Scratch of the day - "yes" to all

While browsing on /usr/src/usr.bin to kill some time, found "yes". The manpage was simple:

NAME
    yes — be repetitively affirmative

SYNOPSIS
    yes [expletive]

DESCRIPTION
    yes outputs expletive, or, by default, “y”, forever.

So, it repeats "y" forever. A quick try rev up my processor to the max and