GDISK(8)		       GPT fdisk Manual			      GDISK(8)



NAME
       gdisk - Interactive GUID partition table (GPT) manipulator

SYNOPSIS
       gdisk [ -l ] device


DESCRIPTION
       GPT  fdisk  (aka gdisk) is a text-mode menu-driven program for creation
       and manipulation of partition tables. It will automatically convert  an
       old-style  Master  Boot	Record	(MBR) partition table or BSD disklabel
       stored without an MBR carrier partition to the  newer  Globally	Unique
       Identifier  (GUID)  Partition  Table  (GPT) format, or will load a GUID
       partition table. When used with the -l command-line option, the program
       displays the current partition table and then exits.

       GPT fdisk operates mainly on the GPT headers and partition tables; how-
       ever, it can and will generate a fresh protective MBR,  when  required.
       (Any  boot loader code in the protective MBR will not be disturbed.) If
       you've created an unusual protective MBR, such as a hybrid MBR  created
       by  gptsync or gdisk's own hybrid MBR creation feature, this should not
       be disturbed by most ordinary  actions.	Some  advanced	data  recovery
       options require you to understand the distinctions between the main and
       backup data, as well as between	the  GPT  headers  and	the  partition
       tables.	For information on MBR vs. GPT, as well as GPT terminology and
       structure, see the extended  gdisk  documentation  at  http://www.rods-
       books.com/gdisk/ or consult Wikipedia.

       The  gdisk  program employs a user interface similar to that of Linux's
       fdisk, but gdisk modifies GPT partitions. It also has the capability of
       transforming MBR partitions or BSD disklabels into GPT partitions. Like
       the original fdisk program, gdisk does not modify disk structures until
       you  explicitly	write  them to disk, so if you make a mistake, you can
       exit from the program with the 'q'  option  to  leave  your  partitions
       unmodified.

       Ordinarily,  gdisk  operates  on disk device files, such as /dev/sda or
       /dev/hda under Linux,  /dev/disk0  under	 Mac  OS  X,  or  /dev/ad0  or
       /dev/da0	 under	FreeBSD.  The  program	can also operate on disk image
       files, which can be either copies of whole disks	 (made	with  dd,  for
       instance)  or raw disk images used by emulators such as QEMU or VMWare.
       Note that only raw disk images are supported; gdisk cannot work on com-
       pressed or other advanced disk image formats.

       The  MBR partitioning system uses a combination of cylinder/head/sector
       (CHS) addressing and logical block  addressing  (LBA).  The  former  is
       klunky  and limiting. GPT drops CHS addressing and uses 64-bit LBA mode
       exclusively. Thus, GPT data structures, and  therefore  gdisk,  do  not
       need  to	 deal  with  CHS  geometries and all the problems they create.
       Users of fdisk will note that gdisk lacks the options  and  limitations
       associated with CHS geometries.

       For best results, you should use an OS-specific partition table program
       whenever possible. For example, you should make	Mac  OS	 X  partitions
       with  the  Mac  OS X Disk Utility program and Linux partitions with the
       Linux gdisk or GNU Parted program.

       Upon start, gdisk attempts to identify the partition type in use on the
       disk.  If  it finds valid GPT data, gdisk will use it. If gdisk finds a
       valid MBR or BSD disklabel but no GPT data, it will attempt to  convert
       the  MBR or disklabel into GPT form. (BSD disklabels are likely to have
       unusable first and/or final partitions because they  overlap  with  the
       GPT  data structures, though.) GPT fdisk can identify, but not use data
       in, Apple Partition Map (APM) disks, which are used on 680x0- and  Pow-
       erPC-based  Macintoshes.	 Upon  exiting	with  the  'w'	option,	 gdisk
       replaces the MBR or disklabel with a GPT. This  action  is  potentially
       dangerous!  Your system may become unbootable, and partition type codes
       may become corrupted if the disk uses  unrecognized  type  codes.  Boot
       problems	 are  particularly  likely  if	you're	multi-booting with any
       GPT-unaware OS. If you mistakenly launch gdisk on an MBR disk, you  can
       safely  exit  the  program  without making any changes by using the 'q'
       option.

       The MBR-to-GPT conversion will leave at least one gap in the  partition
       numbering  if  the original MBR used logical partitions. These gaps are
       harmless, but you can eliminate them by using the 's'  option,  if  you
       like.  (Doing this may require you to update your /etc/fstab file.)

       When creating a fresh partition table, certain considerations may be in
       order:


       *      For data (non-boot) disks, and for boot disks used on BIOS-based
	      computers	 with  GRUB as the boot loader, partitions may be cre-
	      ated in whatever order and in whatever sizes are desired.


       *      Boot disks for EFI-based systems require an EFI System Partition
	      (gdisk  internal	code  0xEF00) formatted as FAT-32.  The recom-
	      mended size of this  partition  is  between  100	and  300  MiB.
	      Boot-related  files are stored here. (Note that GNU Parted iden-
	      tifies such partitions as having the "boot flag" set.)


       *      Some boot loaders for BIOS-based systems make use of a BIOS Boot
	      Partition	 (gdisk	 internal code 0xEF02), in which the secondary
	      boot loader  is  stored,	possibly  without  the	benefit	 of  a
	      filesystem.  (GRUB2  may	optionally use such a partition.) This
	      partition can typically be quite small (roughly 32 to 200	 KiB),
	      but  you	should	consult	 your  boot  loader  documentation for
	      details.


       *      If Windows is to boot from a GPT disk, a partition of  type  Mi-
	      crosoft  Reserved	 (gdisk	 internal code 0x0C01) is recommended.
	      This partition should be about 128 MiB in	 size.	It  ordinarily
	      follows  the  EFI	 System Partition and immediately precedes the
	      Windows data partitions. (Note that old versions of  GNU	Parted
	      create all FAT partitions as this type, which actually makes the
	      partition unusable for normal file storage in both  Windows  and
	      Mac OS X.)


       *      Some  OSes' GPT utilities create some blank space (typically 128
	      MiB) after each partition. The intent is to enable  future  disk
	      utilities	 to use this space. Such free space is not required of
	      GPT disks, but creating it may help in future disk  maintenance.
	      You  can	use  GPT fdisk's relative partition positioning option
	      (specifying the starting sector as  '+128M',  for	 instance)  to
	      simplify creating such gaps.


OPTIONS
       -l     List  the	 partition  table  for	the  specified device and then
	      exits.

       Most interactions with  gdisk  occur  with  its	interactive  text-mode
       menus.  Three menus exist: the main menu, the recovery & transformation
       menu, and the experts' menu. The main menu provides the functions  that
       are  most  likely  to be useful for typical partitioning tasks, such as
       creating and deleting partitions, changing partition type codes, and so
       on. Specific functions are:


       b      Save  partition data to a backup file. You can back up your cur-
	      rent in-memory partition table to a disk file using this option.
	      The resulting file is a binary file consisting of the protective
	      MBR, the main GPT header, the backup GPT header, and one copy of
	      the  partition  table, in that order. Note that the backup is of
	      the current in-memory data structures, so if you launch the pro-
	      gram,  make  changes,  and then use this option, the backup will
	      reflect your changes. Note also that the restore	option	is  on
	      the  recovery & transformation menu; the backup option is on the
	      main menu to encourage its use.



       c      Change the GPT name of a partition. This name is	encoded	 as  a
	      UTF-16  string,  but proper entry and display of anything beyond
	      basic ASCII values requires suitable locale  and	font  support.
	      For  the most part, Linux ignores the partition name, but it may
	      be important in some OSes. GPT fdisk sets a default  name	 based
	      on  the partition type code. Note that the GPT partition name is
	      different from the filesystem name,  which  is  encoded  in  the
	      filesystem's data structures.


