if (seteuid (uid) < 0)
die ();
console_fd = open (tty_name, O_RDONLY);
console_fd = open (tty_name, O_RDONLY | O_NONBLOCK);
if (console_fd < 0)
if (fstat (console_fd, &st) < 0 || ! S_ISCHR (st.st_mode))