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MacGzip 1.1.3 (gzip 1.2.4)

MacGzip is Jean-loup Gailly's gzip compressor (GNU zip) for the Macintosh, ported to Mac by SPDsoft. (If you have any comment about MacGzip, please send it to me <>, not to Jean-loup Gailly.)

MacGzip requires system 7 or better, and it should work in any Macintosh if you have the correct combination of software and CPU (if you want to know which version of MacGzip you have, choose 'get info' from the finder; 68K and FAT run on any Macintosh (FAT runs native for Power Macs); and the version for Power Mac only runs on Power Macs)

MacGzip works better if you have Internet Config installed;

gzip is not an archiver, but a compressor. A compressor makes a compressed file for every plain file; an archiver will make a single compressed file from a set of files/directories. Maybe some day I will try to port GNU tar (the natural archiver to be used with gzip) to Macintosh, but don't rely on this...

You should read the files in 'GNU docs' folder...

* Configuring MacGzip

The easiest way to use MacGzip is as a Drag & Drop tool; depending on what you enter in the preferences dialog, the use can be fully automatic or manual.

Note: 'Drag&Drop keys' are the keys you push while dragging a files/folders on MacGzip. You should hold them down until the window (for the first file) appears.

- gzip standard options:

* gzip suffix:

This is the '-s' option of standard gzip. Here you can specify an optional suffix to use instead of '.gz'. If you are using the standard suffixes; don't check this option.

If you have to expand files with a suffix different of ".gz", ".z", ".Z", ".taz", ".tgz", "-gz", "-z" and "_z" often, (for instance, one member .zip files); you should check the 'only when decompressing' option as well.

Note: Setting custom suffix to '.Z' won't force MacGzip to create Unix 'compress' files; but gzip files with .Z suffix, which can be confusing.

* Compression level:

This is the '-[1-9]' option. The higher level, the slower and better compression. Compression level does not affect to decompression.

* Force overwrite:

This is the '-f' option. If you set it, MacGzip will overwrite files or empty folders if their names are the same of an output file.

* Always save/restore name & date:

This is the '-N' option:
When compressing, always save the original file name and time stamp; this is the default. When decompressing, restore the original file name and time stamp if present. This option is useful on systems which have a limit on file name length or when the time stamp has been lost after a file transfer.


- If the original name contains illegal characters, MacGzip will replace them regardless if you check this option or not.

* Never save/restore name & date:

This is the '-n' option:
When compressing, do not save the original file name and time stamp by default. (The original name is always saved if the name had to be truncated.) When decompressing, do not restore the original file name if present (remove only the gzip suffix from the compressed file name) and do not restore the original time stamp if present (copy it from the compressed file). This option is the default when decompressing.

* Drop folder options:

-r option. You can drop folders on MacGzip; but in this version, you can't have more than 512 files in the queue.

- MacGzip options:

You can use MacGzip as a pure Unix gzip or as a Macintosh compressor.

In the first case, you may turn off all the MacBinary options (for compress and decompress preferences); but anyway you should use some suffix mapping to treat text files in a proper way. (well, if you always use binary mode, you always can use an end-of-line converter; but it
will take you more time...).

If you know you will never transfer a .gz file to any non-MacOS machine; you can use always MacBinary. (anyway, there are also MacBinary translators for other machines; in unix you can use 'capit', from Columbia AppleTalk Package)

Please, read the document 'File formats' for more info.

The default settings will try to use Internet Config to decide when to use one format or other. Default settings for Internet Config map many suffixes of files in which only the data fork is relevant to 'Macintosh file', just to make sure you don't loose things like Finder custom icons and things like that.

If you are planning to transfer gzip files to another OS, and you want to use IC, make sure you set all the mappings properly.

In decompression preferences, it is safe to check the 'Always try MacBinary'. (but can be a little slower). MacGzip checks the MacBinary II+ crc for the first 128 bytes of the file, so it will use MacBinary only for actual MacBinary gziped files.
(In the progress window, you may notice that for short files the string mode is always 'MBII' even for binary or ascii files; this is because the input file was so short so MacGzip can't know which mode to use till it have read the entire file; anyway the correct mode is used)

Note: MacGzip MacBinary mode doesn't save/restore Finder comments. (people uses them, anyway?)

The mode (and the compress/decompress) selection is made according your preferences:
First Drag&Drop keys -if you checked this option- or menu selection; then automatic selections, and as last resource, the default mode (operation).

Note: If you want to use Fetch prefs for suffix mapping, make sure you check the corresponding option in MacGzip decompress preferences (it is not the default for MacGzip 1.1). (Fetch 3.0 uses IC, too).

The 'use ASCII for TEXT files' option is safe unless you have some wicked programs which make binary files with 'TEXT' signature. (like some communications software). Anyway IC should be enaugh to handle this...

