dosfstools/manpages/en/mkfs.fat.8 - android_bootable_recovery - Gitiles

 .\" mkfs.fat.8 - manpage for fs.fatck
 .\"
 .\" Copyright (C) 2006-2014 Daniel Baumann <daniel@debian.org>
 .\"
 .\" This program is free software: you can redistribute it and/or modify
 .\" it under the terms of the GNU General Public License as published by
 .\" the Free Software Foundation, either version 3 of the License, or
 .\" (at your option) any later version.
 .\"
 .\" This program is distributed in the hope that it will be useful,
 .\" but WITHOUT ANY WARRANTY; without even the implied warranty of
 .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 .\" GNU General Public License for more details.
 .\"
 .\" You should have received a copy of the GNU General Public License
 .\" along with this program. If not, see <http://www.gnu.org/licenses/>.
 .\"
 .\" The complete text of the GNU General Public License
 .\" can be found in /usr/share/common-licenses/GPL-3 file.
 .\"
 .\"
 .TH MKFS.FAT 8 2015\-05\-16 3.0.28 "dosfstools"
 .SH NAME
 \fBmkfs.fat\fR \- create an MS-DOS filesystem under Linux
 .\" ----------------------------------------------------------------------------
 .SH SYNOPSIS
 \fBmkfs.fat\fR [\fIOPTIONS\fR] \fIDEVICE\fR [\fIBLOCK-COUNT\fR]
 .\" ----------------------------------------------------------------------------
 .SH DESCRIPTION
 \fBmkfs.fat\fR is used to create an MS-DOS filesystem under Linux on a device
 (usually a disk partition).
 \fIDEVICE\fR is the special file corresponding to the device (e.g. /dev/sdXX).
 \fIBLOCK-COUNT\fR is the number of blocks on the device.
 If omitted, \fBmkfs.fat\fR automatically determines the filesystem size.
 .\" ----------------------------------------------------------------------------
 .SH OPTIONS
 .IP "\fB\-a\fR" 4
 Normally, for any filesystem except very small ones, \fBmkfs.fat\fR will align
 all the data structures to cluster size, to make sure that as long as the
 partition is properly aligned, so will all the data structures in the
 filesystem.
 This option disables alignment; this may provide a handful of additional
 clusters of storage at the expense of a significant performance degradation on
 RAIDs, flash media or large-sector hard disks.
 .IP "\fB \-A\fR" 4
 Use Atari variation of the MS-DOS filesystem.
 This is default if \fBmkfs.fat\fR is run on an Atari, then this option turns off
 Atari format.
 There are some differences when using Atari format:
 If not directed otherwise by the user, \fBmkfs.fat\fR will always use 2 sectors
 per cluster, since GEMDOS doesn't like other values very much.
 It will also obey the maximum number of sectors GEMDOS can handle.
 Larger filesystems are managed by raising the logical sector 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 overridden with the \fB\-F\fR option.
 Some PC-specific boot sector fields aren't written, and a boot message (option
 \fB\-m\fR) is ignored.
 .IP "\fB\-b\fR \fISECTOR-OF-BACKUP\fR" 4
 Selects the location of the backup boot sector for FAT32.
 Default depends on number of reserved sectors, but usually is sector 6.
 The backup must be within the range of reserved sectors.
 .IP "\fB\-c" 4
 Check the device for bad blocks before creating the filesystem.
 .IP "\fB\-C\fR" 4
 Create the file given as \fIDEVICE\fR on the command line, and write the
 to-be-created filesystem to it.
 This can be used to create the new filesystem in a file instead of on a real
 device, and to avoid using \fBdd\fR in advance to create a file of appropriate
 size.
 With this option, the \fIBLOCK-COUNT\fR must be given, because otherwise the
 intended size of the filesystem wouldn't be known.
 The file created is a sparse file, which actually only contains the meta-data
 areas (boot sector, FATs, and root directory).
 The data portions won't be stored on the disk, but the file nevertheless will
 have the correct size.
 The resulting file can be copied later to a floppy disk or other device, or
 mounted through a loop device.
 .IP "\fB\-D\fR \fIDRIVE-NUMBER\fR" 4
 Specify the BIOS drive number to be stored in the FAT boot sector.
 This value is usually 0x80 for hard disks and 0x00 for floppy devices or
 partitions to be used for floppy emulation.
 .IP "\fB\-f\fR \fINUMBER-OF-FATS\fR" 4
 Specify the number of file allocation tables in the filesystem.