       d      Delete  a partition. This action deletes the entry from the par-
	      tition table but does not disturb the data  within  the  sectors
	      originally  allocated  to the partition on the disk. If a corre-
	      sponding hybrid MBR partition exists, gdisk deletes it, as well,
	      and expands any adjacent 0xEE (EFI GPT) MBR protective partition
	      to fill the new free space.


       i      Show detailed partition  information.  The  summary  information
	      produced by the 'p' command necessarily omits many details, such
	      as the partition's unique GUID and the  translation  of  gdisk's
	      internal	partition  type	 code  to  a  plain type name. The 'i'
	      option displays this information for a single partition.


       l      Display a summary of partition types. GPT uses a GUID  to	 iden-
	      tify  partition types for particular OSes and purposes. For ease
	      of data entry, gdisk compresses these into two-byte  (four-digit
	      hexadecimal)  values  that  are  related to their equivalent MBR
	      codes. Specifically, the MBR code is multiplied  by  hexadecimal
	      0x0100.  For  instance,  the code for Linux swap space in MBR is
	      0x82, and it's 0x8200 in gdisk. A one-to-one  correspondence  is
	      impossible, though. Most notably, the codes for all varieties of
	      FAT and NTFS partition correspond to a single GPT code  (entered
	      as 0x0700 in sgdisk). Some OSes use a single MBR code but employ
	      many more codes in GPT.  For  these,  gdisk  adds	 code  numbers
	      sequentially, such as 0xa500 for a FreeBSD disklabel, 0xa501 for
	      FreeBSD boot, 0xa502 for FreeBSD swap,  and  so  on.  Note  that
	      these two-byte codes are unique to gdisk.


       n      Create  a	 new  partition.  This	command	 is modelled after the
	      equivalent fdisk option, although some  differences  exist.  You
	      enter a partition number, starting sector, and an ending sector.
	      Both start and end sectors can be specified in absolute terms as
	      sector  numbers  or  as  positions  measured  in	kibibytes (K),
	      mebibytes (M), gibibytes (G), tebibytes (T), or  pebibytes  (P);
	      for  instance,  40M specifies a position 40MiB from the start of
	      the disk. You can specify locations relative to the start or end
	      of  the specified default range by preceding the number by a '+'
	      or '-' symbol, as in +2G to  specify  a  point  2GiB  after  the
	      default  start sector, or -200M to specify a point 200MiB before
	      the last available sector. Pressing the Enter key with no	 input
	      specifies	 the  default value, which is the start of the largest
	      available block for the start sector and the  end	 of  the  same
	      block for the end sector.


       o      Clear out all partition data. This includes GPT header data, all
	      partition definitions, and the protective MBR. The sector align-
	      ment is reset to the default (2048 sectors, or 1MB).


       p      Display  basic  partition	 summary data. This includes partition
	      numbers, starting and ending sector  numbers,  partition	sizes,
	      gdisk's  partition  types	 codes, and partition names. For addi-
	      tional information, use the 'i' command.


       q      Quit from the program without saving  your  changes.   Use  this
	      option  if  you just wanted to view information or if you make a
	      mistake and want to back out of all your changes.


       r      Enter the recovery & transformation  menu.  This	menu  includes
	      emergency	 recovery options (to fix damaged GPT data structures)
	      and options to transform to or from other partitioning  systems,
	      including creating hybrid MBRs.


       s      Sort partition entries. GPT partition numbers need not match the
	      order of partitions on the disk. If you want them to match,  you
	      can use this option.  Note that some partitioning utilities sort
	      partitions whenever they make  changes.  Such  changes  will  be
	      reflected	 in  your  device  filenames,  so you may need to edit
	      /etc/fstab if you use this option.


       t      Change a single partition's type code. You enter the  type  code
	      using  a	two-byte hexadecimal number, as described earlier. You
	      may also enter a GUID  directly,	if  you	 have  one  and	 gdisk
	      doesn't know it.


       v      Verify  disk. This option checks for a variety of problems, such
	      as incorrect CRCs and mismatched	main  and  backup  data.  This
	      option does not automatically correct most problems, though; for
	      that, you must use options  on  the  recovery  &	transformation
	      menu.  If no problems are found, this command displays a summary
	      of unallocated disk space.


       w      Write data. Use this command to save your changes.


       x      Enter the experts' menu. Using this option  provides  access  to
	      features you can use to get into even more trouble than the main
	      menu allows.

       ?      Print the menu. Type this command	 (or  any  other  unrecognized
	      command) to see a summary of available options.


       The second gdisk menu is the recovery & transformation menu, which pro-
       vides access to data recovery  options  and  features  related  to  the
       transformation  of  partitions between partitioning schemes (converting
       BSD disklabels  into  GPT  partitions  or  creating  hybrid  MBRs,  for
       instance).   A  few options on this menu duplicate functionality on the
       main menu, for the sake of convenience. The options on this menu are:


       b      Rebuild GPT header from backup.  You  can	 use  the  backup  GPT
	      header  to  rebuild  the	main GPT header with this option. It's
	      likely to be useful if your  main	 GPT  header  was  damaged  or
	      destroyed (say, by sloppy use of dd).


       c      Load  backup  partition  table.  Ordinarily, gdisk uses only the
	      main partition table (although the backup's integrity is checked
	      when  you	 launch	 the program). If the main partition table has
	      been damaged, you can use this option to load  the  backup  from
	      disk  and	 use  it instead. Note that this will almost certainly
	      produce no or strange partition entries if you've just converted
	      an  MBR disk to GPT format, since there will be no backup parti-
	      tion table on disk.


       d      Use main GPT header and  rebuild	the  backup.  This  option  is
	      likely to be useful if the backup GPT header has been damaged or
	      destroyed.


       e      Load main partition table. This option reloads the  main	parti-
	      tion  table  from	 disk. It's only likely to be useful if you've
	      tried to use the backup partition table (via 'c')	 but  it's  in
	      worse shape then the main partition table.


       f      Load  MBR	 and  build fresh GPT from it. Use this option if your
	      GPT is corrupt or conflicts with the MBR and you want to use the
	      MBR as the basis for a new set of GPT partitions.


       g      Convert GPT into MBR and exit. This option converts as many par-
	      titions as possible into MBR form, destroys the GPT data	struc-
	      tures,  saves the new MBR, and exits.  Use this option if you've
	      tried GPT and find that MBR works better	for  you.   Note  that
	      this  function  generates	 up  to four primary MBR partitions or
	      three primary partitions and as many logical partitions  as  can
	      be generated. Each logical partition requires at least one unal-
	      located block immediately before its first block. Therefore,  it
	      may be possible to convert a maximum of four partitions on disks
	      with tightly-packed  partitions;	however,  if  free  space  was
	      inserted	between	 partitions when they were created, and if the
	      disk is under 2 TiB in size, it should be	 possible  to  convert
	      all the partitions to MBR form.  See also the 'h' option.


       h      Create  a	 hybrid	 MBR.  This is an ugly workaround that enables
	      GPT-unaware OSes, or those that can't boot from a GPT  disk,  to
	      access up to three of the partitions on the disk by creating MBR
	      entries for them. Note that these hybrid MBR entries can	easily
	      go   out	of  sync  with	the  GPT  entries,  particularly  when
	      hybrid-unaware GPT utilities are used to edit the	 disk.	 Thus,
	      you  may need to re-create the hybrid MBR if you use such tools.
	      Unlike the 'g' option, this option does not  support  converting
	      any partitions into MBR logical partitions.


       i      Show detailed partition information. This option is identical to
	      the 'i' option on the main menu.


       l      Load partition data from a  backup  file.	 This  option  is  the
	      reverse  of the 'b' option on the main menu. Note that restoring
	      partition data from anything but the original disk is not recom-
	      mended.


       m      Return  to  the  main  menu.  This  option  enables you to enter
	      main-menu commands.


       o      Print protective MBR data. You can see a summary of the  protec-
	      tive  MBR's  partitions with this option. This may enable you to
	      spot glaring problems or	help  identify	the  partitions	 in  a
	      hybrid MBR.


       p      Print  the  partition table. This option is identical to the 'p'
	      option in the main menu.


       q      Quit without saving changes. This option is identical to the 'q'
	      option in the main menu.


       t      Transform	 BSD partitions into GPT partitions. This option works
	      on BSD disklabels held within GPT (or converted MBR) partitions.
	      Converted	 partitions'  type  codes  are	likely	to need manual
	      adjustment. gdisk will attempt to convert BSD disklabels	stored
	      on the main disk when launched, but this conversion is likely to
	      produce first and/or last partitions that are unusable. The many
	      BSD variants means that the probability of gdisk being unable to
	      convert a BSD disklabel is high compared to  the	likelihood  of
	      problems with an MBR conversion.


       v      Verify  disk.  This option is identical to the 'v' option in the
	      main menu.


       w      Write table to disk and exit. This option is  identical  to  the
	      'w' option in the main menu.


       x      Enter  the  experts'  menu.  This option is identical to the 'x'
	      option in the main menu.


