err (1, dev);
err (1, "%s", dev);
int main(argc, argv)	int argc;	char *argv[];{	int ch, fd, blank;	char *ep, *dev = _PATH_CONSOLE;	blank = -1;	while ((ch = getopt(argc, argv, "b:f:")) != -1) {		switch (ch) {		case 'b':			blank = strtol(optarg, &ep, 10);			if (ep == optarg)				errx (1, "numeric argument expected");			if (blank < 0)				errx (1, "illegal blank value");			break;		case 'f':			dev = optarg;			break;		default:			fprintf (stderr,				"usage: %s [-f device] [-b interval]\n",				__progname);			exit (1);		}	}	fd = open (dev, O_RDWR);	if (fd < 0)		err (1, dev);	if (blank >= 0) {		if (ioctl(fd, CONSOLE_SET_BLANK, &blank) < 0)			err (1, "ioctl");	}	close (fd);	exit (0);}