1 files changed, 1 insertions, 1 deletions

diff --git a/plugins/check_http.c b/plugins/check_http.c
index dddddf97..6a216a5c 100644
--- a/plugins/check_http.c
+++ b/plugins/check_http.c
@@ -344,7 +344,7 @@ process_arguments (int argc, char **argv)
 
                 switch (c) {
                 case '?': /* usage */
-                        usage2 ("unknown argument", optarg);
+                        usage3 ("unknown argument", optopt);
                         break;
                 case 'h': /* help */
                         print_help ();