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MKUZIP(8)		  BSD System Manager's Manual		     MKUZIP(8)

     mkuzip -- compress	disk image for use with	geom_uzip(4) class

     mkuzip [-v] [-o outfile] [-s cluster_size]	infile

     The mkuzip	utility	compresses a disk image	file in	such a way that	the
     geom_uzip(4) class	will be	able to	decompress resulting image in run-
     time.  This allows	for significant	reduction of size of disk image	at the
     expense of	some CPU time required to decompress the data each time	it is
     read.  Internally,	operation is done in two phases	as follows:

     1.	  An infile image is split into	clusters and each cluster compressed
	  using	zlib(3).

     2.	  Resulting set	of compressed clusters along with headers allowing to
	  independently	locate each individual cluster is written into output

     The options are:

     -o	outfile
	     Name the output file outfile.  The	default	is to use the input
	     name with the suffix .uzip.

     -s	cluster_size
	     Use cluster_size as the size of chunks the	file being split up
	     into.  Default value is 16384 bytes.  The cluster_size should be
	     a multiple	of 512 bytes.

     -v	     Display verbose messages.

     Compression ratio largely depends on the cluster size used.  For large
     cluster sizes (16K	and higher), typical compression ratios	are only 1-2%
     less than those achieved with the gzip(1) utlity.	However, it should be
     kept in mind that larger cluster sizes lead to higher overhead in the
     geom_uzip(4) class, as the	class has to decompress	the whole cluster even
     if	only several bytes from	that cluster have to be	read.

     The mkuzip	inserts	tiny shell script at the beginning of the generated
     image, which makes	it possible to "run" the image just like any other
     shell script.  This script	tries to load geom_uzip(4) class if it is not
     loaded, configure image as	an md(4) disk device using mdconfig(8) util-
     ity, and automatically mount it using mount_cd9660(8) utility to the
     mount point provided as a first argument.

     gzip(1), zlib(3), geom(4),	geom_uzip(4), md(4), mdconfig(8),

     The mkuzip	utility	exits 0	on success, and	>0 if an error occurs.

     Maxim Sobolev <>

BSD			      September	10, 2004			   BSD


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