diff -r cd72eae05bdf -r 3c00344f49c9 lemon/lp_skeleton.h
--- a/lemon/lp_skeleton.h	Mon Jul 16 16:21:40 2018 +0200
+++ b/lemon/lp_skeleton.h	Wed Oct 17 19:14:07 2018 +0200
@@ -2,7 +2,7 @@
  *
  * This file is a part of LEMON, a generic C++ optimization library.
  *
- * Copyright (C) 2003-2010
+ * Copyright (C) 2003-2013
  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
  * (Egervary Research Group on Combinatorial Optimization, EGRES).
  *
@@ -144,6 +144,10 @@
 
     ///\e
     virtual void _messageLevel(MessageLevel);
+
+    ///\e
+    virtual void _write(std::string file, std::string format) const;
+
   };
 
   /// \brief Skeleton class for an LP solver interface
@@ -222,6 +226,7 @@
 
     ///\e
     virtual const char* _solverName() const;
+
   };
 
 } //namespace lemon