[Info-vax] ZIP and UNZIP maximum file size

[Lester Dreckow]

On Nov 29, 3:37 pm, Steven Schweda <sms.antin... at gmail.com> wrote:
> On Nov 28, 11:54 pm, Lester Dreckow <lester.drec... at gmail.com> wrote:
>
> > [...] do we know what the upper limit is?
>
>    Assuming that "[un]zip -v" mentions (both):
>
>         LARGE_FILE_SUPPORT
>         ZIP64_SUPPORT
>
> they should be limited only by the local C run-time or 63
> bits, whichever comes first.
>
> > Best info [...]http://www.info-zip.org/FAQ.html#limits
>
>    Eeew.  Ob-so-lete.  The Zip64 archive format extensions
> alleviate any 2GB/4GB size limit, and the 64K (16-bit) file
> count limit is now a 4G (32-bit) limit.  I'll see if I can
> get that Web page updated.
>
> > But trying it (before finding the above), it has successfully zipped
> > and unzipped a 40GB backup saveset via an 11GB zip file.  "Unzip -t"
> > was OK and DIFF confirmed the resultant unzipped saveset had no
> > differences.
>
>    What could go wrong?  (The stuff was tested on files and
> archives at least bigger than 4GB, and with counts above 64K,
> so I don't expect any size-related problems.  There have been
> some bug fixes in the subsequent beta kits, but none directly
> size related, so far as I can recall.)
>
> > $ set rms/extend=64000
>
>    Note that there's code in [Un]Zip:[.vms]vms.c which should
> set (non-default) large values for some RMS parameters, even
> when the victim doesn't do things like that.  With enough
> "-v" options on the command line, you should get some
> diagnostic messages which reveal what's being done.

Thanks Steven, good to know.  Thanks for all your work on it over the
years.