1("Ts","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_SGN_ERROR,
-		      "not an integer data type");
-    }
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_SGN_ERROR, "not an integer data type");
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_INTEGER!=dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_SGN_ERROR,
@@ -3276,10 +3242,8 @@ H5Tset_sign(hid_t type_id, H5T_sign_t sign)
     H5TRACE2("e","iTs",type_id,sign);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an integer data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3336,11 +3300,10 @@ H5Tget_fields(hid_t type_id, size_t *spos/*out*/,
     H5TRACE6("e","ixxxxx",type_id,spos,epos,esize,mpos,msize);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
-    if (dt->parent) dt = dt->parent; /*defer to parent*/
+    if (dt->parent)
+        dt = dt->parent; /*defer to parent*/
     if (H5T_FLOAT != dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
 		      "operation not defined for data type class");
@@ -3389,10 +3352,8 @@ H5Tset_fields(hid_t type_id, size_t spos, size_t epos, size_t esize,
     H5TRACE6("e","izzzzz",type_id,spos,epos,esize,mpos,msize);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3467,10 +3428,8 @@ H5Tget_ebias(hid_t type_id)
     H5TRACE1("z","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a data type");
-    }
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_FLOAT != dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, 0,
@@ -3509,10 +3468,8 @@ H5Tset_ebias(hid_t type_id, size_t ebias)
     H5TRACE2("e","iz",type_id,ebias);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3558,11 +3515,8 @@ H5Tget_norm(hid_t type_id)
     H5TRACE1("Tn","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NORM_ERROR,
-		      "not a data type");
-    }
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NORM_ERROR, "not a data type");
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_FLOAT != dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_NORM_ERROR,
@@ -3602,10 +3556,8 @@ H5Tset_norm(hid_t type_id, H5T_norm_t norm)
     H5TRACE2("e","iTn",type_id,norm);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3655,11 +3607,8 @@ H5Tget_inpad(hid_t type_id)
     H5TRACE1("Tp","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_PAD_ERROR,
-		      "not a data type");
-    }
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_PAD_ERROR, "not a data type");
     if (dt->parent) dt = dt->parent; /*defer to parent*/
     if (H5T_FLOAT != dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5T_PAD_ERROR,
@@ -3701,10 +3650,8 @@ H5Tset_inpad(hid_t type_id, H5T_pad_t pad)
     H5TRACE2("e","iTp",type_id,pad);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3754,11 +3701,8 @@ H5Tget_cset(hid_t type_id)
     H5TRACE1("Tc","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
-	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_CSET_ERROR,
-		      "not a data type");
-    }
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
+	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_CSET_ERROR, "not a data type");
     /* Don't see any reason for this.  Causes problem for variable-length
      *  string. -SLU (& QAK) */
     /*if (dt->parent) dt = dt->parent;*/ /*defer to parent*/
@@ -3808,10 +3752,8 @@ H5Tset_cset(hid_t type_id, H5T_cset_t cset)
     H5TRACE2("e","iTc",type_id,cset);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3872,10 +3814,8 @@ H5Tget_strpad(hid_t type_id)
     H5TRACE1("Tz","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_STR_ERROR, "not a data type");
-    }
     /* Don't see any reason for this.  Causes problem for variable-length
      *  string. -SLU (& QAK) */
     /* if (dt->parent) dt = dt->parent;*/ /*defer to parent*/
@@ -3936,10 +3876,8 @@ H5Tset_strpad(hid_t type_id, H5T_str_t strpad)
     H5TRACE2("e","iTz",type_id,strpad);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -3998,10 +3936,8 @@ H5Tget_nmembers(hid_t type_id)
     H5TRACE1("Is","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
 
     if (H5T_COMPOUND==dt->type) {
 	ret_value = dt->u.compnd.nmembs;
@@ -4046,10 +3982,8 @@ H5Tget_member_name(hid_t type_id, int membno)
     FUNC_ENTER_API(H5Tget_member_name, NULL);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a data type");
-    }
 
     switch (dt->type) {
     case H5T_COMPOUND:
@@ -4108,7 +4042,7 @@ H5Tget_member_index(hid_t type_id, const char *name)
 
