rem: if (argc == 2)
add: if (argc == optind + 1)
context: main (int argc, char **argv){  program_name = argv[0];  setlocale (LC_ALL, "");  bindtextdomain (PACKAGE, LOCALEDIR);  textdomain (PACKAGE);  atexit (close_stdout);  parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,		      AUTHORS, usage);  if (argc == 1)    {      error (0, 0, _("too few arguments"));      usage (EXIT_FAILURE);    }  if (chroot (argv[1]))    error (EXIT_FAILURE, errno,	   _("cannot change root directory to %s"), argv[1]);  if (chdir ("/"))    error (EXIT_FAILURE, errno, _("cannot chdir to root directory"));  if (argc == 2)    {      /* No command.  Run an interactive shell.  */      char *shell = getenv ("SHELL");      if (shell == NULL)	shell = "/bin/sh";      argv[0] = shell;      argv[1] = "-i";    }  else    {      /* The following arguments give the command.  */      argv += 2;    }  /* Execute the given command.  */  execvp (argv[0], argv);  {    int exit_status = (errno == ENOENT ? 127 : 126);    error (0, errno, "%s", argv[0]);    exit (exit_status);  }}