I realize I have been bitten by zsh-centric behaviour.

Given the path /a/b/c/.. and given that c is a symlink to /x/y/z I got different results depending on which shell I used when I said. sh, csh and tcsh all said the correct answer was /x/y. ksh, bash and zsh said /a/b was the correct answer.
Therefore, some shells are broken and some are not.

According to the FreeBSD manpage, there is a POSIX.2 specified behaviour for cd. I am not aware that I have access to the POSIX.2 standards. Can somebody who does have access tell me if POSIX.2 defines the behaviour of cd in this case?

Thanks,
Mik