     /* Check arguments */
     assert(name);
-    if(H5I_DATATYPE!=H5I_get_type(type_id) || NULL==(dt=H5I_object(type_id)))
+    if(NULL==(dt=H5I_object_verify(type_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
 
     /* Locate member by name */
@@ -4167,11 +4101,9 @@ H5Tget_member_offset(hid_t type_id, int membno)
     H5TRACE2("z","iIs",type_id,membno);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id)) ||
-	H5T_COMPOUND != dt->type) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)) ||
+            H5T_COMPOUND != dt->type)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, 0, "not a compound data type");
-    }
     if (membno < 0 || membno >= dt->u.compnd.nmembs) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, 0, "invalid member number");
     }
@@ -4209,8 +4141,7 @@ H5Tget_member_class(hid_t type_id, int membno)
     H5TRACE2("Tt","iIs",type_id,membno);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-            NULL == (dt = H5I_object(type_id)) || H5T_COMPOUND != dt->type)
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)) || H5T_COMPOUND != dt->type)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5T_NO_CLASS, "not a compound data type");
     if (membno < 0 || membno >= dt->u.compnd.nmembs)
         HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, H5T_NO_CLASS, "invalid member number");
@@ -4256,11 +4187,8 @@ H5Tget_member_type(hid_t type_id, int membno)
     H5TRACE2("i","iIs",type_id,membno);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id)) ||
-	H5T_COMPOUND != dt->type) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)) || H5T_COMPOUND != dt->type)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a compound data type");
-    }
     if (membno < 0 || membno >= dt->u.compnd.nmembs) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid member number");
     }
@@ -4317,21 +4245,17 @@ H5Tinsert(hid_t parent_id, const char *name, size_t offset, hid_t member_id)
     /* Check args */
     if (parent_id==member_id)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "can't insert compound datatype within itself");
-    if (H5I_DATATYPE != H5I_get_type(parent_id) ||
-	NULL == (parent = H5I_object(parent_id)) ||
-	H5T_COMPOUND != parent->type) {
+    if (NULL == (parent = H5I_object_verify(parent_id,H5I_DATATYPE)) ||
+            H5T_COMPOUND != parent->type)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a compound data type");
-    }
     if (H5T_STATE_TRANSIENT!=parent->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "parent type read-only");
     }
     if (!name || !*name) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no member name");
     }
-    if (H5I_DATATYPE != H5I_get_type(member_id) ||
-	NULL == (member = H5I_object(member_id))) {
+    if (NULL == (member = H5I_object_verify(member_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
 
     /* Insert */
     if (H5T_insert(parent, name, offset, member) < 0) {
@@ -4367,11 +4291,9 @@ H5Tpack(hid_t type_id)
     H5TRACE1("e","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id)) ||
-	H5T_COMPOUND != dt->type) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)) ||
+            H5T_COMPOUND != dt->type)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a compound data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "data type is read-only");
     }
@@ -4414,11 +4336,9 @@ H5Tenum_create(hid_t parent_id)
     H5TRACE1("i","i",parent_id);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(parent_id) ||
-	NULL==(parent=H5I_object(parent_id)) ||
-	H5T_INTEGER!=parent->type) {
+    if (NULL==(parent=H5I_object_verify(parent_id,H5I_DATATYPE)) ||
+            H5T_INTEGER!=parent->type)
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an integer data type");
-    }
 
     /* Build new type */
     if (NULL==(dt = H5FL_ALLOC(H5T_t,1))) {
@@ -4470,10 +4390,8 @@ H5Tenum_insert(hid_t type, const char *name, void *value)
     H5TRACE3("e","isx",type,name,value);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type) ||
-	NULL==(dt=H5I_object(type))) {
+    if (NULL==(dt=H5I_object_verify(type,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_ENUM!=dt->type) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
 		      "not an enumeration data type");
@@ -4521,10 +4439,8 @@ H5Tget_super(hid_t type)
     FUNC_ENTER_API(H5Tget_super, FAIL);
     H5TRACE1("i","i",type);
 