 The default is 2.
 .IP "\fB\-F\fR \fIFAT-SIZE\fR" 4
 Specifies the type of file allocation tables used (12, 16 or 32 bit).
 If nothing is specified, \fBmkfs.fat\fR will automatically select between 12, 16
 and 32 bit, whatever fits better for the filesystem size.
 .IP "\fB\-h\fR \fINUMBER-OF-HIDDEN-SECTORS\fR" 4
 Select the number of hidden sectors in the volume.
 Apparently some digital cameras get indigestion if you feed them a CF card
 without such hidden sectors, this option allows you to satisfy them.
 .IP "\fB\-i\fR \fIVOLUME-ID\fR" 4
 Sets the volume ID of the newly created filesystem; \fIVOLUME-ID\fR is a 32-bit
 hexadecimal number (for example, 2e24ec82).
 The default is a number which depends on the filesystem creation time.
 .IP "\fB\-I\fR" 4
 It is typical for fixed disk devices to be partitioned so, by default, you are
 not permitted to create a filesystem across the entire device.
 \fBmkfs.fat\fR will complain and tell you that it refuses to work.
 This is different when using MO disks.
 One doesn't always need partitions on MO disks.
 The filesystem can go directly to the whole disk.
 Under other OSes this is known as the 'superfloppy' format.
 This switch will force \fBmkfs.fat\fR to work properly.
 .IP "\fB\-l\fR \fIFILENAME\fR" 4
 Read the bad blocks list from \fIFILENAME\fR.
 .IP "\fB\-m\fR \fIMESSAGE-FILE\fR" 4
 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 combinations, and tabs have been expanded.
 If the filename is a hyphen (-), the text is taken from standard input.
 .IP "\fB\-M\fR \fIFAT-MEDIA-TYPE\fR" 4
 Specify the media type to be stored in the FAT boot sector.
 This value is usually 0xF8 for hard disks and is 0xF0 or a value from 0xF9 to
 0xFF for floppies or partitions to be used for floppy emulation.
 .IP "\fB\-n\fR \fIVOLUME-NAME\fR" 4
 Sets the volume name (label) of the filesystem.
 The volume name can be up to 11 characters long.
 The default is no label.
 .IP "\fB\-r\fR \fIROOT-DIR-ENTRIES\fR" 4
 Select the number of entries available in the root directory.
 The default is 112 or 224 for floppies and 512 for hard disks.
 .IP "\fB\-R\fR \fINUMBER-OF-RESERVED-SECTORS\fR" 4
 Select the number of reserved sectors.
 With FAT32 format at least 2 reserved sectors are needed, the default is 32.
 Otherwise the default is 1 (only the boot sector).
 .IP "\fB\-s\fR \fISECTORS-PER-CLUSTER\fR" 4
 Specify the number of disk sectors per cluster.
 Must be a power of 2, i.e. 1, 2, 4, 8, ... 128.
 .IP "\fB\-S\fR \fILOGICAL-SECTOR-SIZE\fR" 4
 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.
 .IP "\fB\-v\fR" 4
 Verbose execution.
 .IP "\fB\-\-invariant\fR" 4
 Use constants for normally randomly generated or time based data such as
 volume ID and creation time.
 Multiple runs of \fBmkfs.fat\fR on the same device create identical results
 with this option.
 Its main purpose is testing \fBmkfs.fat\fR.
 .IP "\fB\-\-help\fR" 4
 Display option summary and exit.
 .\" ----------------------------------------------------------------------------
 .SH BUGS
 \fBmkfs.fat\fR can not create boot-able filesystems.
 This isn't as easy as you might think at first glance for various reasons and
 has been discussed a lot already.
 \fBmkfs.fat\fR simply will not support it ;)
 .\" ----------------------------------------------------------------------------
 .SH SEE ALSO
 \fBfatlabel\fR(8)
 .br
 \fBfsck.fat\fR(8)
 .\" ----------------------------------------------------------------------------
 .SH HOMEPAGE
 The home for the \fBdosfstools\fR project is its
 .UR https://github.com/dosfstools/dosfstools
 GitHub project page
 .UE .
 .\" ----------------------------------------------------------------------------
 .SH AUTHORS
 \fBdosfstools\fR were written by
 .MT werner.almesberger@\:lrc.di.epfl.ch
 Werner Almesberger
 .ME ,
 .MT Roman.Hodek@\:informatik.\:uni-erlangen.de
 Roman Hodek
 .ME ,
 and others.
