Update ua_client_highlevel_subscriptions.c

src/client/ua_client_highlevel_subscriptions.c

@@ -91,7 +91,7 @@ UA_StatusCode UA_Client_Subscriptions_remove(UA_Client *client, UA_UInt32 subscr
 UA_StatusCode
 UA_Client_Subscriptions_addMonitoredItem(UA_Client *client, UA_UInt32 subscriptionId,
                                          UA_NodeId nodeId, UA_UInt32 attributeID,
-                                         void *handlingFunction, void *handlingContext,
+                                         void (*handlingFunction)(UA_UInt32 handle, UA_DataValue *value, void *context), void *handlingContext,
                                          UA_UInt32 *newMonitoredItemId) {
     UA_Client_Subscription *sub;
     LIST_FOREACH(sub, &client->subscriptions, listEntry) {