The utility
creates a file system image into
image-file
from the directory tree
directory
No special devices or privileges are required to perform this task.
The options are as follows:
-B byte-order
Set the byte order of the image to
byte-order
Valid byte orders are
`4321'
,
`big'
,
or
`be'
for big endian, and
`1234'
,
`little'
,
or
`le'
for little endian.
Some file systems may have a fixed byte order; in those cases this
argument will be ignored.
-b free-blocks
Ensure that a minimum of
free-blocks
free blocks exist in the image.
An optional
`%'
suffix may be provided to indicate that
free-blocks
indicates a percentage of the calculated image size.
-d debug-mask
Enable various levels of debugging, depending upon which bits are
set in
debug-mask
XXX: document these
-F specfile
Use
specfile
as an
mtree(8)
`specfile'
specification.
If a specfile entry exists in the underlying file system, its
permissions and modification time will be used unless specifically
overridden by the specfile.
An error will be raised if the type of entry in the specfile
conflicts with that of an existing entry.
In the opposite case (where a specfile entry does not have an entry
in the underlying file system) the following occurs:
If the specfile entry is marked
optional
the specfile entry is ignored.
Otherwise, the entry will be created in the image, and it is
necessary to specify at least the following parameters in the
specfile:
typemodegname
or
gid
and
uname
or
uiddevice
(in the case of block or character devices), and
link
(in the case of symbolic links).
If
time
isn't provided, the current time will be used.
If
flags
isn't provided, the current file flags will be used.
Missing regular file entries will be created as zero-length files.
-f free-files
Ensure that a minimum of
free-files
free files (inodes) exist in the image.
An optional
`%'
suffix may be provided to indicate that
free-files
indicates a percentage of the calculated image size.
-M minimum-size
Set the minimum size of the file system image to
minimum-size
-m maximum-size
Set the maximum size of the file system image to
maximum-size
An error will be raised if the target file system needs to be larger
than this to accommodate the provided directory tree.
-N dbdir
Use the user database text file
master.passwd
and group database text file
group
from
dbdir
rather than using the results from the system's
getpwnam(3)
and
getgrnam(3)
(and related) library calls.
-o fs-options
Set file system specific options.
fs-options
is a comma separated list of options.
Valid file system specific options are detailed below.
-S sector-size
Set the file system sector size to
sector-size
Defaults to 512.
-s image-size
Set the size of the file system image to
image-size
-t fs-type
Create an
fs-type
file system image.
The following file system types are supported:
ffs
BSD fast file system (default).
cd9660
ISO 9660 file system.
-x
Exclude file system nodes not explicitly listed in the specfile.
Where sizes are specified, a decimal number of bytes is expected.
Two or more numbers may be separated by an
``x''
to indicate a product.
Each number may have one of the following optional suffixes:
b
Block; multiply by 512
k
Kibi; multiply by 1024 (1 KiB)
m
Mebi; multiply by 1048576 (1 MiB)
g
Gibi; multiply by 1073741824 (1 GiB)
t
Tebi; multiply by 1099511627776 (1 TiB)
w
Word; multiply by the number of bytes in an integer
FFS-specific options
ffs
images have ffs-specific optional parameters that may be provided.
Each of the options consists of a keyword, an equal sign
(`='
)
and a value.
The following keywords are supported:
avgfilesize
Expected average file size.
avgfpdir
Expected number of files per directory.
bsize
Block size.
density
Bytes per inode.
fsize
Fragment size.
maxbpg
Maximum blocks per file in a cylinder group.
minfree
Minimum % free.
optimization
Optimization preference; one of
`space'
or
`time'
extent
Maximum extent size.
maxbpcg
Maximum total number of blocks in a cylinder group.
version
UFS version.
1 for FFS (default), 2 for UFS2.
CD9660-specific options
cd9660
images have ISO9660-specific optional parameters that may be
provided.
The arguments consist of a keyword and, optionally, an equal sign
(`='
)
and a value.
The following keywords are supported:
allow-deep-trees
Allow the directory structure to exceed the maximum specified in
the spec.
allow-max-name
Allow 37 instead of 33 characters for filenames by omitting the
version id.
allow-multidot
Allow multiple dots in a filename.
applicationid
Application ID of the image.
archimedes
Use the
`ARCHIMEDES'
extension to encode
RISC OS
metadata.
boot-info-table
Write a legacy 56-byte table at offset 8 into the boot image
(see below)
boot-load-segment
Set load segment for the boot image.
bootimage
Filename of a boot image in the format
``sysid;filename''
where
``sysid''
is one of
`i386'
,
`mac68k'
,
`macppc'
,
or
`powerpc'
creation-date
Override PVD creation date.
effective-date
Override PVD effective date.
expiration-date
Override PVD expiration date.
generic-bootimage
Load a generic boot image into the first 32K of the cd9660 image.
hard-disk-boot
Boot image is a hard disk image.
hide-rr-moved
Assign the
RR_MOVED
directory a rock ridge name of the empty string instead of the default
.rr_moved
keep-bad-images
Don't throw away images whose write was aborted due to an error.
For debugging purposes.
label
Label name of the image.
modification-date
Override PVD modification date.
no-boot
Boot image is not bootable.
no-emul-boot
Boot image is a
``no emulation''
ElTorito image.
no-trailing-padding
Do not pad the image (apparently Linux needs the padding).
omit-trailing-period
Violate the standard, do not append a trailing period to
filenames without an extension.
preparer
Preparer ID of the image.
publisher
Publisher ID of the image.
rockridge
Use RockRidge extensions (for longer filenames, etc.).
rr-squash
Force uid 0, gid 0, and rationalised permission bits for RockRidge entries.
volumeid
Volume set identifier of the image.
The
boot-info-table
currently consists of the following fields (all 7.3.1 numbers),
offsets relative to the boot image:
0
8 bytes: kept as is, not part of checksum
8
LBA of PVD
12
LBA of boot image
16
Size in bytes of boot image
20
32-bit additive sum of all 32-bit words of boot image
24
40 reserved bytes (MBZ)
64
Begin of checksummed data, kept as is
Dates (to override) are in 8.4.26.1 format
(YYYYmmddHHMMSS00
)
and Universal Time, i.e. with zero offset from Greenwich Mean Time.
Support for overriding PVD dates and the boot info table was added in
MirOS
AUTHORS
An Luke Mewburn
Aq lukem@NetBSD.org
(original program)
An Daniel Watt ,
An Walter Deignan ,
An Ryan Gabrys ,
An Alan Perez-Rathke ,
An Ram Vedam
(cd9660 support)
An Thorsten Glaser Aq tg@mirbsd.org
CAVEATS
may be limited to images less than 2 GiB in size
due to internal use of the long type.