diff --git a/contrib/spoa_example/spoa.c b/contrib/spoa_example/spoa.c
index 9725078..3f96d84 100644
--- a/contrib/spoa_example/spoa.c
+++ b/contrib/spoa_example/spoa.c
@@ -1100,7 +1100,7 @@
 		return;
 
 	list_for_each_entry(eng, &client->worker->engines, list) {
-		if (!strcmp(eng->id, client->engine_id))
+		if (strcmp(eng->id, client->engine_id) == 0)
 			goto end;
 	}
 
@@ -1762,11 +1762,11 @@
 				server_port = atoi(optarg);
 				break;
 			case 'c':
-				if (!strcmp(optarg, "pipelining"))
+				if (strcmp(optarg, "pipelining") == 0)
 					pipelining = true;
-				else if (!strcmp(optarg, "async"))
+				else if (strcmp(optarg, "async") == 0)
 					async = true;
-				else if (!strcmp(optarg, "fragmentation"))
+				else if (strcmp(optarg, "fragmentation") == 0)
 					fragmentation = true;
 				else
 					fprintf(stderr, "WARNING: unsupported capability '%s'\n", optarg);