 The current maintainer is
 .MT aeb@\:debian.org
 Andreas Bombe
 .ME .
	.\" mkfs.fat.8 - manpage for fs.fatck
	.\"
	.\" Copyright (C) 2006-2014 Daniel Baumann <daniel@debian.org>
	.\"
	.\" This program is free software: you can redistribute it and/or modify
	.\" it under the terms of the GNU General Public License as published by
	.\" the Free Software Foundation, either version 3 of the License, or
	.\" (at your option) any later version.
	.\"
	.\" This program is distributed in the hope that it will be useful,
	.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
	.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	.\" GNU General Public License for more details.
	.\"
	.\" You should have received a copy of the GNU General Public License
	.\" along with this program. If not, see <http://www.gnu.org/licenses/>.
	.\"
	.\" The complete text of the GNU General Public License
	.\" can be found in /usr/share/common-licenses/GPL-3 file.
	.\"
	.\"
	.TH MKFS.FAT 8 2015\-05\-16 3.0.28 "dosfstools"
	.SH NAME
	\fBmkfs.fat\fR \- create an MS-DOS filesystem under Linux
	.\" ----------------------------------------------------------------------------
	.SH SYNOPSIS
	\fBmkfs.fat\fR [\fIOPTIONS\fR] \fIDEVICE\fR [\fIBLOCK-COUNT\fR]
	.\" ----------------------------------------------------------------------------
	.SH DESCRIPTION
	\fBmkfs.fat\fR is used to create an MS-DOS filesystem under Linux on a device
	(usually a disk partition).
	\fIDEVICE\fR is the special file corresponding to the device (e.g. /dev/sdXX).
	\fIBLOCK-COUNT\fR is the number of blocks on the device.
	If omitted, \fBmkfs.fat\fR automatically determines the filesystem size.
	.\" ----------------------------------------------------------------------------
	.SH OPTIONS
	.IP "\fB\-a\fR" 4
	Normally, for any filesystem except very small ones, \fBmkfs.fat\fR will align
	all the data structures to cluster size, to make sure that as long as the
	partition is properly aligned, so will all the data structures in the
	filesystem.
	This option disables alignment; this may provide a handful of additional
	clusters of storage at the expense of a significant performance degradation on
	RAIDs, flash media or large-sector hard disks.
	.IP "\fB \-A\fR" 4
	Use Atari variation of the MS-DOS filesystem.
	This is default if \fBmkfs.fat\fR is run on an Atari, then this option turns off
	Atari format.
	There are some differences when using Atari format:
	If not directed otherwise by the user, \fBmkfs.fat\fR will always use 2 sectors
	per cluster, since GEMDOS doesn't like other values very much.
	It will also obey the maximum number of sectors GEMDOS can handle.
	Larger filesystems are managed by raising the logical sector 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 overridden with the \fB\-F\fR option.
	Some PC-specific boot sector fields aren't written, and a boot message (option
	\fB\-m\fR) is ignored.
	.IP "\fB\-b\fR \fISECTOR-OF-BACKUP\fR" 4
	Selects the location of the backup boot sector for FAT32.
	Default depends on number of reserved sectors, but usually is sector 6.
	The backup must be within the range of reserved sectors.
	.IP "\fB\-c" 4
	Check the device for bad blocks before creating the filesystem.
	.IP "\fB\-C\fR" 4
	Create the file given as \fIDEVICE\fR on the command line, and write the
	to-be-created filesystem to it.
	This can be used to create the new filesystem in a file instead of on a real
	device, and to avoid using \fBdd\fR in advance to create a file of appropriate
	size.
	With this option, the \fIBLOCK-COUNT\fR must be given, because otherwise the
	intended size of the filesystem wouldn't be known.
	The file created is a sparse file, which actually only contains the meta-data
	areas (boot sector, FATs, and root directory).
	The data portions won't be stored on the disk, but the file nevertheless will
	have the correct size.
	The resulting file can be copied later to a floppy disk or other device, or
	mounted through a loop device.
	.IP "\fB\-D\fR \fIDRIVE-NUMBER\fR" 4
	Specify the BIOS drive number to be stored in the FAT boot sector.
	This value is usually 0x80 for hard disks and 0x00 for floppy devices or
	partitions to be used for floppy emulation.
	.IP "\fB\-f\fR \fINUMBER-OF-FATS\fR" 4
	Specify the number of file allocation tables in the filesystem.
	The default is 2.
