change PIIODevice read* and write* methods size to "ssize_t"

utils/udp_file_transfer/main.cpp

@@ -50,7 +50,7 @@ public:
 			CONNECTU(&ft, sendFilesFinished, this, ftevent);
 			CONNECTU(&ft, receiveFilesFinished, this, ftevent);
 		}
-		CONNECT2(void, const uchar *, int, &eth, threadedReadEvent, this, received);
+		CONNECT2(void, const uchar *, ssize_t, &eth, threadedReadEvent, this, received);
 		start(50);
 		eth.setParameter(PIEthernet::SeparateSockets);
 		eth.startThreadedRead();
@@ -136,7 +136,7 @@ private:
 		eth.send(data);
 	}
 
-	EVENT_HANDLER2(void, received, const uchar * , readed, int, size) {
+	EVENT_HANDLER2(void, received, const uchar * , readed, ssize_t, size) {
 		PIByteArray ba(readed, size);
 		if(test_) {
 			testt.received(ba);