Re: Converting disk images to floppies....

[CUTjefbla@bconnex.net (Jeff Blakeney)]

On 6 Jan 1999 05:03:20 GMT, labelas@hotmail.com (Labelas Enoreth)
wrote:

>Just to poke this in, but...I think zip and gz are very close in format,
>except zip being an archive format and .gz being single-file
>compression...(a friend of mine wrote a simple GZ compress/expander for
>MacOS) I don't know why I brought this up, except for the fact that I was
>under the impression that most zip programs could handle gz as well...

Yes, gzip uses one of the types of compression that the zip format
uses.

Each file in a zip file can be compressed using one of several
different types of compression.  Gzip only ever uses one of those
compressions but it is exactly the same as the zip version of that
compression.

The only difference between the two formats is the header info that
gives the file info (names, dates and such).  The gzip format can only
have one file in it (which is why you see .tar.gz a lot because .tar
allows you to put a bunch of files together without compressing them,
then you compress them with gzip) and the zip format allows you to
compress lots of files and store it all in the one .zip file.

gz2pkz for the Apple II just changes the header info of a .gz file so
that it is in .zip format so that regular zip programs for the Apple
II can unpack the file.

By the way, the PKWare package of zip utilities doesn't support direct
unpacking of gzip files.  However, Winzip does but that is an added
function that Winzip added and is not part of the zip format.

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