.\" Copyright 2012 Davidlohr Bueso <dave@gnu.org>
.\" Copyright (C) 2013 Karel Zak <kzak@redhat.com>
.\" May be distributed under the GNU General Public License
-.TH FDISK 8 "September 2013" "util-linux" "System Administration"
+.TH FDISK 8 "February 2016" "util-linux" "System Administration"
.SH NAME
fdisk \- manipulate disk partition table
.SH SYNOPSIS
.B fdisk
-.RB [ options ]
+[options]
.I device
.sp
.B fdisk \-l
is able to optimize the disk layout for a 4K-sector size and use an alignment offset on
modern devices for MBR and GPT. It is always a good idea to follow \fBfdisk\fR's defaults
as the default values (e.g. first and last partition sectors) and partition
-sizes specified by the +<size>{M,G,...} notation are always aligned according
+sizes specified by the +/-<size>{M,G,...} notation are always aligned according
to the device properties.
+CHS (Cylinder-Head-Sector) addressing is deprecated and not used by default.
+Please, do not follow old articles and recommendations with "fdisk -S <n> -H
+<n>" advices for SSD or 4K-sector devices.
+
Note that
.BR partx (8)
provides a rich interface for scripts to print disk layouts,
.SH OPTIONS
.TP
-\fB\-b\fR, \fB\-\-sector-size\fR \fIsectorsize\fP
+\fB\-b\fR, \fB\-\-sector\-size\fR \fIsectorsize\fP
Specify the sector size of the disk. Valid values are 512, 1024, 2048, and 4096.
(Recent kernels know the sector size. Use this option only on old kernels or
to override the kernel's ideas.) Since util-linux-2.17, \fBfdisk\fR differentiates
between logical and physical sector size. This option changes both sector sizes to
.IB sectorsize .
.TP
-\fB\-c\fR, \fB\-\-compatibility\fR[\fI=mode\fR]
+\fB\-B\fR, \fB\-\-protect\-boot\fP
+Don't erase the begin of the first disk sector when create a new disk label. This
+feature is supported for GPT and MBR.
+.TP
+\fB\-c\fR, \fB\-\-compatibility\fR[=\fImode\fR]
Specify the compatibility mode, 'dos' or 'nondos'. The default is non-DOS
mode. For backward compatibility, it is possible to use the option without
the \fImode\fR argument -- then the default is used. Note that the optional
\fB\-h\fR, \fB\-\-help\fR
Display a help text and exit.
.TP
-\fB\-L\fR, \fB\-\-color\fR[\fI=when\fR]
-Colorize the output in interactive mode. The optional argument \fIwhen\fP can
-be \fBauto\fR, \fBnever\fR or \fBalways\fR. The default is \fBauto\fR.
+\fB\-L\fR, \fB\-\-color\fR[=\fIwhen\fR]
+Colorize the output. The optional argument \fIwhen\fP
+can be \fBauto\fR, \fBnever\fR or \fBalways\fR. If the \fIwhen\fR argument is omitted,
+it defaults to \fBauto\fR. The colors can be disabled; for the current built-in default
+see the \fB\-\-help\fR output. See also the \fBCOLORS\fR section.
.TP
\fB\-l\fR, \fB\-\-list\fR
List the partition tables for the specified devices and then exit.
Enable support only for disklabels of the specified \fItype\fP, and disable
support for all other types.
.TP
-\fB\-u\fR, \fB\-\-units\fR[\fI=unit\fR]
+\fB\-u\fR, \fB\-\-units\fR[=\fIunit\fR]
When listing partition tables, show sizes in 'sectors' or in 'cylinders'. The
default is to show sizes in sectors. For backward compatibility, it is possible
to use the option without the \fIunit\fR argument -- then the default is used.
(Not the physical number, of course, but the number used for
partition tables.) A reasonable value is 63.
