[SVass]

How do I do it. Somewhere I read that ditto will work. How do I do that? Or is there a simpler way?
sam

[Hal Itosis]

Double-click (and OSX should expand it for you).

<edit>

As far as the CLI goes, looks like this should also work:
ditto -x /path/to/archive.cpgz /path/to/target/folder/

[SVass]

Originally Posted by Hal Itosis 

Double-click (and OSX should expand it for you).

<edit>

As far as the CLI goes, looks like this should also work:
ditto -x /path/to/archive.cpgz /path/to/target/folder/

Thanks for the advice. I found that Stuffit Expander will work and No, OSX no longer works. I have Snow Leopard latest and my spouse's machine has Leopard and my old desktop has Tiger and double-clicking does not work on this new file type from Microsoft.

[CharlesS]

That would surprise me, since CPGZ has long been the default format that Archive Utility uses to compress files (and it's been the format that installer packages use to compress file contents for as long as OS X has existed).

Could you perhaps create one of these files that OS X supposedly won't expand and post it online?

[Hal Itosis]

Originally Posted by SVass 

Thanks for the advice. I found that Stuffit Expander will work and No, OSX no longer works. I have Snow Leopard latest and my spouse's machine has Leopard and my old desktop has Tiger and double-clicking does not work on this new file type from Microsoft.

A "cpgz" file is a gzip-compressed cpio (Unix) archive.

With assistance from teh google, i found...

• The original cpio utility was written by Dick Haight while working in AT&T's Unix Support Group. It appeared in 1977 as part of PWB/UNIX 1.0, the "Programmer's Work Bench" derived from Version 6 AT&T UNIX that was used internally at AT&T.
  .
• The gzip (GNU zip) format was designed by Jean-Loup Gailly (around the mid-90's) and interestingly enough, the associated RFC seems to be authored by an Aladdin engineer.

So basically, cpgz is most definitely *not* some "new file type from Microsoft."

Note too how these (generic) info pages all mention Mac OS X:
File Extension .CPGZ Details
CPGZ File Extension - Open .CPGZ files
Description of CPGZ file extension

You didn't say what exactly does happen when double-clicking. [i.e., did it seem that the OS even *tried* to expand it? How about ditto -x from the command line? Did that fail as well?] Point being: the fact that double-clicking failed does not necessarily mean the OS can't expand .cpgz files -- rather, there may be something strange about that file which prevented the Finder/LaunchServices team from handing it off to the CoreServices Archive Utility.

[SVass]

When I double click on a "new" zip file from a Windows Excel file (test.zip) , I get a file with a name like test.zip.cpzg
If I double click on that, I get a file named test2.zip
This happened both under Leopard on a Powerbook and Snow Leopard on my MacBook Pro.
Tiger claimed that the operation was "illegal". I am assuming that the file was created in a new version of Excel under Windows 7.
The actual file is available at
Super GW Similariity based upon half-identical segment count(20).zip - File Shared from Box.net - Free Online File Storage
Note that, as I said, Stuffit Expander worked.
sam

[CharlesS]

Ah, that makes sense. The ZIP file is probably in a format that OS X doesn't know how to read (the built-in ZIP functionality is actually somewhat limited). Perhaps it is a Zip64 archive, a really old archive from the 90s, or uses an unsupported compression type. What's happening is: the default application for .zip files is set to Archive Utility, so the Finder attempts to open the file with AU when you double-click on it. However, Archive Utility is not recognizing it as an archive it can read, probably due to one of the aforementioned reasons, and thus it's treating it as an uncompressed file - and when it gets one of those, Archive Utility compresses it. And as I mentioned before, Archive Utility's default format is, for some reason, CPGZ.

So, you're not getting CPGZ files from Windows - Archive Utility is just making those when it encounters a ZIP file that it can't read. Unfortunately, I'm not at my computer right now (public machine in a library), so I can't download and look at the file to see what the reason for this is. It would be kind of interesting to see if the file opens in Pacifist, though - if it doesn't, then that's new functionality for me to add at some point.

[Art Vandelay]

The file decompressed just fine on Snow Leopard.

[Hal Itosis]

Originally Posted by Art Vandelay 

The file decompressed just fine on Snow Leopard.

And here in 10.5.8 (on a ppc G4) as well. Got a folder with 2 items:
Read About Sheet.txt
Super GW Similariity based upon half-identical segment count(20).xls

Only one "expansion" occurred.

[SVass]

Sehr interessant.
I downloaded again and it works just as you said. I still have the old file and it doesn't work except in Stuffit.
Weird.
sam

[CharlesS]

Huh. Maybe the file on your hard disk got damaged somehow.