-extern void init_search();
-extern void init_threads();
-extern void exit_threads();
-extern int perft(Position& pos, Depth depth);
-extern int64_t nodes_searched();
-extern bool think(const Position& pos, bool infinite, bool ponder, int time[], int increment[],
- int movesToGo, int maxDepth, int maxNodes, int maxTime, Move searchMoves[]);