On Wed, 22 Sep 2004, Sean C. Farley wrote:

> Recently, I read that FreeBSD's /bin/sh fails:
> http://www.freebsd.org/cgi/query-pr.cgi?pr=standards/45738
> the IEEE Std 1003.1-2001:
> http://www.opengroup.org/onlinepubs/007904975/utilities/unset.html
> when it comes to the builtin unset.  tcsh and bash do follow it.

I don't see how zsh "fails" this specification.

EXIT STATUS

     0
        All name operands were successfully unset.
    >0
        At least one name could not be unset.

It appears to me that FreeBSD and Zsh are interpreting "could not be 
unset" to include variables that were not set in the first place.  After 
all, if it isn't set, you can't UNset it, can you?  It doesn't say "0 if
all name operands end up unset after this is finished, regardless of their
previous state" (which is how bash and tcsh appear to interpret it).

I'm going to ask about this on the austin-group list.  It'll give them 
something to discuss that they might actually come to agreement on.