cloop or zisofs or a better way?

Dan Nelson dnelson at
Sat Feb 4 18:09:36 PST 2006

In the last episode (Feb 04), Xn Nooby said:
> I'm looking for a way to compress about 20GB of ASCII data in to a
> read-only file that is as small as possible.  I found 'cloop' and
> 'zisofs', though I could not find anything on the net where FreeBSD
> people were using them. They are in the ports tree, so I figure
> somebody is.  Is there a preferred way under FreeBSD of doing this? 
> I've heard of people using "loopback" connections, and I guess that's
> what cloop is.  Or maybe there is a way to mount a tgz file? I'm
> using FreeBSD 6.x.
> Also, is there a crossplatform way of doing this?  For example, if I
> had a compressed volume, would I be able to read it under Linux and
> maybe Windows?  I dont really need crossplatform, but was curious.

You can also use the mkuzip command (and the geom_uzip kernel module)
in the base system, which generates the same file format as Linux cloop
files but is much more memory-efficient than cloop's
create_compressed_fs program.  I don't think there is any Windows
support for mounting compressed filesystem images (I can't even find
Windows tools for mounting filesystem images in general apart from
daemontools which only does ISO images).

	Dan Nelson
	dnelson at

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