rem: usage (2);
add: usage (EXIT_FAILURE);
context: getoptarg (char *arg, char switch_char, char *character, int *number){  if (!ISDIGIT (*arg))    *character = *arg++;  if (*arg)    {      long int tmp_long;      if (xstrtol (arg, NULL, 10, &tmp_long, "") != LONGINT_OK	  || tmp_long <= 0 || tmp_long > INT_MAX)	{	  error (0, 0,		 _("`-%c' extra characters or invalid number in the argument: `%s'"),		 switch_char, arg);	  usage (2);	}      *number = (int) tmp_long;    }}