	.IP "\fB\-F\fR \fIFAT-SIZE\fR" 4
	Specifies the type of file allocation tables used (12, 16 or 32 bit).
	If nothing is specified, \fBmkfs.fat\fR will automatically select between 12, 16
	and 32 bit, whatever fits better for the filesystem size.
	.IP "\fB\-h\fR \fINUMBER-OF-HIDDEN-SECTORS\fR" 4
	Select the number of hidden sectors in the volume.
	Apparently some digital cameras get indigestion if you feed them a CF card
	without such hidden sectors, this option allows you to satisfy them.
	.IP "\fB\-i\fR \fIVOLUME-ID\fR" 4
	Sets the volume ID of the newly created filesystem; \fIVOLUME-ID\fR is a 32-bit
	hexadecimal number (for example, 2e24ec82).
	The default is a number which depends on the filesystem creation time.
	.IP "\fB\-I\fR" 4
	It is typical for fixed disk devices to be partitioned so, by default, you are
	not permitted to create a filesystem across the entire device.
	\fBmkfs.fat\fR will complain and tell you that it refuses to work.
	This is different when using MO disks.
	One doesn't always need partitions on MO disks.
	The filesystem can go directly to the whole disk.
	Under other OSes this is known as the 'superfloppy' format.
	This switch will force \fBmkfs.fat\fR to work properly.
	.IP "\fB\-l\fR \fIFILENAME\fR" 4
	Read the bad blocks list from \fIFILENAME\fR.
	.IP "\fB\-m\fR \fIMESSAGE-FILE\fR" 4
	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 combinations, and tabs have been expanded.
	If the filename is a hyphen (-), the text is taken from standard input.
	.IP "\fB\-M\fR \fIFAT-MEDIA-TYPE\fR" 4
	Specify the media type to be stored in the FAT boot sector.
	This value is usually 0xF8 for hard disks and is 0xF0 or a value from 0xF9 to
	0xFF for floppies or partitions to be used for floppy emulation.
	.IP "\fB\-n\fR \fIVOLUME-NAME\fR" 4
	Sets the volume name (label) of the filesystem.
	The volume name can be up to 11 characters long.
	The default is no label.
	.IP "\fB\-r\fR \fIROOT-DIR-ENTRIES\fR" 4
	Select the number of entries available in the root directory.
	The default is 112 or 224 for floppies and 512 for hard disks.
	.IP "\fB\-R\fR \fINUMBER-OF-RESERVED-SECTORS\fR" 4
	Select the number of reserved sectors.
	With FAT32 format at least 2 reserved sectors are needed, the default is 32.
	Otherwise the default is 1 (only the boot sector).
	.IP "\fB\-s\fR \fISECTORS-PER-CLUSTER\fR" 4
	Specify the number of disk sectors per cluster.
	Must be a power of 2, i.e. 1, 2, 4, 8, ... 128.
	.IP "\fB\-S\fR \fILOGICAL-SECTOR-SIZE\fR" 4
	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.
	.IP "\fB\-v\fR" 4
	Verbose execution.
	.IP "\fB\-\-invariant\fR" 4
	Use constants for normally randomly generated or time based data such as
	volume ID and creation time.
	Multiple runs of \fBmkfs.fat\fR on the same device create identical results
	with this option.
	Its main purpose is testing \fBmkfs.fat\fR.
	.IP "\fB\-\-help\fR" 4
	Display option summary and exit.
	.\" ----------------------------------------------------------------------------
	.SH BUGS
	\fBmkfs.fat\fR can not create boot-able filesystems.
	This isn't as easy as you might think at first glance for various reasons and
	has been discussed a lot already.
	\fBmkfs.fat\fR simply will not support it ;)
	.\" ----------------------------------------------------------------------------
	.SH SEE ALSO
	\fBfatlabel\fR(8)
	.br
	\fBfsck.fat\fR(8)
	.\" ----------------------------------------------------------------------------
	.SH HOMEPAGE
	The home for the \fBdosfstools\fR project is its
	.UR https://github.com/dosfstools/dosfstools
	GitHub project page
	.UE .
	.\" ----------------------------------------------------------------------------
	.SH AUTHORS
	\fBdosfstools\fR were written by
	.MT werner.almesberger@\:lrc.di.epfl.ch
	Werner Almesberger
	.ME ,
	.MT Roman.Hodek@\:informatik.\:uni-erlangen.de
	Roman Hodek
	.ME ,
	and others.
	The current maintainer is
	.MT aeb@\:debian.org
	Andreas Bombe
	.ME .