[EchoClient] output buffers if they do not match

apps/EchoClient.cpp

@@ -177,7 +177,19 @@ static void clientFunc(uint64_t client_id, Semaphore& readySem, Semaphore& start
 		}
 
 		if (memcmp(outBuf, inBuf, size) != 0) {
-			DIE_MSG("got unexpected echo from server");
+			std::cerr << "got unexpected echo from server" << std::endl;
+			std::cerr << "expected: " << std::hex;
+			for (unsigned i = 0; i < size; ++i) {
+				std::cerr << (unsigned)outBuf[i] << " ";
+			}
+			std::cerr << std::endl;
+
+			std::cerr << "received: " << std::hex;
+			for (unsigned i = 0; i < size; ++i) {
+				std::cerr << (unsigned)inBuf[i] << " ";
+			}
+			std::cerr << std::endl;
+			DIE;
 		}
 
 		i++;