Re: PATCH: zsh-4.2.1: unset does not follow spec

["Sean C. Farley" <sean@xxxxxxxxxx>]

On Wed, 22 Sep 2004, Bart Schaefer wrote:

> 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).

This is also in the spec:

    Unsetting a variable or function that was not previously set shall
    not be considered an error and does not cause the shell to abort.

I assume non-zero is an error.

> 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.

> From your comment, it sounds like hell might freeze over first.  :)

I can see where both views are correct.  Let me know when you hear back
from them.

Sean
---------------
sean@xxxxxxxxxx