diff --git a/sys/comm.h b/sys/comm.h
new file mode 100644
index 0000000..16aeb33
--- /dev/null
+++ b/sys/comm.h
@@ -0,0 +1,15 @@
+#ifndef LPC_COMM_H_
+#define LPC_COMM_H_
+
+/* return values for net_connect() */
+
+#define NC_SUCCESS         0  /* Success! */
+#define NC_EUNKNOWNHOST    1  /* host address could not be resolved */
+#define NC_ENOSOCKET       2  /* socket could not be created */
+#define NC_ENOBIND         3  /* socket could not be bound */
+#define NC_ENOCONNECT      4  /* socket could not be connected */
+#define NC_ECONNREFUSED    5  /* target address not listening */
+#define NC_EMCONN          6  /* too many pending connections */
+#define NC_ENORESSOURCES   7  /* insufficient system ressources */
+
+#endif /* LPC_COMM_H_ */