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I'm using mkfs.hfsplus to create a HFS+ volume on Linux, but I want to compress it using Apple's UDIF format. It looks like I should be able to use bzip2 to do this, but I can't really tell how.

Any ideas on how I can create a read-only, UDIF compressed HFS+ volume on Linux?

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Looks like this was cross posted to SuperUser also... – Josh Jan 16 '11 at 16:10
But why? What is the larger context? – ewwhite Oct 18 '12 at 12:10

Don't know about UDIF, but HFS+ does support transparent compression. There is an opensource tool called afsctool that will be able to convert your files into compressed state. Not sure whether the tool will work on Linux, as I think it uses build-in Mac OS X api.

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You might want to look at the source of FreeDMG, an OS X utility which can convert DMGs to many different formats. You need to make sure the image type is UDBZ (UDIF bzip2 compressed)

You may also want to check out the dmg2img tool, the source here may provide some clues.

Of course your best bet is to use a Darwin / OS X system to do this. Why do you need to use Linux? If you can find a way to do this under Darwin you'll make things a lot easier on yourself.

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