cd failure killing script [Re: Interactive 2.2 File zapper]

[Guy Harris]

>If you want a failed cd to kill the script, then do...

If you want a failed "cd" to kill the script, don't bother doing
anything.  The SunOS 4.0.3 Bourne shell, based on the S5R3.1 one, will
kill the script if a "cd" fails; I checked the source code to the 4.3BSD
Bourne shell, based on the V7 one, and it appears as if it'll do the
same.

Given that, and given that, as far as I know, neither Sun nor Berkeley
introduced this feature, it's probably in most if not all UNIX Bourne
shells, going back at least as far as V7 (it existed, at least within
Bell Labs, before V7 came out; I can't speak for those versions).