| From: | Lee Bosch |
| Date: | 18 Mar 2001 at 17:16:29 |
| Subject: | [D5] Re: ArcHandlerEX |
Hello Dave
On 17-Mar-01, you wrote:
>>> I hate to tell you this but .ADZ files are GZIP archives.
>
>> The term "GZIP archives" doesn't make sense as GNUzip, by RFC
>> definition,
> ^^^^^^^^ - you know, 'more than one' - unless you're
That addresses the plural issue (which I didn't raise because it didn't
exist), but that's not what I'm "on about".
> It does make sense when the whole sentence in taken into consideration but
> you only took the last two words, which even by themselves only imply
> 'more than one GZIP archive' _NOT_ 'a GZIP archive can contain more than
> one file' which is what you are on about.
No, what I'm claiming is that gzip does not produce "archive(s)" at all.
It is for that reason alone that I posted the response to what I consider
to be a misrepresentation of the gzip product. gzip produces only a
compressed version of a single file from which only the name and datestamp
can be derived (as you point out, the original filename must be derived by
convention due to CP/M's (and many other operating systems designed more
than 20 years ago) convention of depending on extensions for file
disposition information). If gzip handled "archive(s)", there would be no
reason to wrap it around tar files (which are archives).
>> only operates on individual files. .ADZ files are indeed compressed using
>> gzip but the result of uncompressing is not a collection of files; it is
>> an ADF format file which is used by Amiga emulators to simulate the
>> contents of an Amiga formatted volume.
>
> Ahh, I see what you're getting at... .ADZ archive(s) is/are _not_ created
> by the application of the program _gzip_ upon the original .ADF archive(s)
> in the process _not_ creating GZIP archive(s) ;^)
How you got from what I posted to how you interpreted it must be
comparable to Military Logic or Female Intelligence. [Honest, it was funny
when I heard it the first time.]
I would suggest that .ADZ files be called compressed ADF "volumes" as that
is truly what they represent. By itself, gzip cannot produce what we
typically call archives in the sense of ARC, ARJ, LhA, RAR, Zip and the
like. If you wanted to be arugmentative, you could say that gzip
"archives" a single "ordered collection of bytes" (a file) but so do any of
the XPK crunchers (compressors). On the Amiga especially, we must
differentiate between XPK crunchers and XPK archivers as they are
completely different animals. I claim that gzip is a cruncher, not an
archiver. On the other hand, tar (Tape ARchiver) is a classic archiver
which takes a directory tree worth of files and assembles them into a
single file. tar, usually by default, makes no attempt to compress the
file (though under many unixen, it can be instructed to pass the files
through the compress, bzip or gzip "filters").
Without considering copyrights, DMS (or one of the other widely used Amiga
side whole volume compress-to-file utilities) would have probably been a
more suitable format for UAE's purpose as it can be easily worked with in
compressed form (in addition to being nicely supported on the Amiga side).
Lee Bosch