-    if (H5I_DATATYPE!=H5I_get_type(type) ||
-	NULL==(dt=H5I_object(type))) {
+    if (NULL==(dt=H5I_object_verify(type,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (!dt->parent) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "not a derived data type");
     }
@@ -4567,10 +4483,8 @@ H5Tget_member_value(hid_t type, int membno, void *value/*out*/)
     FUNC_ENTER_API(H5Tget_member_value, FAIL);
     H5TRACE3("i","iIsx",type,membno,value);
 
-    if (H5I_DATATYPE!=H5I_get_type(type) ||
-	NULL==(dt=H5I_object(type))) {
+    if (NULL==(dt=H5I_object_verify(type,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_ENUM!=dt->type) {
 	HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
 		      "operation not defined for data type class");
@@ -4619,10 +4533,8 @@ H5Tenum_nameof(hid_t type, void *value, char *name/*out*/, size_t size)
     H5TRACE4("e","ixxz",type,value,name,size);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type) ||
-	NULL==(dt=H5I_object(type))) {
+    if (NULL==(dt=H5I_object_verify(type,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_ENUM!=dt->type) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
 		      "not an enumeration data type");
@@ -4669,10 +4581,8 @@ H5Tenum_valueof(hid_t type, const char *name, void *value/*out*/)
     H5TRACE3("e","isx",type,name,value);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type) ||
-	NULL==(dt=H5I_object(type))) {
+    if (NULL==(dt=H5I_object_verify(type,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_ENUM!=dt->type) {
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
 		      "not an enumeration data type");
@@ -4775,7 +4685,7 @@ H5Tvlen_create(hid_t base_id)
     H5TRACE1("i","i",base_id);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(base_id) || NULL==(base=H5I_object(base_id)))
+    if (NULL==(base=H5I_object_verify(base_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an valid base datatype");
 
     /* Create up VL datatype */
@@ -4813,10 +4723,8 @@ H5Tset_tag(hid_t type_id, const char *tag)
     H5TRACE2("e","is",type_id,tag);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) ||
-	NULL == (dt = H5I_object(type_id))) {
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
     if (H5T_STATE_TRANSIENT!=dt->state) {
 	HRETURN_ERROR(H5E_ARGS, H5E_CANTINIT, FAIL, "data type is read-only");
     }
@@ -4858,7 +4766,7 @@ H5Tget_tag(hid_t type_id)
     FUNC_ENTER_API(H5Tget_tag, NULL);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(type_id) || NULL == (dt = H5I_object(type_id)))
+    if (NULL == (dt = H5I_object_verify(type_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a data type");
 
     if (dt->parent)
@@ -5077,9 +4985,9 @@ H5Tregister(H5T_pers_t pers, const char *name, hid_t src_id, hid_t dst_id,
 	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid function persistence");
     if (!name || !*name)
 	HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "conversion must have a name for debugging");
-    if (H5I_DATATYPE!=H5I_get_type(src_id) || NULL==(src=H5I_object(src_id)))
+    if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    if (H5I_DATATYPE!=H5I_get_type(dst_id) || NULL==(dst=H5I_object(dst_id)))
+    if (NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
     if (!func)
 	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "no conversion function specified");
@@ -5205,12 +5113,9 @@ H5Tunregister(H5T_pers_t pers, const char *name, hid_t src_id, hid_t dst_id,
     H5TRACE5("e","Tesiix",pers,name,src_id,dst_id,func);
 
     /* Check arguments */
-    if (src_id>0 && (H5I_DATATYPE!=H5I_get_type(src_id) ||
-            NULL==(src=H5I_object(src_id)))) {
+    if (src_id>0 && (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE))))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "src is not a data type");
-    }
-    if (dst_id>0 && (H5I_DATATYPE!=H5I_get_type(dst_id) ||
-            NULL==(dst=H5I_object(dst_id)))) {
+    if (dst_id>0 && (NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))) {
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "dst is not a data type");
     }
 
