1 files changed, 3 insertions, 0 deletions
diff --git a/src/main.c b/src/main.c
index ab10055..b8953fb 100644
--- a/src/main.c
+++ b/src/main.c
@@ -197,6 +197,9 @@ static void parse_args(int argc,
 			return;
 		}
 	}
+
+	fprintf(stderr, "ftag: command \"%s\" unknown\n", argv[0]);
+	exit(EXIT_FAILURE);
 }
 
 int main(int argc, char *argv[])