diff --git a/src/main.c b/src/main.c
index 1ba488b..620207e 100644
--- a/src/main.c
+++ b/src/main.c
@@ -135,7 +135,7 @@ int
 main(int argc, char** argv)
 {
     if (argc < 2 || argc > 3) {
-        printf("USAGE: %s, address [port]\n", argv[0]);
+        printf("USAGE: %s, address|hostname [port]\n", argv[0]);
         return 1;
     }