The 'Beep when done' preference has a side effect. If it is checked, an audible 'click' will let you know MacGzip has accepted the file(s) you drop on it (and so you can release the modifier keys...)

* Signatures:

Files compressed with gzip haven't any information about the kind of document of the original file; so to decompress them MacGzip has to guess it. Sometimes this can be done by looking at the suffix; when this fails, it will use these.

You can find more information about this in the 'Suffix Mapping' document.

* More Help:

In the preferences dialog there is a little check box with a tiny balloon icon. Check this to see what every item on the dialog means.

You can read the rest of the documentation to find out about file types, transmision modes, suffix mapping, the meaning of life and even more.

* Using Macgzip

Select your files/folders and drop them on the MacGzip icon.

The 'cancel' button (or cmd-period) interrupts the process and the partial output file is erased.

If you want to cancel all pending work, select 'Quit' (or cmd-Q) in File menu. (this is a safe exit, you should never force exit using cmd-opt-esc except as a last resort)

Once MacGzip is working on a file, you can't use the File menus to submit new work;
but you can drop files/folders from the Finder onto the MacGzip icon or use the Standard Apple Events.

These are the modifier keys you can use:

a: Force ASCII (text) mode
b: Force Binary (raw) mode
m: Force MacBinary mode
opt: Force compression
shift: Force decompression
ctrl: Force 'Prompt for destination' (useful for Read Only media)

(You don't need to remember this, you can read it at any time in the MacGzip Finder Help Balloon)

* About types & creators

I have used the following file Types:

suffix type creator
.gz Gzip Gzip gziped
.Z ZIVU Gzip compressed (from maccompress)
.z pZIP Gzip pkziped (from UnZip 2.0.1)

Anyway, read GNU's gzip.doc to find out about formats.

When you download a file from a non-mac host, the program that you are using to download must assign it two flags: File Type and File Creator. These are two four character words that the Mac uses to know what icon they must have, what application must be opened when you make a double click on it, and if a 'open file' dialog should show the file or not.

So, you should use a downloading application with a "suffix mapping" menu or preference, or at least, a drag&drop file typer. With this version of MacGzip, you don't need to use the correct type, but is a good idea to keep your files well typed.

If you want MacGzip to set the correct types but you don't use Fetch, you can find a 'Fetch Prefs' file in the 'Suffix Mapping'. You can copy it to your Preferences folder (in your System folder); and if you want to add suffixes, you can edit it with ResEdit or other resource editor (there is a template included).

Or you can use Internet Config, available from

* Warranty & so

The guarantee is directly proportional to the price of the application: NONE. (OK, if you loose a very important file with 2.3 Mb of data, let me know it and I will send you a few words of condolence).

* Year 2000 Compilance

MacGzip is as Y2K compilant as MacOS. (well, in fact, dates in .gz files are stored in unix 32 bit wide format, this mean tinks can go wrong beyond 2038, see <URL:>)

MacGzip was Y2K tested by the simple procedure of making it work on a Macintosh with date manually set to beyond year 2000, and everything was OK.

* Thanks to:

Jean-loup Gailly <> for gzip
Erling Johansen <> for the port to PPC and Posix lib used in 03bx
Timothy Murphy <> for Posix lib used in the first versions.
Quinn "The Eskimo" <> and
Peter N Lewis <> for Internet Config Prog. Kit
Peter N Lewis (again) for MacBinary II+ stuff
Todd Clements ( for DialogControls code
Steve Falkenburg -- MacDTS for CustomGetFolder for SpinCursors code
Greg Robbins for Prefs code
C.K. Haun (Apple DTS) for Movable Modal code
Color Alysoft Solutions <> for Color Progress bar code
Bryan Stearns (Apple DTS) for Pop Up Menus code
Dave Rubinic for Easy Errors 1.0 resources
Jesse Carneiro ( for click sound
Luke Collie <> for helping with documentation
Lloyd Chambers (MacCompress) for Icons idea
David "ELEE74L" Alten <""> for icons improvement
All other people whose source code I used 'for documentation'
And people who sent bug reports

At last, thanks to myself
for being such nice company.

Latest about MacGzip:

* REWARD 0.000.000 $
BUGS (dead or alive)

A mí me gusta dormir
hasta el medio día y
aullar a la luna
y a las estrellas y...

...Y entrar y salir
de mi chabolo sin
ninguna explicación que dar
Sí, a mí me gusta asi.

Claro que algunas noches
no puedo dormir
Entonces me ducho
y si quema mucho

me da el arrechucho
y salgo a por tí.

Y... ?Qué mas me gusta a mí?
!Ah, sí! la pintura y...
Y más si es de labios,
Si, a mí me gusta así
?Y qué era lo otro? !Ah, sí!
Lo que más me gusta a mí
...?Te lo digo en casa
o te lo digo aquí?

Los Enemigos

Original file name: README - converted on Monday, 20 September 1999, 22:36

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