       ?      Print the menu. This option (or any unrecognized entry) displays
	      a summary of the menu options.


       The  third gdisk menu is the experts' menu. This menu provides advanced
       options that aren't  closely  related  to  recovery  or	transformation
       between partitioning systems. Its options are:


       a      Set  attributes. GPT provides a 64-bit attributes field that can
	      be used to set features for each partition. gdisk supports  four
	      attributes:  system  partition,  read-only,  hidden,  and do not
	      automount. You can  set  other  attributes,  but	their  numbers
	      aren't  translated  into anything useful. In practice, most OSes
	      seem to ignore these attributes.


       c      Change partition GUID. You can enter a custom unique GUID for  a
	      partition	 using this option. (Note this refers to the GUID that
	      uniquely identifies a partition, not to its type code, which you
	      can  change  with	 the  't' main-menu option.) Ordinarily, gdisk
	      assigns this number randomly; however, you might want to	adjust
	      the number manually if you've wound up with the same GUID on two
	      partitions because of buggy GUID assignments (hopefully  not  in
	      gdisk) or sheer incredible coincidence.


       d      Display  the  sector alignment value. See the description of the
	      'l' option for more details.


       e      Move backup GPT data structures to the end of the disk. Use this
	      command  if  you've added disks to a RAID array, thus creating a
	      virtual disk with space that follows the backup GPT data	struc-
	      tures.  This command moves the backup GPT data structures to the
	      end of the disk, where they belong.


       f      Randomize the disk's GUID and all partitions' unique GUIDs  (but
	      not  their partition type code GUIDs). This function may be used
	      after cloning a disk with another utility in order to render all
	      GUIDs once again unique.


       g      Change  disk GUID. Each disk has a unique GUID code, which gdisk
	      assigns randomly upon creation of the GPT data  structures.  You
	      can generate a fresh random GUID or enter one manually with this
	      option.


       h      Recompute CHS values in protective or hybrid  MBR.  This	option
	      can  sometimes  help if a disk utility, OS, or BIOS doesn't like
	      the CHS values used by  the  partitions  in  the	protective  or
	      hybrid  MBR. In particular, the GPT specification requires a CHS
	      value of 0xFFFFFF for over-8GiB partitions, but  this  value  is
	      technically  illegal by the usual standards. Some BIOSes hang if
	      they encounter this value. This option  will  recompute  a  more
	      normal  CHS value -- 0xFEFFFF for over-8GiB partitions, enabling
	      these BIOSes to boot.


       i      Show detailed partition information. This option is identical to
	      the 'i' option on the main menu.


       l      Change  the sector alignment value. Disks with more logical sec-
	      tors per	physical  sectors  (such  as  modern  Advanced	Format
	      drives),	some  RAID  configurations,  and many SSD devices, can
	      suffer performance problems if partitions are not aligned	 prop-
	      erly for their internal data structures. On new disks, GPT fdisk
	      attempts to align partitions on 2048-sector (1MiB) boundaries by
	      default,	which  optimizes  performance  for  all	 of these disk
	      types. On pre-partitioned disks, GPT fdisk attempts to  identify
	      the  alignment  value  used  on that disk, but will set 8-sector
	      alignment on disks larger than 300 GB even if  lesser  alignment
	      values  are detected. In either case, it can be changed by using
	      this option.


       m      Return to the main  menu.	 This  option  enables	you  to	 enter
	      main-menu commands.


       n      Create a new protective MBR. Use this option if the current pro-
	      tective MBR is damaged in a way that gdisk doesn't automatically
	      detect  and correct, or if you want to convert a hybrid MBR into
	      a "pure" GPT with a conventional protective MBR.


       o      Print protective MBR data. You can see a summary of the  protec-
	      tive  MBR's  partitions with this option. This may enable you to
	      spot glaring problems or	help  identify	the  partitions	 in  a
	      hybrid MBR.


       p      Print  the  partition table. This option is identical to the 'p'
	      option in the main menu.


       q      Quit without saving changes. This option is identical to the 'q'
	      option in the main menu.


       r      Enter  the recovery & transformations menu. This option is iden-
	      tical to the 'r' option on the main menu.


       s      Resize partition table. The default partition table size is  128
	      entries.	 Officially,  sizes  of	 less  than 16KB (128 entries,
	      given the normal entry size) are unsupported by the GPT specifi-
	      cation;  however,	 in  practice they seem to work, and can some-
	      times be useful in converting MBR disks. Larger sizes also  work
	      fine.  OSes  may impose their own limits on the number of parti-
	      tions, though.


       t      Swap two partitions' entries in the partition table. One	parti-
	      tion  may be empty. For instance, if partitions 1-4 are defined,
	      transposing 1 and 5 results in a table with partitions  numbered
	      from  2-5.  Transposing  partitions in this way has no effect on
	      their disk space allocation; it only alters their order  in  the
	      partition table.


       u      Replicate	 the  current  device's	 partition  table  on  another
	      device. You will be prompted to type the new device's  filename.
	      After  the  write	 operation completes, you can continue editing
	      the original device's partition table.  Note that the replicated
	      partition	 table	is  an exact copy, including all GUIDs; if the
	      device should have its own unique GUIDs, you should  use	the  f
	      option on the new disk.


       v      Verify  disk.  This option is identical to the 'v' option in the
	      main menu.


       z      Zap (destroy) the GPT data structures and exit. Use this	option
	      if  you want to repartition a GPT disk using fdisk or some other
	      GPT-unaware program.  You'll be given the choice	of  preserving
	      the  existing  MBR,  in  case it's a hybrid MBR with salvageable
	      partitions or if you've already created new MBR  partitions  and
	      want  to	erase  the  remnants of your GPT partitions. If you've
	      already created new MBR partitions, it's conceivable  that  this
	      option will damage the first and/or last MBR partitions! Such an
	      event is unlikely, but could occur if your  new  MBR  partitions
	      overlap the old GPT data structures.


       ?      Print the menu. This option (or any unrecognized entry) displays
	      a summary of the menu options.


       In many cases, you can press the Enter key to select a  default	option
       when  entering  data.  When  only one option is possible, gdisk usually
       bypasses the prompt entirely.


BUGS
       As of March 2014 (version 0.8.10),  gdisk  should  be  considered  beta
       software. Known bugs and limitations include:


       *      The program compiles correctly only on Linux, FreeBSD, Mac OS X,
	      and Windows.  Linux versions for x86-64 (64-bit), x86  (32-bit),
	      and  PowerPC  (32-bit) have been tested, with the x86-64 version
	      having seen the most testing. Under FreeBSD,  32-bit  (x86)  and
	      64-bit  (x86-64) versions have been tested. Only 32-bit versions
	      for Mac OS X  and	 Windows  have	been  tested  by  the  author,
	      although	I've  heard of 64-bit versions being successfully com-
	      piled.


