segway_main: avoid using exit()

src/examples/segway/segway_main.cpp

@@ -78,7 +78,6 @@ usage(const char *reason)
 	}
 
 	fprintf(stderr, "usage: segway {start|stop|status} [-p <additional params>]\n\n");
-	exit(1);
 }
 
 /**
@@ -94,6 +93,7 @@ int segway_main(int argc, char *argv[])
 
 	if (argc < 2) {
 		usage("missing command");
+		return -1;
 	}
 
 	if (!strcmp(argv[1], "start")) {
@@ -101,7 +101,7 @@ int segway_main(int argc, char *argv[])
 		if (thread_running) {
 			warnx("already running");
 			/* this is not an error */
-			exit(0);
+			return 0;
 		}
 
 		thread_should_exit = false;
@@ -112,12 +112,12 @@ int segway_main(int argc, char *argv[])
 						 5120,
 						 segway_thread_main,
 						 (argv) ? (char *const *)&argv[2] : (char *const *)nullptr);
-		exit(0);
+		return 0;
 	}
 
 	if (!strcmp(argv[1], "stop")) {
 		thread_should_exit = true;
-		exit(0);
+		return 0;
 	}
 
 	if (!strcmp(argv[1], "status")) {
@@ -128,11 +128,11 @@ int segway_main(int argc, char *argv[])
 			warnx("not started");
 		}
 
-		exit(0);
+		return 0;
 	}
 
 	usage("unrecognized command");
-	exit(1);
+	return -1;
 }
 
 int segway_thread_main(int argc, char *argv[])