diff --git a/canfdtest.c b/canfdtest.c index cf59a3a..a4b98f5 100644 --- a/canfdtest.c +++ b/canfdtest.c @@ -52,9 +52,11 @@ static int exit_sig; static void print_usage(char *prg) { fprintf(stderr, + "%s - Full-duplex test program (DUT and host part).\n" "Usage: %s [options] \n" "\n" - "Options: -v (low verbosity)\n" + "Options:\n" + " -v (low verbosity)\n" " -vv (high verbosity)\n" " -g (generate messages)\n" " -l COUNT (test loop count)\n" @@ -64,10 +66,12 @@ static void print_usage(char *prg) " are sent back incrementing the CAN id and\n" "all data bytes. The program can be aborted with ^C.\n" "\n" - "Example:\n" - "\ton DUT : %s -v can0\n" - "\ton Host: %s -g -v can2\n", - prg, prg, prg); + "Examples:\n" + "\ton DUT:\n" + "%s -v can0\n" + "\ton Host:\n" + "%s -g -v can2\n", + prg, prg, prg, prg); exit(1); } @@ -320,7 +324,7 @@ int main(int argc, char *argv[]) signal(SIGHUP, signal_handler); signal(SIGINT, signal_handler); - while ((opt = getopt(argc, argv, "gl:v")) != -1) { + while ((opt = getopt(argc, argv, "gl:v?")) != -1) { switch (opt) { case 'v': verbose++; @@ -334,6 +338,7 @@ int main(int argc, char *argv[]) echo_gen = 1; break; + case '?': default: print_usage(basename(argv[0])); break;