From ca4b8979b1aeeefbf785a6141761aea26be58451 Mon Sep 17 00:00:00 2001
From: Magnus Jacobsson <magnus.jacobsson@berotec.se>
Date: Fri, 2 Oct 2020 15:19:43 +0200
Subject: [PATCH] Show usage and exit non-zero for unsupported option in nop

Towards https://gitlab.com/graphviz/graphviz/-/issues/1843.
---
 cmd/tools/nop.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/cmd/tools/nop.c b/cmd/tools/nop.c
index a80536fa7..008a5fc8a 100644
--- a/cmd/tools/nop.c
+++ b/cmd/tools/nop.c
@@ -50,9 +50,11 @@ static void init(int argc, char *argv[])
 	case '?':
 	    if (optopt == '?')
 		usage(0);
-	    else
-		fprintf(stderr, "nop: option -%c unrecognized - ignored\n",
+	    else {
+		fprintf(stderr, "nop: option -%c unrecognized\n",
 			optopt);
+		usage(1);
+	    }
 	    break;
 	}
     }
-- 
2.40.0