       *      The FreeBSD version of the program can't write  changes  to  the
	      partition	 table to a disk when existing partitions on that disk
	      are mounted. (The same problem exists with  many	other  FreeBSD
	      utilities,  such	as gpt, fdisk, and dd.) This limitation can be
	      overcome by typing sysctl	 kern.geom.debugflags=16  at  a	 shell
	      prompt.


       *      The  fields used to display the start and end sector numbers for
	      partitions in the 'p'  command  are  14  characters  wide.  This
	      translates to a limitation of about 45 PiB. On larger disks, the
	      displayed columns will go out of alignment.


       *      In the Windows version, only ASCII characters are	 supported  in
	      the   partition  name  field.  If	 an  existing  partition  uses
	      non-ASCII UTF-16 characters, they're likely to be	 corrupted  in
	      the  'i' and 'p' menu options' displays; however, they should be
	      preserved when  loading  and  saving  partitions.	 Binaries  for
	      Linux, FreeBSD, and OS X support full UTF-16 partition names.


       *      The program can load only up to 128 partitions (4 primary parti-
	      tions and 124 logical partitions) when converting from MBR  for-
	      mat.   This   limit  can	be  raised  by	changing  the  #define
	      MAX_MBR_PARTS line in the basicmbr.h source code file and recom-
	      piling;	however,   such	  a   change   will  require  using  a
	      larger-than-normal partition table. (The limit of 128 partitions
	      was  chosen  because  that number equals the 128 partitions sup-
	      ported by the most common partition table size.)


       *      Converting from MBR format sometimes fails because  of  insuffi-
	      cient space at the start or (more commonly) the end of the disk.
	      Resizing the partition  table  (using  the  's'  option  in  the
	      experts'	menu) can sometimes overcome this problem; however, in
	      extreme cases it may be necessary to resize  a  partition	 using
	      GNU Parted or a similar tool prior to conversion with gdisk.


       *      MBR  conversions work only if the disk has correct LBA partition
	      descriptors. These descriptors should be	present	 on  any  disk
	      over  8 GiB in size or on smaller disks partitioned with any but
	      very ancient software.


       *      BSD disklabel support can create first  and/or  last  partitions
	      that overlap with the GPT data structures. This can sometimes be
	      compensated by  adjusting	 the  partition	 table	size,  but  in
	      extreme cases the affected partition(s) may need to be deleted.


       *      Because  of  the	highly variable nature of BSD disklabel struc-
	      tures, conversions from this form may be	unreliable  --	parti-
	      tions  may  be dropped, converted in a way that creates overlaps
	      with other partitions, or converted with incorrect start or  end
	      values. Use this feature with caution!


       *      Booting  after converting an MBR or BSD disklabel disk is likely
	      to be disrupted. Sometimes re-installing a boot loader will  fix
	      the  problem,  but other times you may need to switch boot load-
	      ers. Except on EFI-based platforms,  Windows  through  at	 least
	      Windows  7  doesn't  support  booting from GPT disks. Creating a
	      hybrid MBR (using the 'h' option on the recovery	&  transforma-
	      tion  menu)  or  abandoning GPT in favor of MBR may be your only
	      options in this case.


AUTHORS
       Primary author: Roderick W. Smith (rodsmith@rodsbooks.com)

       Contributors:

       * Yves Blusseau (1otnwmz02@sneakemail.com)

       * David Hubbard (david.c.hubbard@gmail.com)

       * Justin Maggard (justin.maggard@netgear.com)

       * Dwight Schauer (dschauer@ti.com)

       * Florian Zumbiehl (florz@florz.de)



SEE ALSO
       cfdisk (8), cgdisk (8), fdisk (8), mkfs (8),  parted  (8),  sfdisk  (8)
       sgdisk (8) fixparts (8)

       http://en.wikipedia.org/wiki/GUID_Partition_Table

       http://developer.apple.com/technotes/tn2006/tn2166.html

       http://www.rodsbooks.com/gdisk/


AVAILABILITY
       The  gdisk  command  is	part of the GPT fdisk package and is available
       from Rod Smith.



Roderick W. Smith		    0.8.10			      GDISK(8)
-------------------------------------------------------------------------------------
SGDISK(8)		       GPT fdisk Manual			     SGDISK(8)



NAME
       sgdisk  - Command-line GUID partition table (GPT) manipulator for Linux
       and Unix

SYNOPSIS
       sgdisk [ options ] device


DESCRIPTION
       GPT fdisk is a text-mode menu-driven package for creation and manipula-
       tion  of	 partition  tables. It consists of two programs: the text-mode
       interactive gdisk and the  command-line	sgdisk.	 Either	 program  will
       automatically  convert  an old-style Master Boot Record (MBR) partition
       table or BSD disklabel stored without an MBR carrier partition  to  the
       newer  Globally	Unique Identifier (GUID) Partition Table (GPT) format,
       or will load a GUID partition table. This man page documents  the  com-
       mand-line sgdisk program.

       Some  advanced  data  manipulation  and recovery options require you to
       understand the distinctions between the main and backup data,  as  well
       as between the GPT headers and the partition tables. For information on
       MBR vs. GPT, as well as GPT terminology and structure, see the extended
       gdisk   documentation  at  http://www.rodsbooks.com/gdisk/  or  consult
       Wikipedia.

       The sgdisk program employs a user interface that's  based  entirely  on
       the  command  line, making it suitable for use in scripts or by experts
       who want to make one or two quick changes to a disk. (The  program  may
       query  the  user when certain errors are encountered, though.) The pro-
       gram's name is based on sfdisk, but the user options of	the  two  pro-
       grams are entirely different from one another.

       Ordinarily,  sgdisk  operates on disk device files, such as /dev/sda or
       /dev/hda under Linux,  /dev/disk0  under	 Mac  OS  X,  or  /dev/ad0  or
       /dev/da0	 under	FreeBSD.  The  program	can also operate on disk image
       files, which can be either copies of whole disks	 (made	with  dd,  for
       instance)  or raw disk images used by emulators such as QEMU or VMWare.
       Note that only raw disk images are supported;  sgdisk  cannot  work  on
       compressed or other advanced disk image formats.

       The  MBR partitioning system uses a combination of cylinder/head/sector
       (CHS) addressing and logical block  addressing  (LBA).  The  former  is
       klunky  and limiting. GPT drops CHS addressing and uses 64-bit LBA mode
       exclusively. Thus, GPT data structures, and therefore  sgdisk,  do  not
       need to deal with CHS geometries and all the problems they create.

       For best results, you should use an OS-specific partition table program
       whenever possible. For example, you should make	Mac  OS	 X  partitions
       with  the  Mac  OS X Disk Utility program and Linux partitions with the
       Linux gdisk, sgdisk, or GNU Parted programs.

       Upon start, sgdisk attempts to identify the partition type  in  use  on
       the  disk.  If  it  finds valid GPT data, sgdisk will use it. If sgdisk
       finds a valid MBR or BSD disklabel but no GPT data, it will attempt  to
       convert	the MBR or disklabel into GPT form. (BSD disklabels are likely
       to have unusable first and/or final  partitions	because	 they  overlap
       with  the GPT data structures, though.) GPT fdisk can identify, but not
       use data in, Apple Partition Map (APM) disks, which are used on	680x0-
       and  PowerPC-based  Macintoshes. If you specify any option that results
       in changes to an MBR or BSD disklabel,  sgdisk  ignores	those  changes
       unless  the  -g	(--mbrtogpt),  -z (--zap), or -Z (--zap-all) option is
       used. If you use the -g option, sgdisk replaces the  MBR	 or  disklabel
       with  a	GPT.  This  action  is	potentially dangerous! Your system may
       become unbootable, and partition type codes may become corrupted if the
       disk  uses  unrecognized	 type  codes.  Boot  problems are particularly
       likely if you're multi-booting with any GPT-unaware OS.

