* @return This function will return true if MeshLink has queued the message for transmission, and false otherwise.
* A return value of true does not guarantee that the message will actually arrive at the destination.
*/
-extern bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, unsigned int len);
+extern bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len);
+
+/// Query the maximum packet size that can be sent to a node.
+/** This functions returns the maximum size of packets (path MTU) that can be sent to a specific node with meshlink_send().
+ * The path MTU is a property of the path packets will take to the destination node over the Internet.
+ * It can be different for different destination nodes.
+ * and the path MTU can change at any point in time due to changes in the Internet.
+ * Therefore, although this should only occur rarely, it can still happen that packets that do not exceed this size get dropped.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param destination A pointer to a meshlink_node_t describing the destination for the data.
+ *
+ * @return The recommended maximum size of packets that are to be sent to the destination node, 0 if the node is unreachable,
+ * or a negative value in case of an error.
+ */
+extern ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination);
/// Get a handle for a specific node.
/** This function returns a handle for the node with the given name.
*/
extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len);
+/// Hint that a hostname may be found at an address
+/** This function indicates to meshlink that the given hostname is likely found
+ * at the given IP address and port.
+ *
+ * @param mesh A handle which represents an instance of MeshLink.
+ * @param hostname The hostname which can be found at the given address.
+ * The caller is free to overwrite or free this string
+ * once meshlink returns.
+ * @param addr The IP address and port which should be tried for the
+ * given hostname. The caller is free to overwrite or free
+ * this memory once meshlink returns.
+ */
+extern void meshlink_hint_address(meshlink_handle_t *mesh, char *hostname, struct sockaddr *addr);
+
#ifdef __cplusplus
}
#endif