+.TP
+\fB\-w\fR, \fB\-\-wipe\fR \fIwhen\fR
+Wipe filesystem, RAID and partition-table signatures from the device, in order
+to avoid possible collisions. The argument \fIwhen\fR can be \fBauto\fR,
+\fBnever\fR or \fBalways\fR. When this option is not given, the default is
+\fBauto\fR, in which case signatures are wiped only when in interactive mode.
+In all cases detected signatures are reported by warning messages
+before a new partition table is created. See also
+.BR wipefs (8)
+command.
+
+.TP
+\fB\-W\fR, \fB\-\-wipe-partition\fR \fIwhen\fR
+Wipe filesystem, RAID and partition-table signatures from a newly created
+partitions, in order to avoid possible collisions. The argument \fIwhen\fR can
+be \fBauto\fR, \fBnever\fR or \fBalways\fR. When this option is not given, the
+default is \fBauto\fR, in which case signatures are wiped only when in
+interactive mode and after confirmation by user. In all cases detected
+signatures are reported by warning messages before a new partition is
+created. See also
+.BR wipefs (8)
+command.
+
.TP
\fB\-V\fR, \fB\-\-version\fR
Display version information and exit.
.SH SIZES
The "last sector" dialog accepts partition size specified by number of sectors
-or by +<size>{K,B,M,G,...} notation.
+or by +/-<size>{K,B,M,G,...} notation.
If the size is prefixed by '+' then it is interpreted as relative to the
-partition first sector. In this case the size is expected in bytes and the
-number may be followed by the multiplicative suffixes KiB=1024, MiB=1024*1024,
-and so on for GiB, TiB, PiB, EiB, ZiB and YiB. The "iB" is optional, e.g. "K"
-has the same meaning as "KiB".
+partition first sector. If the size is prefixed by '-' then it is interpreted
+as relative to the high limit (last available sector for the partition).
+
+In the case the size is specified in bytes than the number may be followed by
+the multiplicative suffixes KiB=1024, MiB=1024*1024, and so on for GiB, TiB,
+PiB, EiB, ZiB and YiB. The "iB" is optional, e.g. "K" has the same meaning as
+"KiB".
The relative sizes are always aligned according to device I/O limits. The
-+<size>{K,B,M,G,...} notation is recommended.
++/-<size>{K,B,M,G,...} notation is recommended.
For backward compatibility fdisk also accepts the suffixes KB=1000,
MB=1000*1000, and so on for GB, TB, PB, EB, ZB and YB. These 10^N suffixes
are deprecated.
+.SH SCRIPT FILES
+.B fdisk
+allows to read (by 'I' command) sfdisk compatible script files. The script is
+applied to in-memory partition table, and then it is possible to modify the
+partition table before you write it to the device.
+.PP
+And vice-versa it is possible to write the current in-memory disk layout
+to the script file by command 'O'.
+.PP
+The script files are compatible between cfdisk, sfdisk, fdisk and another
+libfdisk applications. For more details see
+.BR sfdisk (8).
+
.SH DISK LABELS
.B GPT (GUID Partition Table)
.RS
Andries E. Brouwer, A. V. Le Blanc and others.
.SH ENVIRONMENT
+.IP FDISK_DEBUG=all
+enables fdisk debug output.
.IP LIBFDISK_DEBUG=all
enables libfdisk debug output.
.IP LIBBLKID_DEBUG=all
enables libblkid debug output.
.IP LIBSMARTCOLS_DEBUG=all
enables libsmartcols debug output.
+.IP LIBSMARTCOLS_DEBUG_PADDING=on
+use visible padding characters. Requires enabled LIBSMARTCOLS_DEBUG.
.SH "SEE ALSO"
.BR cfdisk (8),
-.BR sfdisk (8),
.BR mkfs (8),
-.BR partx (8)
+.BR partx (8),
+.BR sfdisk (8)
.SH AVAILABILITY
The fdisk command is part of the util-linux package and is available from
-ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
+https://www.kernel.org/pub/linux/utils/util-linux/.
projects / thirdparty / util-linux.git / blobdiff