Added error checking for polling

include/icsneo/api/error.h

@@ -42,9 +42,10 @@ public:
 		DeviceCurrentlyClosed = 0x1006,
 		DeviceCurrentlyOnline = 0x1007,
 		DeviceCurrentlyOffline = 0x1008,
-		DeviceNotPolling = 0x1009,
-		UnsupportedTXNetwork = 0x1010,
-		MessageMaxLengthExceeded = 0x1011,
+		DeviceCurrentlyPolling = 0x1009,
+		DeviceNotCurrentlyPolling = 0x1010,
+		UnsupportedTXNetwork = 0x1011,
+		MessageMaxLengthExceeded = 0x1012,
 		
 		// Device Errors
 		PollingMessageOverflow = 0x2000,

include/icsneo/device/device.h

@@ -50,7 +50,7 @@ public:
 	virtual bool goOffline();
 
 	// Message polling related functions
-	void enableMessagePolling();
+	bool enableMessagePolling();
 	bool disableMessagePolling();
 	bool isMessagePollingEnabled() { return messagePollingCallbackID != 0; };
 	std::vector<std::shared_ptr<Message>> getMessages();