@@ -5252,12 +5157,9 @@ H5Tfind(hid_t src_id, hid_t dst_id, H5T_cdata_t **pcdata)
     H5TRACE3("x","iix",src_id,dst_id,pcdata);
 
     /* Check args */
-    if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	NULL == (src = H5I_object(src_id)) ||
-	H5I_DATATYPE != H5I_get_type(dst_id) ||
-	NULL == (dst = H5I_object(dst_id))) {
+    if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+            NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not a data type");
-    }
     if (!pcdata) {
 	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, NULL,
 		       "no address to receive cdata pointer");
@@ -5313,11 +5215,10 @@ H5Tconvert(hid_t src_id, hid_t dst_id, hsize_t nelmts, void *buf,
     H5TRACE6("e","iihxxi",src_id,dst_id,nelmts,buf,background,plist_id);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(src_id) || NULL==(src=H5I_object(src_id)) ||
-        H5I_DATATYPE!=H5I_get_type(dst_id) || NULL==(dst=H5I_object(dst_id)) ||
-        (H5P_DEFAULT!=plist_id && TRUE != H5P_isa_class(plist_id, H5P_DATASET_XFER))) {
+    if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+            NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)) ||
+            (H5P_DEFAULT!=plist_id && TRUE != H5P_isa_class(plist_id, H5P_DATASET_XFER)))
 	HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-    }
 
     /* Find the conversion function */
     if (NULL==(tpath=H5T_path_find(src, dst, NULL, NULL))) {
@@ -7939,7 +7840,7 @@ H5Tarray_create(hid_t base_id, int ndims, const hsize_t dim[/* ndims */],
     for(i=0; i<ndims; i++)
         if(!(dim[i]>0))
             HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "zero-sized dimension specified");
-    if (H5I_DATATYPE!=H5I_get_type(base_id) || NULL==(base=H5I_object(base_id)))
+    if (NULL==(base=H5I_object_verify(base_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an valid base datatype");
 
