SYNOPSIS

[-x ] [-B byte-order ] [-b free-blocks ] [-d debug-mask ] [-F specfile ] [-f free-files ] [-M minimum-size ] [-m maximum-size ] [-N userdb-dir ] [-o fs-options ] [-S sector-size ] [-s image-size ] [-t fs-type ] [-T maximum-time ] image-file directory

DESCRIPTION

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: type mode gname or gid and uname or uid device (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.

-T maximum-time

Clamp superblock and file timestamps to maximum-time seconds since the Epoch.

-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.

HISTORY

The utility appeared in Nx 1.6 .

Support for overriding PVD dates and the boot info table was added in MirOS

AUTHORS

An Luke Mewburn Aq [email protected] (original program) An Daniel Watt , An Walter Deignan , An Ryan Gabrys , An Alan Perez-Rathke , An Ram Vedam (cd9660 support) An Thorsten Glaser Aq [email protected]

CAVEATS

may be limited to images less than 2 GiB in size due to internal use of the long type.