Man, I hate when this happens—I'm browsing around on the Intarwebs, when I come across a reference to what appears to be some obscure Unix command [1] only to find it's been around for close to thirty years now [2].
Sigh.
That's what I get for not bothering to read up on the 3,300 commands available by default on your typical Unix installation (found by simple invocation of find `echo $PATH | tr : ' '` -type f -perm 755 | wc -l—ain't Unix wonderful?).
[2] http://glomek.blogspot.com/2007/12/unix-makes-computer-science-easy.html