extern int get_optional_int (std::multimap<std::string, std::string> const & kv, std::string k);
extern std::string get_optional_string (std::multimap<std::string, std::string> const & kv, std::string k);
extern void* wrapped_av_malloc (size_t);
+extern int64_t divide_with_round (int64_t a, int64_t b);
/** @class Socket
* @brief A class to wrap a boost::asio::ip::tcp::socket with some things