yes: Simplify, only support one argument

The previous code was too difficult to decipher for such a simple tool.

Since yes(1) is not specified in any standard and several well-known
implementations only support a single argument, do the same here.

Thanks to everyone who offered implementation suggestions in the
hackers@suckless.org email thread.

yes.c

@@ -6,23 +6,20 @@
 static void
 usage(void)
 {
-	eprintf("usage: %s [string ...]\n", argv0);
+	eprintf("usage: %s [string]\n", argv0);
 }
 
 int
 main(int argc, char *argv[])
 {
-	char **p;
+	const char *s;
 
 	ARGBEGIN {
 	default:
 		usage();
 	} ARGEND
 
-	for (p = argv; ; p = (*p && *(p + 1)) ? p + 1 : argv) {
-		fputs(*p ? *p : "y", stdout);
-		putchar((!*p || !*(p + 1)) ? '\n' : ' ');
-	}
-
-	return 1; /* not reached */
+	s = argc ? argv[0] : "y";
+	for (;;)
+		puts(s);
 }