Index: /trunk/doc/pslib/ChangeLogSDRS.tex
===================================================================
--- /trunk/doc/pslib/ChangeLogSDRS.tex	(revision 4085)
+++ /trunk/doc/pslib/ChangeLogSDRS.tex	(revision 4086)
@@ -1,3 +1,3 @@
-%%% $Id: ChangeLogSDRS.tex,v 1.121 2005-06-02 00:58:26 jhoblitt Exp $
+%%% $Id: ChangeLogSDRS.tex,v 1.122 2005-06-02 04:13:41 jhoblitt Exp $
 
 \subsection{Changes from version 00 to version 01}
@@ -665,3 +665,4 @@
   \item change \code{psBitSet} to store it's size as an \code{long int}
 \end{itemize}
-\end{itemize}
+\item add \code{PS_META_NULL}
+\end{itemize}
Index: /trunk/doc/pslib/psLibSDRS.tex
===================================================================
--- /trunk/doc/pslib/psLibSDRS.tex	(revision 4085)
+++ /trunk/doc/pslib/psLibSDRS.tex	(revision 4086)
@@ -1,3 +1,3 @@
-%%% $Id: psLibSDRS.tex,v 1.257 2005-06-02 00:58:26 jhoblitt Exp $
+%%% $Id: psLibSDRS.tex,v 1.258 2005-06-02 04:13:41 jhoblitt Exp $
 \documentclass[panstarrs,spec]{panstarrs}
 
@@ -4078,7 +4078,8 @@
 \begin{datatype}
 typedef enum {                          ///< option flags for psMetadata functions
-    PS_META_DEFAULT,                    ///< default behavior (0x0000) for use in mode above
-    PS_META_REPLACE,                    ///< allow entry to be replaced
-    PS_META_DUPLICATE_OK,               ///< allow entry to be replaced
+    PS_META_DEFAULT         = 0,        ///< default behavior (0x0000) for use in mode above
+    PS_META_REPLACE         = 0x1000000 ///< allow entry to be replaced
+    PS_META_DUPLICATE_OK    = 0x2000000 ///< allow duplicate entries
+    PS_META_NULL            = 0x4000000 ///< psMetadataItem.data is a NULL value
 } psMetadataFlags;
 \end{datatype}
@@ -4105,4 +4106,10 @@
 contain both the existing item and the new item.  The original entry's
 location on the psMetadata.list must be maintained.
+
+\code{PS_META_NULL}:  Indicates that \code{psMetadataItem.data} should be
+ignored and that the the current value is ``NULL'' or undefined.  The
+\code{psMetadataItem} must have a proper \code{type} set and it's \code{data}
+field shall have a valid value.  e.g. A \code{type} of \code{PS_META_STR} would
+require that 's \code{data} is set to \code{NULL}.
 
 There are several of cases to handle for duplication of an existing