addendum.txt

Busybox, toybox, xv6, NetBSD, OpenBSD, FreeBSD, DragonflyBSD, Ultrix
3.1, IRIX 6.5.5, both versions that shipped with SunOS 4.1.3 (usr.bin
and 5bin), Solaris 2.6, Seventh Edition Unix (1979), Tenth Edition
Unix (1989), and 4.3BSD.

For good measure (and because I suppose I am now committed to
collecting cats) also included are Second Edition Unix (in assembly)
and Inferno's implementation (in Limbo).

There is also an example that ships with the readline source,
apparently; I found it in /usr/share/readline/rlcat.c.  Another
oddity, p9p comes with libbio/bcat.c.

If you have some exotic cats, please feel free to send them.

	Not that we needed all of that for the trip, but once you get
	locked into a serious cat(1) collection, the tendency is to
	push it as far as you can.  The only thing that really worried
	me was the GNU coreutils.  There is nothing in the world more
	helpless and irresponsible and depraved than a man in the
	depths of a version of Unix that has a copyright notice on
	/bin/true.  And I knew we'd get into that rotten stuff pretty
	soon.

	How long could we *maintain* this code?  I wonder.  How long
	before one of us starts raving and jabbering at this boy?
	What will he think then?  This same lonely office park was the
	last known home of Alcatel-Lucent.  Will he make the grim
	connection?

	The read head suddenly veered off the drive and the machine
	came to a halt in the gravel.  I was hurled against the
	ASR-33.  Dennis was slumped over the wheel.  "What’s
	wrong?" I yelled.  "We can’t stop here.  This is cat(1)
	country!"

-- An excerpt from "Fear and EINTR in New Jersey", by Ken S. Thompson.