1GENROMFS(8) System Manager's Manual GENROMFS(8)
2
6 genromfs - create a romfs image
7
9 genromfs -f device [ -d source ] [ -V label ] [ -a alignment ] [ -A
10 alignment,pattern ] [ -x pattern ] [ -v ]
11
13 genromfs is used to create a romfs file system image, usually directly
14 on a block device, or for test purposes, in a plain file. It is the
15 mkfs equivalent of other filesystems.
16 genromfs will scan the current directory and its subdirectories, build
18 a romfs image from the files found, and output it to the file or device
19 you specified.
20 During scanning, it recognizes a special notation. If a file begins
22 with the @ sign (and is empty otherwise), it refers to a device special
23 node in the format: @name,type,major,minor. type can be b for block
24 devices, c for character devices, and p for fifos. The linux virtual
25 console 1 can thus be included as a file with the name: @tty1,c,4,1
26
29 -f output
30 Specifies the file to output the image to. This option is
31 required.
32 -d source
34 Use the specified directory as the source, not the current
35 directory.
36 -V label
38 Build the image with the specified volume label. Currently it
39 is not used by the kernel, but it will be recorded in the image.
40 -a alignment
42 Align regular files to a larger boundary. genromfs will align
43 data of each regular file in the resulting image to the speci‐
44 fied alignment, while keeping the image compatible with the
45 original romfs definition (by adding pad bytes between last node
46 before the file and file's header). By default, genromfs will
47 guarantee only an alignment of 16 bytes.
48 -A alignment,pattern
50 Align objects matching shell wildcard pattern to alignment
51 bytes. If one object matches more patterns, then the highest
52 alignment is chosen. Alignment has to be a power of two. Pat‐
53 terns either don't contain any slashes, in which case files
54 matching those patterns are matched in all directories, or start
55 with a leading slash, in which case they are matched against
56 absolute paths inside of the romfs filesystem (that is, as if
57 you chrooted into the rom filesystem).
58 -x pattern
60 Allow to exclude files that match a pattern. It's useful to
61 exclude CVS directories and backup files (ending in a '~').
62 -v Verbose operation, genromfs will print each file which is
64 included in the image, along with its offset.
65
67 genromfs -d root -f /dev/fd0 -V 'Secret labs install disk'
68 All files in the root directory will be written to /dev/fd0 as a new
70 romfs filesystem image.
71 genromfs -d root -f /dev/fd0 -A 2048,/.. -A '4096,*.boot' -a 512 -V 'Bootable floppy'
73 Generate the image and place file data of all regular files on 512
75 bytes boundaries or on 4K boundaries, if they have the .boot extension.
76 Additionally, align the romfs header of the '..' entry in the root
77 directory on a 2K boundary. Effectively, this makes sure that the
78 romfs image uses the least possible space in the first 2048 bytes.
79 You can use the generated image (if you have the romfs module loaded,
81 or compiled into the kernel) via:
82 mount -t romfs /dev/fd0 /mnt
84
87 This manual page was initially written by Christoph Lameter <clame‐
88 ter@debian.org>, for the Debian GNU/Linux system.
89
91 mkfs(8), mount(8), mkisofs(8)
92Version 0.5.2 Jun 2007 GENROMFS(8)