     /* Create the actual array datatype */
@@ -8050,7 +7951,7 @@ H5Tget_array_ndims(hid_t type_id)
     H5TRACE1("Is","i",type_id);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type_id) || NULL==(dt=H5I_object(type_id)))
+    if (NULL==(dt=H5I_object_verify(type_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype object");
     if(dt->type!=H5T_ARRAY)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an array datatype");
@@ -8088,7 +7989,7 @@ H5Tget_array_dims(hid_t type_id, hsize_t dims[], int perm[])
     H5TRACE3("e","i*h*Is",type_id,dims,perm);
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type_id) || NULL==(dt=H5I_object(type_id)))
+    if (NULL==(dt=H5I_object_verify(type_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a datatype object");
     if(dt->type!=H5T_ARRAY)
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an array datatype");
diff --git a/src/H5Tconv.c b/src/H5Tconv.c
index beeb7bf..f15acf7 100644
--- a/src/H5Tconv.c
+++ b/src/H5Tconv.c
@@ -283,8 +283,8 @@ H5FL_BLK_DEFINE_STATIC(array_seq);
     case H5T_CONV_INIT:							      \
 	/* Sanity check and initialize statistics */			      \
 	cdata->need_bkg = H5T_BKG_NO;					      \
-	if (NULL==(st=H5I_object(src_id)) ||				      \
-	    NULL==(dt=H5I_object(dst_id))) {				      \
+	if (NULL==(st=H5I_object_verify(src_id,H5I_DATATYPE)) ||	      \
+                NULL==(dt=H5I_object_verify(dst_id,H5I_DATATYPE))) {	      \
 	    HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,		      \
 			  "unable to dereference data type object ID");	      \
 	}								      \
@@ -483,12 +483,9 @@ H5T_conv_order_opt(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
     switch (cdata->command) {
     case H5T_CONV_INIT:
 	/* Capability query */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	if (src->size != dst->size ||
 	    0 != src->u.atomic.offset ||
 	    0 != dst->u.atomic.offset ||
@@ -533,12 +530,9 @@ H5T_conv_order_opt(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 
     case H5T_CONV_CONV:
 	/* The conversion */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 
         buf_stride = buf_stride ? buf_stride : src->size;
         switch (src->size) {
@@ -879,12 +873,9 @@ H5T_conv_order(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
     switch (cdata->command) {
     case H5T_CONV_INIT:
 	/* Capability query */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	if (src->size != dst->size ||
 	    0 != src->u.atomic.offset ||
 	    0 != dst->u.atomic.offset ||
@@ -924,12 +915,9 @@ H5T_conv_order(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     case H5T_CONV_CONV:
 	/* The conversion */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 
         buf_stride = buf_stride ? buf_stride : src->size;
         md = src->size / 2;
@@ -991,12 +979,9 @@ H5T_conv_b_b(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
     switch(cdata->command) {
     case H5T_CONV_INIT:
 	/* Capability query */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	if (H5T_ORDER_LE!=src->u.atomic.order &&
 	    H5T_ORDER_BE!=src->u.atomic.order) {
 	    HRETURN_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL,
@@ -1015,12 +1000,9 @@ H5T_conv_b_b(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     case H5T_CONV_CONV:
 	/* Get the data types */
-	if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-	    NULL==(src=H5I_object (src_id)) ||
-	    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-	    NULL==(dst=H5I_object (dst_id))) {
+	if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 
 	/*
 	 * Do we process the values from beginning to end or vice versa? Also,
@@ -1368,12 +1350,9 @@ H5T_conv_struct(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 	 * otherwise initialize the `priv' field of `cdata' with information
 	 * that remains (almost) constant for this conversion path.
 	 */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	assert (H5T_COMPOUND==src->type);
 	assert (H5T_COMPOUND==dst->type);
 
@@ -1398,12 +1377,9 @@ H5T_conv_struct(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 	/*
 	 * Conversion.
 	 */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	assert (priv);
 	assert (bkg && cdata->need_bkg);
 
@@ -1613,12 +1589,9 @@ H5T_conv_struct_opt(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 	 * otherwise initialize the `priv' field of `cdata' with information
 	 * that remains (almost) constant for this conversion path.
 	 */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	assert (H5T_COMPOUND==src->type);
 	assert (H5T_COMPOUND==dst->type);
 
@@ -1687,12 +1660,9 @@ H5T_conv_struct_opt(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 	/*
 	 * Conversion.
 	 */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 
 	/* Update cached data if necessary */
 	if (cdata->recalc && H5T_conv_struct_init (src, dst, cdata)<0) {
@@ -2001,12 +1971,9 @@ H5T_conv_enum(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 	 * the `priv' field of `cdata' with information about the underlying
 	 * integer conversion.
 	 */
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	assert (H5T_ENUM==src->type);
 	assert (H5T_ENUM==dst->type);
 	if (H5T_conv_enum_init(src, dst, cdata)<0) {
@@ -2031,12 +1998,9 @@ H5T_conv_enum(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 	break;
 
     case H5T_CONV_CONV:
-	if (H5I_DATATYPE != H5I_get_type(src_id) ||
-	    NULL == (src = H5I_object(src_id)) ||
-	    H5I_DATATYPE != H5I_get_type(dst_id) ||
-	    NULL == (dst = H5I_object(dst_id))) {
+	if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	assert (H5T_ENUM==src->type);
 	assert (H5T_ENUM==dst->type);
 
@@ -2205,12 +2169,9 @@ H5T_conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
              * information that remains (almost) constant for this
              * conversion path.
              */
-            if (H5I_DATATYPE != H5I_get_type(src_id) ||
-                    NULL == (src = H5I_object(src_id)) ||
-                    H5I_DATATYPE != H5I_get_type(dst_id) ||
-                    NULL == (dst = H5I_object(dst_id))) {
+            if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
             assert (H5T_VLEN==src->type);
             assert (H5T_VLEN==dst->type);
 
