Are any parts of UNIX in public domain?

[Barry Shein]

>Oh, good grief! Do those lawyer types worry about somebody stealing
>a one-liner like exit 0?

For no good reason I'll take a weak stab at rationalizing this, I presume
the lawyers simply decided not to try to sift through everything and make
a decision on each...copyright it all and damn the torpedos. I hope they
show the same laziness in the future.

	-Barry Shein, Boston University