[svn-r9727] Purpose:

    Bug Fix/Code Cleanup/Doc Cleanup/Optimization/Branch Sync :-)

Description:
    Generally speaking, this is the "signed->unsigned" change to selections.
However, in the process of merging code back, things got stickier and stickier
until I ended up doing a big "sync the two branches up" operation.  So... I
brought back all the "infrastructure" fixes from the development branch to the
release branch (which I think were actually making some improvement in
performance) as well as fixed several bugs which had been fixed in one branch,
but not the other.

    I've also tagged the repository before making this checkin with the label
"before_signed_unsigned_changes".

Platforms tested:
    FreeBSD 4.10 (sleipnir) w/parallel & fphdf5
    FreeBSD 4.10 (sleipnir) w/threadsafe
    FreeBSD 4.10 (sleipnir) w/backward compatibility
    Solaris 2.7 (arabica) w/"purify options"
    Solaris 2.8 (sol) w/FORTRAN & C++
    AIX 5.x (copper) w/parallel & FORTRAN
    IRIX64 6.5 (modi4) w/FORTRAN
    Linux 2.4 (heping) w/FORTRAN & C++


Misc. update:

1 files changed, 87 insertions, 0 deletions

diff --git a/test/gen_nullspace.c b/test/gen_nullspace.c
new file mode 100644
index 0000000..5892443
--- /dev/null
+++ b/test/gen_nullspace.c
@@ -0,0 +1,87 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Programmer:  Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *              Saturday, April 17, 2004
+ *
+ * Purpose:	Create a dataset with a null dataspace and an attribute
+ *      with a null dataspace.
+ *		This program is used to create the test file `tnullspace.h5' which
+ *      has dataspaces stored in the newer (version 2) style in the object headers.
+ *		To build the test file, this program MUST be compiled and linked with
+ *      the hdf5-1.7+ series of libraries and the generated test file must be
+ *      put into the 'test' directory in the 1.6.x branch of the library.
+ */
+
+#include "hdf5.h"
+#include <assert.h>
+
+#define NULLFILE   "tnullspace.h5"
+#define NULLDATASET  "null_dataset"
+#define NULLATTR   "null_attribute"
+
+int
+main(void)
+{
+    hid_t fid;          /* File ID */
+    hid_t gid;          /* Group ID */
+    hid_t sid;          /* Dataspace ID */
+    hid_t did;          /* Dataset ID */
+    hid_t attr;         /* Attribute ID */
+    herr_t ret;         /* Generic return value */
+    
+    /* Create the file */
+    fid = H5Fcreate(NULLFILE, H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+    assert(fid>0);
+
+    sid = H5Screate(H5S_NULL);
+    assert(sid>0);
+    
+    /* Create dataset */
+    did = H5Dcreate(fid, NULLDATASET, H5T_NATIVE_UINT, sid, H5P_DEFAULT);
+    assert(did>0);
+    
+    /* Close the dataset */
+    ret = H5Dclose(did);
+    assert(ret>=0);
+
+    /* Open the root group */
+    gid = H5Gopen(fid,"/");
+    assert(gid>0);
+
+    /* Create an attribute for the group */
+    attr=H5Acreate(gid,NULLATTR,H5T_NATIVE_INT,sid,H5P_DEFAULT);
+    assert(attr>0);
+    
+    /* Close attribute */
+    ret=H5Aclose(attr);
+    assert(ret>=0);
+  
+    /* Close the group */
+    ret = H5Gclose(gid);
+    assert(ret>=0);
+   
+    /* Close the dataspace */
+    ret = H5Sclose(sid);
+    assert(ret>=0);
+    
+    /* Close the file */
+    ret = H5Fclose(fid);
+    assert(ret>=0);
+   
+    return 0;
+}
+
+