@@ -2227,12 +2188,9 @@ H5T_conv_vlen(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
             /*
              * Conversion.
              */
-            if (H5I_DATATYPE != H5I_get_type(src_id) ||
-                    NULL == (src = H5I_object(src_id)) ||
-                    H5I_DATATYPE != H5I_get_type(dst_id) ||
-                    NULL == (dst = H5I_object(dst_id))) {
+            if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
 
             /*
              * Do we process the values from beginning to end or vice
@@ -2492,12 +2450,9 @@ H5T_conv_array(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
              * information that remains (almost) constant for this
              * conversion path.
              */
-            if (H5I_DATATYPE != H5I_get_type(src_id) ||
-                NULL == (src = H5I_object(src_id)) ||
-                H5I_DATATYPE != H5I_get_type(dst_id) ||
-                NULL == (dst = H5I_object(dst_id))) {
+            if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
             assert (H5T_ARRAY==src->type);
             assert (H5T_ARRAY==dst->type);
 
@@ -2526,12 +2481,9 @@ H5T_conv_array(hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
             /*
              * Conversion.
              */
-            if (H5I_DATATYPE != H5I_get_type(src_id) ||
-                NULL == (src = H5I_object(src_id)) ||
-                H5I_DATATYPE != H5I_get_type(dst_id) ||
-                NULL == (dst = H5I_object(dst_id))) {
+            if (NULL == (src = H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL == (dst = H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
 
             /*
              * Do we process the values from beginning to end or vice
@@ -2651,12 +2603,9 @@ H5T_conv_i_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     switch (cdata->command) {
     case H5T_CONV_INIT:
-	if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-	    NULL==(src=H5I_object (src_id)) ||
-	    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-	    NULL==(dst=H5I_object (dst_id))) {
+	if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	if (H5T_ORDER_LE!=src->u.atomic.order &&
 	    H5T_ORDER_BE!=src->u.atomic.order) {
 	    HRETURN_ERROR (H5E_DATATYPE, H5E_UNSUPPORTED, FAIL,
@@ -2679,12 +2628,9 @@ H5T_conv_i_i (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     case H5T_CONV_CONV:
 	/* Get the data types */
-	if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-	    NULL==(src=H5I_object (src_id)) ||
-	    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-	    NULL==(dst=H5I_object (dst_id))) {
+	if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 
 	/*
 	 * Do we process the values from beginning to end or vice versa? Also,
@@ -3000,12 +2946,9 @@ H5T_conv_f_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     switch (cdata->command) {
     case H5T_CONV_INIT:
-	if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-	    NULL==(src_p=H5I_object (src_id)) ||
-	    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-	    NULL==(dst_p=H5I_object (dst_id))) {
+	if (NULL==(src_p=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL==(dst_p=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	src = src_p->u.atomic;
 	dst = dst_p->u.atomic;
 	if (H5T_ORDER_LE!=src.order &&
@@ -3035,12 +2978,9 @@ H5T_conv_f_f (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     case H5T_CONV_CONV:
 	/* Get the data types */
-	if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-	    NULL==(src_p=H5I_object (src_id)) ||
-	    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-	    NULL==(dst_p=H5I_object (dst_id))) {
+	if (NULL==(src_p=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                NULL==(dst_p=H5I_object_verify(dst_id,H5I_DATATYPE)))
 	    HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-	}
 	src = src_p->u.atomic;
 	dst = dst_p->u.atomic;
 	expo_max = ((hssize_t)1 << dst.u.f.esize) - 1;
@@ -3428,12 +3368,9 @@ H5T_conv_s_s (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
     switch (cdata->command) {
         case H5T_CONV_INIT:
-            if (H5I_DATATYPE!=H5I_get_type(src_id) ||
-                NULL==(src=H5I_object(src_id)) ||
-                H5I_DATATYPE!=H5I_get_type(dst_id) ||
-                NULL==(dst=H5I_object(dst_id))) {
+            if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
             if (8*src->size != src->u.atomic.prec ||
                 8*dst->size != dst->u.atomic.prec) {
                 HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "bad precision");
@@ -3458,12 +3395,9 @@ H5T_conv_s_s (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata, hsize_t nelmts,
 
