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A few minor corrections to the mkuzip.8 man page.

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PR:		92576
Submitted by:	Stefan Bethke
This commit is contained in:
Maxim Sobolev 2006-03-17 20:48:10 +00:00
parent 2f60f02dc9
commit d3ff297263
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=156818
1 changed files with 24 additions and 25 deletions
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49
usr.bin/mkuzip/mkuzip.8
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@ -24,37 +24,36 @@ class
.Sh DESCRIPTION
The
.Nm
utility compresses a disk image file in such a way that the
utility compresses a disk image file so that the
.Xr 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
class will be able to decompress the resulting image at run-time.
This allows for a 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:
.Nm
works in two phases:
.Bl -enum
.It
An
.Ar infile
image is split into clusters and each cluster compressed using
image is split into clusters; each cluster is compressed using
.Xr zlib 3 .
.It
Resulting set of compressed clusters along with headers allowing to
independently locate each individual cluster is written into
output file.
The resulting set of compressed clusters along with headers that allow
locating each individual cluster is written to the output file.
.El
.Pp
The options are:
.Bl -tag -width indent
.It Fl o Ar outfile
Name the output file
Name of the output file
.Ar outfile .
The default is to use the input name with the suffix
.Pa .uzip .
.It Fl s Ar cluster_size
Use
Split the image into clusters of
.Ar cluster_size
as the size of chunks the file being split up into.
Default value is 16384 bytes.
bytes, 16384 bytes by default.
The
.Ar cluster_size
should be a multiple of 512 bytes.
@ -62,33 +61,33 @@ should be a multiple of 512 bytes.
Display verbose messages.
.El
.Sh NOTES
Compression ratio largely depends on the cluster size used.
The compression ratio largely depends on the cluster size used.
.\" The following two sentences are unclear: how can gzip(1) be
.\" used in a comparable fashion, and wouldn't a gzip-compressed
.\" image suffer from larger cluster sizes as well?
For large cluster sizes (16K and higher), typical compression ratios
are only 1-2% less than those achieved with the
.Xr gzip 1
utlity.
are only 1-2% less than those achieved with
.Xr gzip 1 .
However, it should be kept in mind that larger cluster
sizes lead to higher overhead in the
.Xr 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.
only a few bytes from that cluster have to be read.
.Pp
The
.Nm
inserts tiny shell script at the beginning of the generated image,
inserts a short shell script at the beginning of the generated image,
which makes it possible to
.Dq run
the image just like any other shell script.
This script tries
to load
The script tries to load the
.Xr geom_uzip 4
class if it is not loaded, configure image as an
class if it is not loaded, configure the image as an
.Xr md 4
disk device using
.Xr mdconfig 8
utility, and automatically mount it using
.Xr mdconfig 8 ,
and automatically mount it using
.Xr mount_cd9660 8
utility to the mount point provided as a first argument.
on the mount point provided as the first argument to the script.
.Sh EXIT STATUS
.Ex -std
.Sh SEE ALSO