--- listSerialPortsC-1.4.0/main.c~	2016-12-14 18:05:24.000000000 +0100
+++ listSerialPortsC-1.4.0/main.c	2017-02-26 06:39:51.626291800 +0100
@@ -9,7 +9,7 @@
 
     ret = sp_list_ports(&ports);
     if (ret != SP_OK) {
-        return 0;
+        return 1;
     }
 
     struct sp_port *port;
@@ -25,4 +25,6 @@
         sp_free_port(port);
     }
     sp_free_port_list(ports);
+
+    return 0;
 }