MKDOSFS(8) MKDOSFS(8) NAME mkdosfs - create an MS-DOS file system under Linux SYNOPSIS mkdosfs [ -A ] [ -b sector-of-backup ] [ -c ] [ -l file- name ] [ -C ] [ -f number-of-FATs ] [ -F FAT-size ] [ -i volume-id ] [ -I ] [ -m message-file ] [ -n volume-name ] [ -r root-dir-entries ] [ -R number-of-reserved-sectors ] [ -s sectors-per-cluster ] [ -S logical-sector-size ] [ -v ] device [ block-count ] DESCRIPTION mkdosfs is used to create an MS-DOS file system under Linux on a device (usually a disk partition). device is the special file corresponding to the device (e.g /dev/hdXX). block-count is the number of blocks on the device. If omitted, mkdosfs automatically determiness the file system size. OPTIONS -A Use Atari variation of the MS-DOS filesystem. This is default if mkdosfs is run on an Atari, then this option turns off Atari format. There are some dif- ferences when using Atari format: If not directed otherwise by the user, mkdosfs will always use 2 sectors per cluster, since GEMDOS doesn't like other values very much. It will also obey the max- imum number of sectors GEMDOS can handle. Larger filesystems are managed by raising the logical sec- tor size. Under Atari format, an Atari-compatible serial number for the filesystem is generated, and a 12 bit FAT is used only for filesystems that have one of the usual floppy sizes (720k, 1.2M, 1.44M, 2.88M), a 16 bit FAT otherwise. This can be over- ridden with the -F option. Some PC-specific boot sector fields aren't written, and a boot message (option -m) is ignored. -b sector-of-backup Selects the location of the backup boot sector for FAT32. Default depends on number of reserved sec- tors, but usually is sector 6. The backup must be within the range of reserved sectors. -c Check the device for bad blocks before creating the file system. -C Create the file given as device on the command line, and write the to-be-created file system to it. This can be used to create the new file system in a file instead of on a real device, and to avoid using dd in advance to create a file of appropriate size. With this option, the block-count must be given, because otherwise the intended size of the Version 2.x 5 May 1995 1 MKDOSFS(8) MKDOSFS(8) file system wouldn't be known. The file created is a sparse file, which actually only contains the meta-data areas (boot sector, FATs, and root direc- tory). The data portions won't be stored on the disk, but the file nevertheless will have the cor- rect size. The resulting file can be copied later to a floppy disk or other device, or mounted through a loop device. -f number-of-FATs Specify the number of file allocation tables in the file system. The default is 2. Currently the Linux MS-DOS file system does not support more than 2 FATs. -F FAT-size Specifies the type of file allocation tables used (12, 16 or 32 bit). If nothing is specified, mkdosfs will automatically select between 12 and 16 bit, whatever fits better for the filesystem size. 32 bit FAT (FAT32 format) must (still) be selected explicitly if you want it. -i volume-id Sets the volume ID of the newly created filesystem; volume-id is a 32-bit hexadecimal number (for exam- ple, 2e24ec82). The default is a number which depends on the filesystem creation time. -I Normally you are not allowed to use any 'full' fixed disk devices. mkdosfs will complain and tell you that it refuses to work. This is different when usind MO disks. One doesn't always need par- titions on MO disks. The filesytem can go directly to the whole disk. Under other OSes this is known as the 'superfloppy' format. This switch will force mkdosfs to work properly. -l filename Read the bad blocks list from filename. -m message-file Sets the message the user receives on attempts to boot this filesystem without having properly installed an operating system. The message file must not exceed 418 bytes once line feeds have been converted to carriage return-line feed combina- tions, and tabs have been expanded. If the file- name is a hyphen (-), the text is taken from stan- dard input. -n volume-name Sets the volume name (label) of the filesystem. Version 2.x 5 May 1995 2 MKDOSFS(8) MKDOSFS(8) The volume name can be up to 11 characters long. The default is no label. -r root-dir-entries Select the number of entries available in the root directory. The default is 112 or 224 for floppies and 512 for hard disks. -R number-of-reserved-sectors Select the number of reserved sectos. With FAT32 format at least 2 reserved sectors are needed, the default is 32. Otherwise the default is 1 (only the boot sector). -s sectors-per-cluster Specify the number of disk sectors per cluster. Must be a power of 2, i.e. 1, 2, 4, 8, ... 128. -S logical-sector-size Specify the number of bytes per logical sector. Must be a power of 2 and greater than or equal to 512, i.e. 512, 1024, 2048, 4096, 8192, 16384, or 32768. -v Verbose execution. BUGS None are know at the moment. If you find any, please report it them to . Please include the version number (Yggdrasil 0.3a). AUTHOR Dave Hudson - ; modified by Peter Anvin . Fixes and additions by Roman Hodek for Debian/GNU Linux. ACKNOWLEDGEMENTS mkdosfs is based on code from mke2fs (written by Remy Card - ) which is itself based on mkfs (writ- ten by Linus Torvalds - ). SEE ALSO dosfsck(8), mkfs(8) Version 2.x 5 May 1995 3