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-rw-r--r--usr.bin/mkuzip/mkuzip.848
1 files changed, 32 insertions, 16 deletions
diff --git a/usr.bin/mkuzip/mkuzip.8 b/usr.bin/mkuzip/mkuzip.8
index 277faf2..bc2d9c50 100644
--- a/usr.bin/mkuzip/mkuzip.8
+++ b/usr.bin/mkuzip/mkuzip.8
@@ -12,9 +12,9 @@
.Os
.Sh NAME
.Nm mkuzip
-.Nd compress a
+.Nd compress disk image for use with
.Xr geom_uzip 4
-image
+class
.Sh SYNOPSIS
.Nm
.Op Fl v
@@ -26,11 +26,11 @@ The
.Nm
utility compresses a disk image file in such a way that the
.Xr geom_uzip 4
-class will be able to decompress resulting image in run-time
-when it loaded into memory. This allows for significant reduction
-of memory footprint of memory-based filesystem 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:
+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:
.Bl -enum
.It
An
@@ -38,7 +38,7 @@ An
image is split into clusters and each cluster compressed using
.Xr zlib 3 .
.It
-Resulting set of clusters along with headers allowing to
+Resulting set of compressed clusters along with headers allowing to
independently locate each individual cluster is written into
output file.
.El
@@ -54,30 +54,46 @@ The default is to use the input name with the suffix
Use
.Ar cluster_size
as the size of chunks the file being split up into. Default value
-is 16K. The
+is 16384 bytes. The
.Ar cluster_size
-should be multiple of block size of the
-.Xr geom_uzip 4
-device (usually 512 bytes).
+should be multiple of 512 bytes.
.It Fl v
Display verbose messages.
.El
.Sh NOTES
Compression ratio largely depends on the cluster size used. For
-large cluster sizes of (16K and higher) typical compression ratios
+large cluster sizes (16K and higher) typical compression ratios
are only 1-2% less than those achieved with the
.Xr gzip 1
utlity. 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
-literally only several bytes from that cluster have to be read.
+only several bytes from that cluster have to be read.
+.Pp
+The
+.Nm
+inserts tiny shell script at the beginning of the generated image,
+which makes it possible to
+.Qq run
+the image just like any other shell script. This script tries
+to load
+.Xr geom_uzip 4
+class if it is not loaded, configure image as a
+.Xr md 4
+disk device using
+.Xr mdconfig 8
+utility and automatically mount it using
+.Xr mount_cd9660 8
+utility to the mount point provided as a first argument.
.Sh SEE ALSO
.Xr gzip 1 ,
.Xr zlib 3 ,
.Xr geom_uzip 4 ,
-.Xr boot 8 ,
-.Xr loader 8
+.Xr geom 4 ,
+.Xr md 4 ,
+.Xr mdconfig 8 ,
+.Xr mount_cd9660 8 .
.Sh DIAGNOSTICS
Exit status is 0 on success and >0 on error.
.Sh AUTHORS
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