"-x, --starting-image image" Use this image as a starting point.
"-d, --root directory[:path]" Add the given directory and contents at a particular path (by default the root).
"-D, --devtable spec-file[:path]" Use spec-file to specify inodes to be added, at the given path (by default the root), including files, directories and special files like devices. If the specified files are already present in the image, their ownership and permission modes will be adjusted accordingly. Furthermore, you can use a single table entry to create many devices with a range of minor numbers (see examples below). All specified inodes receive the mtime of spec-file itself.
"-b, --size-in-blocks blocks" Size of the image in blocks.
"-N, --number-of-inodes inodes" Maximum number of inodes.
"-i, --bytes-per-inode ratio" Used to calculate the maximum number of inodes from the available blocks.
"-m, --reserved-percentage" Number of reserved blocks as a percentage of size. Reserving 0 blocks will prevent creation of the "lost+found" directory.
"-g, --block-map path" Generate a block map file for this path.
"-e, --fill-value value" Fill unallocated blocks with value.
"-z, --allow-holes" Make files with holes.
"-f, --faketime" Use a timestamp of 0 for inode and filesystem creation, instead of the present. Useful for testing.
"-q, --squash" Squash permissions and owners (same as -P -U).
"-U, --squash-uids" Squash ownership of inodes added using the -d option, making them all owned by root:root.
"-P, --squash-perms" Squash permissions of inodes added using the -d option. Analogous to "umask 077".
"-v, --verbose" Print resulting filesystem structure.
"-V, --version" Print genext2fs version.
"-h, --help" Display help.
f A regular file d Directory c Character special device file b Block special device file p Fifo (named pipe)uid is the user id for the target file, gid is the group id for the target file. The rest of the entries (major, minor, etc) apply only to device special files. An example device file follows:
# name type mode uid gid major minor start inc count /dev d 755 0 0 - - - - - /dev/mem c 640 0 0 1 1 0 0 - /dev/tty c 666 0 0 5 0 0 0 - /dev/tty c 666 0 0 4 0 0 1 6 /dev/loop b 640 0 0 7 0 0 1 2 /dev/hda b 640 0 0 3 0 0 0 - /dev/hda b 640 0 0 3 1 1 1 16 /dev/log s 666 0 0 - - - - -This device table creates the /dev directory, a character device node /dev/mem (major 1, minor 1), and also creates /dev/tty, /dev/tty[0-5], /dev/loop[0-1], /dev/hda, /dev/hda1 to /dev/hda15 and /dev/log socket.