> I have seen zips in which the two headers each have (different) extra
> fields.

Is that allowed according to the spec? I just looked at pkware's Zip
application note (appnote.txt), and I can't see anywhere that (any of) the
fields in the local header are required to be identical to those in the
central directory entry header. It seems to me though, that they should -
otherwise, which values would you use?  Those in the cdir entry or those in
the local header?

Ned, I just discovered that you wrote a popular Zip module for Perl. I'd be
very interested in your comments about rubyzip. - or indeed your help ;-)

Thomas