       The MBR-to-GPT conversion will leave at least one gap in the  partition
       numbering  if  the original MBR used logical partitions. These gaps are
       harmless, but you can eliminate them by using the -s  (--sort)  option,
       if  you	like.  (Doing  this  may require you to update your /etc/fstab
       file.)

       When creating a fresh partition table, certain considerations may be in
       order:


       *      For data (non-boot) disks, and for boot disks used on BIOS-based
	      computers with GRUB as the boot loader, partitions may  be  cre-
	      ated in whatever order and in whatever sizes are desired.


       *      Boot disks for EFI-based systems require an EFI System Partition
	      (sgdisk internal code 0xEF00) formatted as FAT-32.   The	recom-
	      mended  size  of	this  partition	 is  between  100 and 300 MiB.
	      Boot-related files are stored here. (Note that GNU Parted	 iden-
	      tifies such partitions as having the "boot flag" set.)


       *      Some boot loaders for BIOS-based systems make use of a BIOS Boot
	      Partition (sgdisk internal code 0xEF02), in which the  secondary
	      boot  loader  is	stored,	 possibly  without  the	 benefit  of a
	      filesystem. This partition can typically be quite small (roughly
	      32 to 200 KiB), but you should consult your boot loader documen-
	      tation for details.


       *      If Windows is to boot from a GPT disk, a partition of  type  Mi-
	      crosoft  Reserved	 (sgdisk internal code 0x0C01) is recommended.
	      This partition should be about 128 MiB in	 size.	It  ordinarily
	      follows  the  EFI	 System Partition and immediately precedes the
	      Windows data partitions. (Note that GNU Parted creates  all  FAT
	      partitions  as  this  type,  which  actually makes the partition
	      unusable for normal file storage in both Windows and Mac OS X.)


       *      Some OSes' GPT utilities create some blank space (typically  128
	      MiB)  after  each partition. The intent is to enable future disk
	      utilities to use this space. Such free space is not required  of
	      GPT disks, but creating it may help in future disk maintenance.


OPTIONS
       Some  options  take no arguments, others take one argument (typically a
       partition number), and others take compound arguments with colon delim-
       itation.	 For instance, -n (--new) takes a partition number, a starting
       sector  number,	and  an	 ending	 sector	 number,  as  in   sgdisk   -n
       2:2000:50000  /dev/sdc,	which  creates	a  new	partition, numbered 2,
       starting at sector 2000 an ending at sector 50,000, on /dev/sdc.

       Unrelated options may be combined; however, some such combinations will
       be  nonsense  (such  as deleting a partition and then changing its GUID
       type code).  sgdisk interprets options in the order  in	which  they're
       entered,	 so  effects can vary depending on order. For instance, sgdisk
       -s -d 2 sorts the partition table entries and then deletes partition  2
       from  the  newly-sorted	list;  but sgdisk -d 2 -s deletes the original
       partition 2 and then sorts the modified partition table.

       Error checking and opportunities to correct mistakes in sgdisk are min-
       imal.  Although	the  program endeavors to keep the GPT data structures
       legal, it does  not  prompt  for	 verification  before  performing  its
       actions.	 Unless	 you require a command-line-driven program, you should
       use the interactive gdisk instead of sgdisk, since gdisk allows you  to
       quit without saving your changes, should you make a mistake.

       Although	 sgdisk	 is  based  on the same partition-manipulation code as
       gdisk, sgdisk implements fewer features than its	 interactive  sibling.
       Options available in sgdisk are:


       -a, --set-alignment=value
	      Set the sector alignment multiple. GPT fdisk aligns the start of
	      partitions to sectors that are multiples of  this	 value,	 which
	      defaults	to  2048  on  freshly  formatted disks. This alignment
	      value is necessary to obtain optimum  performance	 with  Western
	      Digital  Advanced Format and similar drives with larger physical
	      than logical sector sizes, with some types of RAID  arrays,  and
	      with SSD devices.


       -A,	  --attributes=list|[partnum:show|or|nand|xor|=|set|clear|tog-
       gle|get[:bitnum|hexbitmask]]
	      View or set  partition  attributes.  Use	list  to  see  defined
	      (known)  attribute  values.  Omit the partition number (and even
	      the device filename) when using this option. The others  require
	      a	 partition  number.  The show and get options show the current
	      attribute settings (all attributes  or  for  a  particular  bit,
	      respectively).  The  or,	nand,  xor,  =, set, clear, and toggle
	      options enable you to change the attribute bit value.  The  set,
	      clear,  toggle, and get options work on a bit number; the others
	      work on a hexadecimal bit mask.  For  example,  type  sgdisk  -A
	      4:set:2  /dev/sdc	 to  set  the  bit  2  attribute  (legacy BIOS
	      bootable) on partition 4 on /dev/sdc.


       -b, --backup=file
	      Save partition data to a backup file. You can back up your  cur-
	      rent in-memory partition table to a disk file using this option.
	      The resulting file is a binary file consisting of the protective
	      MBR, the main GPT header, the backup GPT header, and one copy of
	      the partition table, in that order. Note that the backup	is  of
	      the current in-memory data structures, so if you launch the pro-
	      gram, make changes, and then use this option,  the  backup  will
	      reflect  your  changes.  If the GPT data structures are damaged,
	      the  backup  may	not  accurately	 reflect  the  damaged	state;
	      instead, they will reflect GPT fdisk's first-pass interpretation
	      of the GPT.


       -c, --change-name=partnum:name
	      Change the GPT name of a partition. This name is	encoded	 as  a
	      UTF-16  string,  but proper entry and display of anything beyond
	      basic ASCII values requires suitable locale  and	font  support.
	      For  the most part, Linux ignores the partition name, but it may
	      be important in some OSes. If  you  want	to  set	 a  name  that
	      includes a space, enclose it in quotation marks, as in sgdisk -c
	      1:"Sample Name" /dev/sdb. Note that the GPT name of a  partition
	      is  distinct  from  the filesystem name, which is encoded in the
	      filesystem's data structures.


       -C, --recompute-chs
	      Recompute CHS values in protective or hybrid  MBR.  This	option
	      can  sometimes  help if a disk utility, OS, or BIOS doesn't like
	      the CHS values used by  the  partitions  in  the	protective  or
	      hybrid  MBR. In particular, the GPT specification requires a CHS
	      value of 0xFFFFFF for over-8GiB partitions, but  this  value  is
	      technically  illegal by the usual standards. Some BIOSes hang if
	      they encounter this value. This option  will  recompute  a  more
	      normal  CHS value -- 0xFEFFFF for over-8GiB partitions, enabling
	      these BIOSes to boot.


       -d, --delete=partnum
	      Delete a partition. This action deletes the entry from the  par-
	      tition  table  but  does not disturb the data within the sectors
	      originally allocated to the partition on the disk. If  a	corre-
	      sponding hybrid MBR partition exists, gdisk deletes it, as well,
	      and expands any adjacent 0xEE (EFI GPT) MBR protective partition
	      to fill the new free space.


       -D, --display-alignment
	      Display  current sector alignment value. Partitions will be cre-
	      ated on multiples of the sector value reported by	 this  option.
	      You can change the alignment value with the -a option.


       e, --move-second-header
	      Move backup GPT data structures to the end of the disk. Use this
	      option if you've added disks to a RAID array,  thus  creating  a
	      virtual  disk with space that follows the backup GPT data struc-
	      tures. This command moves the backup GPT data structures to  the
	      end of the disk, where they belong.


       -E, --end-of-largest
	      Displays	the  sector number of the end of the largest available
	      block of sectors on the disk. A script may store this value  and
	      pass it back as part of -n's option to create a partition. If no
	      unallocated sectors are available,  this	function  returns  the
	      value 0.


