Convert K&R function definition to ansi to make clang 15 happier

Mark functions that do not return as __dead to quiet gcc warnings.

ok beck@

add missing 'void'

ok mestre@

Pledge for backgammon and teachgammon.

Both are straightforward "stdio rpath tty" programs; teachgammon
exec's backgammon at the end, so give it "exec" in addition.

While there, ANSIfy

rcsid[] and sccsid[] and copyright[] are essentially unmaintained (and
unmaintainable). these days, people use source. these id's do not provide
any benefit, and do hurt the small install media
(th

rcsid[] and sccsid[] and copyright[] are essentially unmaintained (and
unmaintainable). these days, people use source. these id's do not provide
any benefit, and do hurt the small install media
(the 33,000 line diff is essentially mechanical)
ok with the idea millert, ok dms

show more ...

Remove the advertising clause in the UCB license which Berkeley
rescinded 22 July 1999. Proofed by myself and Theo.

termios -> curses

use const where appropriate (jsm28@cam.ac.uk). Also some very minor tidying.

NetBSD changes and further improvements and corrections

initial import of NetBSD tree