hdf5: add attribute access to Group

Author: delaneyj

h5d_dataset.go

@@ -167,8 +167,7 @@ func (s *Dataset) CreateAttributeWith(name string, dtype *Datatype, dspace *Data
 }
 
 // Opens an existing attribute. The returned attribute must be closed
-// by the user when it is no longer needed. The returned attribute
-// must be closed by the user when it is no longer needed.
+// by the user when it is no longer needed.
 func (s *Dataset) OpenAttribute(name string) (*Attribute, error) {
 	return openAttribute(s.id, name)
 }

h5g_group.go

@@ -66,6 +66,12 @@ func (g *Group) CreateAttributeWith(name string, dtype *Datatype, dspace *Datasp
 	return createAttribute(g.id, name, dtype, dspace, acpl)
 }
 
+// Opens an existing attribute. The returned attribute must be closed
+// by the user when it is no longer needed.
+func (g *Group) OpenAttribute(name string) (*Attribute, error) {
+	return openAttribute(g.id, name)
+}
+
 // Close closes the Group.
 func (g *Group) Close() error {
 	return g.closeWith(h5gclose)