Const is good... -mi --- src/Guesser.h 2010-09-27 19:02:01.000000000 -0400 +++ src/Guesser.h 2015-03-23 11:42:51.000000000 -0400 @@ -20,5 +20,5 @@ { public: - bool operator()( const SocketPair &sp1, const SocketPair & sp2 ) + bool operator()( const SocketPair &sp1, const SocketPair & sp2 ) const { if( sp1==sp2 ) --- src/TCContainer.h 2010-09-27 19:02:01.000000000 -0400 +++ src/TCContainer.h 2015-03-23 11:40:43.000000000 -0400 @@ -58,5 +58,5 @@ { public: - bool operator()( const SocketPair &sp1, const SocketPair &sp2 ) + bool operator()( const SocketPair &sp1, const SocketPair &sp2 ) const { if( sp1==sp2 )