         case H5T_CONV_CONV:
             /* Get the data types */
-            if (H5I_DATATYPE!=H5I_get_type(src_id) ||
-                NULL==(src=H5I_object(src_id)) ||
-                H5I_DATATYPE!=H5I_get_type(dst_id) ||
-                NULL==(dst=H5I_object(dst_id))) {
+            if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL==(dst=H5I_object_verify(dst_id,H5I_DATATYPE)))
                 HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
 
             /*
              * Do we process the values from beginning to end or vice versa? Also,
@@ -6486,11 +6420,9 @@ H5T_conv_float_double (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
     switch (cdata->command) {
         case H5T_CONV_INIT:
             cdata->need_bkg = H5T_BKG_NO;
-            if (NULL==(st=H5I_object(src_id)) ||
-                NULL==(dt=H5I_object(dst_id))) {
-                HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
-                      "unable to dereference data type object ID");
-            }
+            if (NULL==(st=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL==(dt=H5I_object_verify(dst_id,H5I_DATATYPE)))
+                HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to dereference data type object ID");
             if (st->size!=sizeof(float) || dt->size!=sizeof(double)) {
                 HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
                       "disagreement about data type size");
@@ -6609,11 +6541,9 @@ H5T_conv_double_float (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
     switch (cdata->command) {
         case H5T_CONV_INIT:
             cdata->need_bkg = H5T_BKG_NO;
-            if (NULL==(st=H5I_object(src_id)) ||
-                NULL==(dt=H5I_object(dst_id))) {
-                HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
-                      "unable to dereference data type object ID");
-            }
+            if (NULL==(st=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL==(dt=H5I_object_verify(dst_id,H5I_DATATYPE)))
+                HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL, "unable to dereference data type object ID");
             if (st->size!=sizeof(double) || dt->size!=sizeof(float)) {
                 HRETURN_ERROR(H5E_DATATYPE, H5E_CANTINIT, FAIL,
                       "disagreement about data type size");
@@ -6750,12 +6680,9 @@ H5T_conv_i32le_f64le (hid_t src_id, hid_t dst_id, H5T_cdata_t *cdata,
 
         case H5T_CONV_CONV:
             /* The conversion */
-            if (H5I_DATATYPE!=H5I_get_type (src_id) ||
-                    NULL==(src=H5I_object (src_id)) ||
-                    H5I_DATATYPE!=H5I_get_type (dst_id) ||
-                    NULL==H5I_object (dst_id)) {
+            if (NULL==(src=H5I_object_verify(src_id,H5I_DATATYPE)) ||
+                    NULL==H5I_object_verify(dst_id,H5I_DATATYPE))
                 HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
-            }
             
             s = (uint8_t*)buf + (buf_stride?buf_stride:4)*(nelmts-1);
             d = (uint8_t*)buf + (buf_stride?buf_stride:8)*(nelmts-1);
diff --git a/src/H5Tvlen.c b/src/H5Tvlen.c
index 78e5b68..910a4a4 100644
--- a/src/H5Tvlen.c
+++ b/src/H5Tvlen.c
@@ -676,7 +676,7 @@ H5T_vlen_reclaim(void *elem, hid_t type_id, hsize_t UNUSED ndim, hssize_t UNUSED
     assert(H5I_DATATYPE == H5I_get_type(type_id));
 
     /* Check args */
-    if (H5I_DATATYPE!=H5I_get_type(type_id) || NULL==(dt=H5I_object(type_id)))
+    if (NULL==(dt=H5I_object_verify(type_id,H5I_DATATYPE)))
         HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a data type");
 
     /* Get the default dataset transfer property list if the user didn't provide one */