       -f, --first-in-largest
	      Displays the sector number of the start of the largest available
	      block of sectors on the disk. A script may store this value  and
	      pass it back as part of -n's option to create a partition. If no
	      unallocated sectors are available,  this	function  returns  the
	      value  0.	 Note that this parameter is blind to partition align-
	      ment; when you actually create  a	 partition,  its  start	 point
	      might be changed from this value.


       -F, --first-aligned-in-largest
	      Similar  to  -f  (--first-in-largest), except returns the sector
	      number with the current alignment correction applied.  Use  this
	      function if you need to compute the actual partition start point
	      rather than a theoretical start point or the actual start	 point
	      if you set the alignment value to 1.


       -g, --mbrtogpt
	      Convert  an MBR or BSD disklabel disk to a GPT disk. As a safety
	      measure, use of this option is required on MBR or BSD  disklabel
	      disks  if	 you  intend to save your changes, in order to prevent
	      accidentally damaging such disks.


       -G, --randomize-guids
	      Randomize the disk's GUID and all partitions' unique GUIDs  (but
	      not  their partition type code GUIDs). This function may be used
	      after cloning a disk in order to render  all  GUIDs  once	 again
	      unique.


       -h, --hybrid
	      Create  a hybrid MBR. This option takes from one to three parti-
	      tion numbers, separated by colons,  as  arguments.  The  created
	      hybrid  MBR places an EFI GPT (type 0xEE) partition first in the
	      table, followed by the  partition(s)  you	 specify.  Their  type
	      codes  are  based on the GPT fdisk type codes divided by 0x0100,
	      which  is	 usually  correct  for	Windows	 partitions.  If   the
	      active/bootable  flag  should  be set, you must do so in another
	      program, such as fdisk.  The  gdisk  program  offers  additional
	      hybrid MBR creation options.


       -i, --info=partnum
	      Show  detailed  partition	 information.  The summary information
	      produced by the -p command necessarily omits many details,  such
	      as  the  partition's unique GUID and the translation of sgdisk's
	      internal partition type code to a plain type name. The -i option
	      displays this information for a single partition.


       -l, --load-backup=file
	      Load  partition  data  from  a  backup  file. This option is the
	      reverse of the -b option. Note  that  restoring  partition  data
	      from  anything  but  the	original disk is not recommended. This
	      option will work even if the disk's original partition table  is
	      bad;  however,  most other options on the same command line will
	      be ignored.


       -L, --list-types
	      Display a summary of partition types. GPT uses a GUID  to	 iden-
	      tify  partition types for particular OSes and purposes. For ease
	      of data entry, sgdisk compresses these into two-byte (four-digit
	      hexadecimal)  values  that  are  related to their equivalent MBR
	      codes. Specifically, the MBR code is multiplied  by  hexadecimal
	      0x0100.  For  instance,  the code for Linux swap space in MBR is
	      0x82, and it's 0x8200 in gdisk. A one-to-one  correspondence  is
	      impossible, though. Most notably, the codes for all varieties of
	      FAT and NTFS partition correspond to a single GPT code  (entered
	      as 0x0700 in sgdisk). Some OSes use a single MBR code but employ
	      many more codes in GPT. For  these,  sgdisk  adds	 code  numbers
	      sequentially, such as 0xa500 for a FreeBSD disklabel, 0xa501 for
	      FreeBSD boot, 0xa502 for FreeBSD swap,  and  so  on.  Note  that
	      these two-byte codes are unique to gdisk and sgdisk. This option
	      does not require you to specify a valid disk device filename.


       -m, --gpttombr
	      Convert disk from GPT to MBR form. This option takes from one to
	      four partition numbers, separated by colons, as arguments. Their
	      type codes are based on the GPT  fdisk  type  codes  divided  by
	      0x0100.  If  the active/bootable flag should be set, you must do
	      so in another program, such as fdisk.  The gdisk program	offers
	      additional MBR conversion options. It is not possible to convert
	      more than four partitions from GPT to MBR	 form  or  to  convert
	      partitions  that	start  above  the 2TiB mark or that are larger
	      than 2TiB.


       -n, --new=partnum:start:end
	      Create a new partition. You enter a partition  number,  starting
	      sector,  and an ending sector. Both start and end sectors can be
	      specified in absolute terms as sector numbers  or	 as  positions
	      measured	 in  kibibytes	(K),  mebibytes	 (M),  gibibytes  (G),
	      tebibytes (T), or pebibytes (P); for instance, 40M  specifies  a
	      position 40MiB from the start of the disk. You can specify loca-
	      tions relative to the start or  end  of  the  specified  default
	      range  by preceding the number by a '+' or '-' symbol, as in +2G
	      to specify a point 2GiB after the default start sector, or -200M
	      to  specify  a  point 200MiB before the last available sector. A
	      start or end value of 0 specifies the default  value,  which  is
	      the  start  of  the largest available block for the start sector
	      and the end of the same block for	 the  end  sector.  A  partnum
	      value  of 0 causes the program to use the first available parti-
	      tion number. Subsequent uses of the -A, -c, -t, and  -u  options
	      may also use 0 to refer to the same partition.


       -N, --largest-new=num
	      Create a new partition that fills the largest available block of
	      space on the disk. Note that if used on a completely blank disk,
	      this  is	likely	to result in a sector-moved warning, since the
	      first available sector (normally 34) doesn't fall on a 2048-sec-
	      tor  boundary  (the  default  for alignment). You can use the -a
	      (--set-alignment) option to adjust the alignment, if desired.  A
	      num  value  of  0	 causes the program to use the first available
	      partition number.


       -o, --clear
	      Clear out all partition data. This includes GPT header data, all
	      partition	 definitions,  and  the protective MBR. Note that this
	      operation will, like most other operations, fail	on  a  damaged
	      disk.  If	 you want to prepare a disk you know to be damaged for
	      GPT use, you should first wipe it with -Z and then partition  it
	      normally. This option will work even if the disk's original par-
	      tition table is bad; however, most other	options	 on  the  same
	      command line will be ignored.


       -p, --print
	      Display  basic  partition	 summary data. This includes partition
	      numbers, starting and ending sector  numbers,  partition	sizes,
	      sgdisk's	partition  types codes, and partition names. For addi-
	      tional information, use the -i (--info) option.


       -P, --pretend
	      Pretend to make specified changes. In-memory GPT data structures
	      are  altered  according to other parameters, but changes are not
	      written to disk.


       -r, --transpose
	      Swap two partitions' entries in the partition table. One or both
	      partitions  may be empty, although swapping two empty partitions
	      is pointless. For	 instance,  if	partitions  1-4	 are  defined,
	      transposing  1 and 5 results in a table with partitions numbered
	      from 2-5. Transposing partitions in this way has	no  effect  on
	      their  disk  space allocation; it only alters their order in the
	      partition table.


       -R, --replicate=second_device_filename
	      Replicate the main device's partition  table  on	the  specified
	      second  device.	Note that the replicated partition table is an
	      exact copy, including all GUIDs; if the device should  have  its
	      own unique GUIDs, you should use the -G option on the new disk.


       -s, --sort
	      Sort partition entries. GPT partition numbers need not match the
	      order of partitions on the disk. If you want them to match,  you
	      can use this option.  Note that some partitioning utilities sort
	      partitions whenever they make  changes.  Such  changes  will  be
	      reflected	 in  your  device  filenames,  so you may need to edit
	      /etc/fstab if you use this option.


       -t, --typecode=partnum:{hexcode|GUID}
	      Change a single partition's type code. You enter the  type  code
	      using  either  a	two-byte hexadecimal number, as described ear-
	      lier,   or   a   fully-specified	  GUID	  value,    such    as
	      EBD0A0A2-B9E5-4433-87C0-68B6B72699C7.


