


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



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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.



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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 <hpa@yggdrasil.com>.  Please include the
       version number (Yggdrasil 0.3a).

AUTHOR
       Dave Hudson - <dave@humbug.demon.co.uk>; modified by Peter
       Anvin  <hpa@yggdrasil.com>.  Fixes  and additions by Roman
       Hodek	 <Roman.Hodek@informatik.uni-erlangen.de>     for
       Debian/GNU Linux.

ACKNOWLEDGEMENTS
       mkdosfs is based on code from mke2fs (written by Remy Card
       - <card@masi.ibp.fr>) which is itself based on mkfs (writ-
       ten by Linus Torvalds - <torvalds@cs.helsinki.fi>).

SEE ALSO
       dosfsck(8), mkfs(8)













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