shuf: with -i LOW-HIGH, do not allow any argv's

function                                             old     new   delta
shuf_main                                            436     441      +5

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/shuf.c

@@ -92,6 +92,9 @@ int shuf_main(int argc, char **argv)
 		char *dash;
 		unsigned lo, hi;
 
+		if (argv[0])
+			bb_show_usage();
+
 		dash = strchr(opt_i_str, '-');
 		if (!dash) {
 			bb_error_msg_and_die("bad range '%s'", opt_i_str);