       -T, --transform-bsd=partnum
	      Transform	 BSD partitions into GPT partitions. This option works
	      on BSD disklabels held within GPT (or converted MBR) partitions.
	      Converted	 partitions'  type  codes  are	likely	to need manual
	      adjustment. sgdisk will attempt to convert BSD disklabels stored
	      on the main disk when launched, but this conversion is likely to
	      produce first and/or last partitions that are unusable. The many
	      BSD  variants  means that the probability of sgdisk being unable
	      to convert a BSD disklabel is high compared to the likelihood of
	      problems with an MBR conversion.


       -u, --partition-guid=partnum:guid
	      Set  the	partition unique GUID for an individual partition. The
	      GUID may be a complete GUID or 'R' to set a random GUID.


       -U, --disk-guid=guid
	      Set the GUID for the disk. The GUID may be a  complete  GUID  or
	      'R' to set a random GUID.


       --usage
	      Print a brief summary of available options.


       -v, --verify
	      Verify  disk. This option checks for a variety of problems, such
	      as incorrect CRCs and mismatched	main  and  backup  data.  This
	      option does not automatically correct most problems, though; for
	      that, you must use options  on  the  recovery  &	transformation
	      menu.  If no problems are found, this command displays a summary
	      of unallocated disk space. This option will  work	 even  if  the
	      disk's  original	partition  table  is  bad; however, most other
	      options on the same command line will be ignored.


       -V, --version
	      Display program version information. This	 option	 may  be  used
	      without specifying a device filename.


       -z, --zap
	      Zap  (destroy)  the  GPT data structures and then exit. Use this
	      option if you want to repartition a GPT disk using fdisk or some
	      other  GPT-unaware  program.  This  option destroys only the GPT
	      data structures; it leaves the MBR intact. This makes it	useful
	      for  wiping out GPT data structures after a disk has been repar-
	      titioned for MBR using a GPT-unaware utility; however, there's a
	      risk  that  it will damage boot loaders or even the start of the
	      first or end of the last MBR partition. If you use it on a valid
	      GPT  disk,  the  MBR  will be left with an inappropriate EFI GPT
	      (0xEE) partition definition, which you can delete using  another
	      utility.


       -Z, --zap-all
	      Zap  (destroy)  the  GPT	and MBR data structures and then exit.
	      This option works much like -z, but as it wipes the MBR as  well
	      as the GPT, it's more suitable if you want to repartition a disk
	      after using this option, and  completely	unsuitable  if	you've
	      already repartitioned the disk.


       -?, --help
	      Print a summary of options.


RETURN VALUES
       sgdisk returns various values depending on its success or failure:


       0      Normal program execution


       1      Too few arguments


       2      An error occurred while reading the partition table


       3      Non-GPT disk detected and no -g option


       4      An error prevented saving changes


       5      An  error	 occurred  while  reading standard input (should never
	      occur with sgdisk, but may with gdisk)


       8      Disk replication operation (-R) failed


BUGS
       As of March 2014 (version 0.8.10), sgdisk  should  be  considered  beta
       software. Known bugs and limitations include:


       *      The  program  compiles correctly only on Linux, FreeBSD, and Mac
	      OS X. Linux versions for x86-64 (64-bit), x86 (32-bit), and Pow-
	      erPC  (32-bit)  have been tested, with the x86-64 version having
	      seen the most testing.


       *      The FreeBSD version of the program can't write  changes  to  the
	      partition	 table to a disk when existing partitions on that disk
	      are mounted. (The same problem exists with  many	other  FreeBSD
	      utilities,  such	as gpt, fdisk, and dd.) This limitation can be
	      overcome by typing sysctl	 kern.geom.debugflags=16  at  a	 shell
	      prompt.


       *      The  fields used to display the start and end sector numbers for
	      partitions in the -p option are 14 characters wide. This	trans-
	      lates to a limitation of about 45 PiB. On larger disks, the dis-
	      played columns will go out of alignment.


       *      The program can load only up to 128 partitions (4 primary parti-
	      tions  and 124 logical partitions) when converting from MBR for-
	      mat.  This  limit	 can  be  raised  by  changing	 the   #define
	      MAX_MBR_PARTS line in the basicmbr.h source code file and recom-
	      piling;  however,	 such  a   change   will   require   using   a
	      larger-than-normal partition table. (The limit of 128 partitions
	      was chosen because that number equals the	 128  partitions  sup-
	      ported by the most common partition table size.)


       *      Converting  from	MBR format sometimes fails because of insuffi-
	      cient space at the start or (more commonly) the end of the disk.
	      Resizing	the  partition	table  (using  the  's'	 option in the
	      experts' menu) can sometimes overcome this problem; however,  in
	      extreme  cases  it  may be necessary to resize a partition using
	      GNU Parted or a similar tool prior to conversion with gdisk.


       *      MBR conversions work only if the disk has correct LBA  partition
	      descriptors.  These  descriptors	should	be present on any disk
	      over 8 GiB in size or on smaller disks partitioned with any  but
	      very ancient software.


       *      BSD  disklabel  support  can create first and/or last partitions
	      that overlap with the GPT data structures. This can sometimes be
	      compensated  by  adjusting  the  partition  table	 size,	but in
	      extreme cases the affected partition(s) may need to be deleted.


       *      Because of the highly variable nature of	BSD  disklabel	struc-
	      tures,  conversions  from	 this form may be unreliable -- parti-
	      tions may be dropped, converted in a way that  creates  overlaps
	      with  other partitions, or converted with incorrect start or end
	      values. Use this feature with caution!


       *      Booting after converting an MBR or BSD disklabel disk is	likely
	      to  be disrupted. Sometimes re-installing a boot loader will fix
	      the problem, but other times you may need to switch  boot	 load-
	      ers.  Except  on	EFI-based  platforms, Windows through at least
	      Windows 7 RC doesn't support booting from GPT disks. Creating  a
	      hybrid  MBR  (using the 'h' option on the recovery & transforma-
	      tion menu) or abandoning GPT in favor of MBR may	be  your  only
	      options in this case.


AUTHORS
       Primary author: Roderick W. Smith (rodsmith@rodsbooks.com)

       Contributors:

       * Yves Blusseau (1otnwmz02@sneakemail.com)

       * David Hubbard (david.c.hubbard@gmail.com)

       * Justin Maggard (justin.maggard@netgear.com)

       * Dwight Schauer (dschauer@ti.com)

       * Florian Zumbiehl (florz@florz.de)



SEE ALSO
       cfdisk  (8),  cgdisk  (8),  fdisk (8), gdisk (8), mkfs (8), parted (8),
       sfdisk (8) fixparts (8)

       http://en.wikipedia.org/wiki/GUID_Partition_Table

       http://developer.apple.com/technotes/tn2006/tn2166.html

       http://www.rodsbooks.com/gdisk/


AVAILABILITY
       The sgdisk command is part of the GPT fdisk package  and	 is  available
       from Rod Smith.



Roderick W. Smith		    0.8.10			     SGDISK(8)
-------------------------------------------------------------------------------------
CGDISK(8)		       GPT fdisk Manual			     CGDISK(8)



NAME
       cgdisk - Curses-based GUID partition table (GPT) manipulator

SYNOPSIS
       cgdisk [ -a ] device


DESCRIPTION
       GPT  fdisk is a text-mode family of programs for creation and manipula-
       tion of partition tables. The cgdisk member of this  family  employs  a
       curses-based  user  interface for interaction using a text-mode menuing
       system. It will automatically convert an old-style Master  Boot	Record
       (MBR)  partition	 table	or BSD disklabel stored without an MBR carrier
       partition to the newer Globally Unique Identifier (GUID) Partition  Ta-
       ble (GPT) format, or will load a GUID partition table. Other members of
       this program family are gdisk (the most	feature-rich  program  of  the
       group,  with  a non-curses-based interactive user interface) and sgdisk
       (which is driven via command-line options for  use  by  experts	or  in
       scripts).   FixParts  is	 a related program for fixing a limited set of
       problems with MBR disks.

