--- a/src/ls-oct-ascii.h
+++ b/src/ls-oct-ascii.h
@@ -25,6 +25,10 @@
 
 #include <cfloat>
 
+#include <string>
+
+#include "str-vec.h"
+
 // Flag for cell elements
 #define CELL_ELT_TAG "<cell-element>"
 
@@ -42,6 +46,11 @@
 extract_keyword (std::istream& is, const char *keyword, int& value,
 		 const bool next_only = false);
 
+extern  bool
+extract_keyword (std::istream& is, const string_vector& keywords,
+		 std::string& keyword, int& value,
+		 const bool next_only = false);
+
 extern std::string
 read_ascii_data (std::istream& is, const std::string& filename, bool& global,
 		 octave_value& tc, int count);