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7zip for classic Mac OS?


Well-known member
Is there a 7-zip supporting compressor or decompressor for the classic OS available or needs it to be written first?

I found p7zip and stuffit for OS X only.

For interested people using vintage macs

A low memory LZMA decompressing source is at the coreboot project repo to find.



Well-known member
AFAIK, the 7-zip format (.7z) was only made available when the 7-Zip program in Windows was introduced. I doubt that there's anything available that supports that compression format on anything released earlier than the release of 7-Zip itself.


Dog Cow

Well-known member
7zip = the devil's compression format of choice.

I downloaded some file in 7zip a month or few ago, not knowing what it was, then was annoyed when I discovered I had no program on my Mac to decompress it.


Dennis Nedry

Well-known member
It's open-source, so it could theoretically be gotten to build somehow on a classic Mac.

Your best bet is probably to decompress on a modern Mac or PC and then transfer the decompressed stuff over.



Computer Janitor
Staff member
Ah, my bad. There doesnt seem to be one. if the unix version doesnt need too man libraried you /might/ be able to make a sioux version.




Leader, Tactical Ops Unit
Unarchiver doesn't support all the features of 7zips anyway, like passworded archives. Better than having to use command line 7z for everything, though.



Well-known member
I come to the conclusion that 7z decompression is only possible in OSX.

LZMA is a open source algorithm so its not impossible to write a archiver even for system 6-9.