bug#12339: Bug: rm -fr . doesn't dir depth first deletion yet it is documented to do so.

[Linda Walsh]

Eric Blake wrote:
> POSIX does indeed say that, but it applies only when you use 'rm' in a
> standards-compliant invocation; the moment you add --no-preserve-root to
> your invocation, you are no longer using a standards-compliant
> invocation, so all bets are off as far as POSIX goes.
--
        Which under GNU tools has mean when POSIX_CORRECTLY=1 is set
in the environment.

        It is not.

        There is nothing preventing tools functioning in a more userfriendly
manner than POSIX allows in the absence of a request for POSIX_CORRECTLY.

        Unless you are telling me that all GNU utils have removed
that and always run in POSIX mode by default.

        POSIX was designed to be a lowest common denominator --
not a highest level allowed -- that's why under Gnu/Linux it's
only under a specific request for POSIX compat that lowest level
functionality is enforced.