Prevent unnecessary string copy.

src/grid.c

@@ -4121,6 +4121,12 @@ int gridInqReference(int gridID, char *reference)
   return (len);
 }
 
+const char *gridInqReferencePtr(int gridID)
+{
+  grid_t *gridptr = gridID2Ptr(gridID);
+  return gridptr->reference;
+}
+
 /*
 @Function  gridDefUUID
 @Title     Define the UUID for an unstructured grid

src/grid.h

@@ -132,6 +132,8 @@ const double *gridInqAreaPtr(int gridID);
 const char *gridInqXnamePtr(int gridID);
 const char *gridInqYnamePtr(int gridID);
 
+const char *gridInqReferencePtr(int gridID);
+
 int gridCompare(int gridID, const grid_t *grid);
 int gridGenerate(const grid_t *grid);
 

src/stream_cdf.c

@@ -1740,14 +1740,9 @@ void cdfDefGridReference(stream_t *streamptr, int gridID)
       cdf_put_att_int(fileID, NC_GLOBAL, "number_of_grid_used", NC_INT, 1, &number);
     }
 
-  if ( gridInqReference(gridID, NULL) )
-    {
-      char gridfile[8912];
-      gridInqReference(gridID, gridfile);
-
-      if ( gridfile[0] != 0 )
-        cdf_put_att_text(fileID, NC_GLOBAL, "grid_file_uri", strlen(gridfile), gridfile);
-    }
+  const char *gridfile = gridInqReferencePtr(gridID);
+  if ( gridfile && gridfile[0] != 0 )
+    cdf_put_att_text(fileID, NC_GLOBAL, "grid_file_uri", strlen(gridfile), gridfile);
 }
 
 static