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diff --git a/genext2fs.8 b/genext2fs.8 new file mode 100644 index 0000000..53961a2 --- /dev/null +++ b/genext2fs.8 @@ -0,0 +1,172 @@ +.\" Hey, EMACS: -*- nroff -*- +.\" First parameter, NAME, should be all caps +.\" Second parameter, SECTION, should be 1-8, maybe w/ subsection +.\" other parameters are allowed: see man(7), man(1) +.TH GENEXT2FS 8 "August 19, 2006" +.\" Please adjust this date whenever revising the manpage. +.\" +.\" Some roff macros, for reference: +.\" .nh disable hyphenation +.\" .hy enable hyphenation +.\" .ad l left justify +.\" .ad b justify to both left and right margins +.\" .nf disable filling +.\" .fi enable filling +.\" .br insert line break +.\" .sp <n> insert n+1 empty lines +.\" for manpage-specific macros, see man(7) +.SH NAME +genext2fs \- ext2 filesystem generator for embedded systems +.SH SYNOPSIS +.B genext2fs +.RI "[ options ] [ output\-image ]" +.SH DESCRIPTION +\fBgenext2fs\fP generates an ext2 filesystem +as a normal (non-root) user. It does not require you to mount +the image file to copy files on it, nor does it require that +you become the superuser to make device nodes. + +The filesystem image is created in the file \fIoutput-image\fP. If not +specified, it is sent to stdout. + +By default, the maximum number of inodes in the filesystem is the minimum +number required to accommodate the initial contents. +In this way, a minimal filesystem (typically read-only) can be created with +minimal free inodes. +If required, free inodes can be added by passing the relevant options. +The filesystem image size in blocks can be minimised by trial and error. +.SH OPTIONS +.TP +.BI "\-x, \-\-starting\-image image" +Use this image as a starting point. +.TP +.BI "\-d, \-\-root directory[:path]" +Add the given directory and contents at a particular path (by default +the root). +.TP +.BI "\-D, \-\-devtable spec\-file[:path]" +Use \fBspec-file\fP 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 \fBspec-file\fP itself. +.TP +.BI "\-b, \-\-size\-in\-blocks blocks" +Size of the image in blocks. +.TP +.BI "\-N, \-\-number\-of\-inodes inodes" +Maximum number of inodes. +.TP +.BI "\-i, \-\-bytes\-per\-inode ratio" +Used to calculate the maximum number of inodes from the available blocks. +.TP +.BI "\-m, \-\-reserved\-percentage" +Number of reserved blocks as a percentage of size. Reserving 0 blocks will prevent creation of the "lost+found" directory. +.TP +.BI "\-g, \-\-block\-map path" +Generate a block map file for this path. +.TP +.BI "\-e, \-\-fill\-value value" +Fill unallocated blocks with value. +.TP +.BI "\-z, \-\-allow\-holes" +Make files with holes. +.TP +.BI "\-f, \-\-faketime" +Use a timestamp of 0 for inode and filesystem creation, instead of the present. Useful for testing. +.TP +.BI "\-q, \-\-squash" +Squash permissions and owners (same as -P -U). +.TP +.BI "\-U, \-\-squash\-uids" +Squash ownership of inodes added using the -d option, making them all +owned by root:root. +.TP +.BI "\-P, \-\-squash\-perms" +Squash permissions of inodes added using the -d option. Analogous to +"umask 077". +.TP +.BI "\-v, \-\-verbose" +Print resulting filesystem structure. +.TP +.BI "\-V, \-\-version" +Print genext2fs version. +.TP +.BI "\-h, \-\-help" +Display help. +.SH EXAMPLES + +.EX +.B +genext2fs -b 1440 -d src /dev/fd0 +.EE + +All files in the +.I src +directory will be written to +.B /dev/fd0 +as a new ext2 filesystem image. You can then mount the floppy as +usual. + +.EX +.B +genext2fs -b 1024 -d src -D device_table.txt flashdisk.img +.EE + +This example builds a filesystem from all the files in +.I src, +then device nodes are created based on the contents of the file +.I device_table.txt. +Entries in the device table take the form of: + +<name> <type> <mode> <uid> <gid> <major> <minor> <start> <inc> <count> + +where name is the file name and type can be one of: +.RS +.nf +f A regular file +d Directory +c Character special device file +b Block special device file +p Fifo (named pipe) +.fi +.RE +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: + +.RS +.nf +# 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 - - - - - +.fi +.RE + +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. + +.SH SEE ALSO +.BR mkfs(8), +.BR genromfs(8), +.BR mkisofs(8), +.BR mkfs.jffs2(1) +.br +.SH AUTHOR +This manual page was written by David Kimdon <dwhedon@debian.org>, +for the Debian GNU/Linux system (but may be used by others). +Examples provided by Erik Andersen <andersen@codepoet.org>. |