       For information on MBR vs. GPT, as well as GPT terminology  and	struc-
       ture,  see  the	extended  GPT  fdisk documentation at http://www.rods-
       books.com/gdisk/ or consult Wikipedia.

       The cgdisk program employs a user interface similar to that of  Linux's
       cfdisk,	but cgdisk modifies GPT partitions. It also has the capability
       of transforming MBR partitions or BSD disklabels into  GPT  partitions.
       Like  the  original  cfdisk program, cgdisk does not modify disk struc-
       tures until you explicitly write them to disk, so if you	 make  a  mis-
       take,  you can exit from the program with the Quit option to leave your
       partitions unmodified.

       Ordinarily, cgdisk operates on disk device files, such as  /dev/sda  or
       /dev/hda	 under	Linux,	/dev/disk0  under  Mac	OS  X,	or /dev/ad0 or
       /dev/da0 under FreeBSD. The program can	also  operate  on  disk	 image
       files,  which  can  be  either copies of whole disks (made with dd, for
       instance) or raw disk images used by emulators such as QEMU or  VMWare.
       Note  that  only	 raw  disk images are supported; cgdisk cannot work on
       compressed or other advanced disk image formats.

       Upon start, cgdisk attempts to identify the partition type  in  use  on
       the  disk.  If  it  finds valid GPT data, cgdisk will use it. If cgdisk
       finds a valid MBR or BSD disklabel but no GPT data, it will attempt  to
       convert	the MBR or disklabel into GPT form. (BSD disklabels are likely
       to have unusable first and/or final  partitions	because	 they  overlap
       with  the  GPT  data  structures,  though.)  Upon  exiting with the 'w'
       option, cgdisk replaces the MBR or disklabel with a GPT. This action is
       potentially dangerous! Your system may become unbootable, and partition
       type codes may become corrupted if  the	disk  uses  unrecognized  type
       codes.	Boot  problems are particularly likely if you're multi-booting
       with any GPT-unaware OS. If you mistakenly  launch  cgdisk  on  an  MBR
       disk,  you  can	safely	exit the program without making any changes by
       using the Quit option.

       When creating a fresh partition table, certain considerations may be in
       order:


       *      For data (non-boot) disks, and for boot disks used on BIOS-based
	      computers with GRUB as the boot loader, partitions may  be  cre-
	      ated in whatever order and in whatever sizes are desired.


       *      Boot disks for EFI-based systems require an EFI System Partition
	      (GPT fdisk internal code 0xEF00) formatted as FAT-32.  The  rec-
	      ommended	size  of  this	partition  is between 100 and 300 MiB.
	      Boot-related files are stored here. (Note that GNU Parted	 iden-
	      tifies such partitions as having the "boot flag" set.)


       *      The  GRUB	 2  boot  loader for BIOS-based systems makes use of a
	      BIOS Boot Partition (GPT fdisk internal code 0xEF02),  in	 which
	      the  secondary  boot  loader is stored, without the benefit of a
	      filesystem. This partition can typically be quite small (roughly
	      32  KiB to 1 MiB), but you should consult your boot loader docu-
	      mentation for details.


       *      If Windows is to boot from a GPT disk, a partition of  type  Mi-
	      crosoft  Reserved	 (GPT  fdisk  internal	code 0x0C01) is recom-
	      mended. This partition should be about 128 MiB in size. It ordi-
	      narily follows the EFI System Partition and immediately precedes
	      the Windows data partitions. (Note  that	old  versions  of  GNU
	      Parted  create  all  FAT partitions as this type, which actually
	      makes the partition unusable for normal  file  storage  in  both
	      Windows and Mac OS X.)


       *      Some  OSes' GPT utilities create some blank space (typically 128
	      MiB) after each partition. The intent is to enable  future  disk
	      utilities	 to use this space. Such free space is not required of
	      GPT disks, but creating it may help in future disk  maintenance.
	      You  can	use  GPT fdisk's relative partition positioning option
	      (specifying the starting sector as  '+128M',  for	 instance)  to
	      simplify creating such gaps.


OPTIONS
       Only  one  command-line option is accepted, aside from the device file-
       name: -a. This option alters the highlighting of partitions and	blocks
       of  free space: Instead of using ncurses, when -a is used cgdisk uses a
       ">" symbol to the left of the selected partition or free	 space.	  This
       option is intended for use on limited display devices such as teletypes
       and screen readers.

       Interactions with cgdisk occur with its	interactive  text-mode	menus.
       The display is broken into two interactive parts:


       *      The partition display area, in which partitions and gaps between
	      them (marked as "free space") are summarized.


       *      The option selection area, in which buttons for the main options
	      appear.


       In  addition,  the top of the display shows the program's name and ver-
       sion number, the device filename associated  with  the  disk,  and  the
       disk's size in both sectors and IEEE-1541 units (GiB, TiB, and so on).

       You can use the following keys to move among the various options and to
       select among them:


       up arrow
	      This key moves the partition selection up by one partition.


       down arrow
	      This key moves the partition selection down by one partition.


       Page Up
	      This key moves the partition selection up by one screen.


       Page Down
	      This key moves the partition selection down by one screen.


       right arrow
	      This key moves the option selection to the right by one item.


       left arrow
	      This key moves the option selection to the left by one item.


       Enter  This key activates the currently selected option. You  can  also
	      activate	an  option  by	typing	the  capitalized letter in the
	      option's name on the keyboard, such as a to activate  the	 Align
	      option.


       If  more	 partitions exist than can be displayed in one screen, you can
       scroll between screens using the partition selection keys, much as in a
       text editor.

       Available  options are as described below. (Note that cgdisk provides a
       much more limited set of options than its sibling gdisk. If you need to
       perform	partition  table  recovery,  hybrid  MBR modifcation, or other
       advanced operations, you should consult the gdisk documentation.)


       Align  Change the sector alignment value. Disks with more logical  sec-
	      tors  than  physical  sectors  (such  as	modern Advanced Format
	      drives), some RAID configurations, and  many  SSD	 devices,  can
	      suffer  performance problems if partitions are not aligned prop-
	      erly for their internal data structures. On new disks, GPT fdisk
	      attempts to align partitions on 2048-sector (1MiB) boundaries by
	      default, which optimizes	performance  for  all  of  these  disk
	      types.  On pre-partitioned disks, GPT fdisk attempts to identify
	      the alignment value used on that disk,  but  will	 set  8-sector
	      alignment	 on  disks larger than 300 GB even if lesser alignment
	      values are detected. In either case, it can be changed by	 using
	      this option.


       Backup Save  partition data to a backup file. You can back up your cur-
	      rent in-memory partition table to a disk file using this option.
	      The resulting file is a binary file consisting of the protective
	      MBR, the main GPT header, the backup GPT header, and one copy of
	      the  partition  table, in that order. Note that the backup is of
	      the current in-memory data structures, so if you launch the pro-
	      gram,  make  changes,  and then use this option, the backup will
	      reflect your changes.


       Delete Delete a partition. This action deletes the entry from the  par-
	      tition  table  but  does not disturb the data within the sectors
	      originally allocated to the partition on the disk. If  a	corre-
	      sponding hybrid MBR partition exists, gdisk deletes it, as well,
	      and expands any adjacent 0xEE (EFI GPT) MBR protective partition
	      to fill the new free space.


       Help   Print brief descriptions of all the options.


       Info   Show  detailed  partition	 information.  The summary information
	      shown in the  partition  display	area  necessarily  omits  many
	      details,	such  as  the  partitions' unique GUIDs and the parti-
	      tions' sector-exact start and end points. The Info  option  dis-
	      plays this information for a single partition.


       Load   Load  partition  data  from  a  backup  file. This option is the
	      reverse of the Backup option. Note that restoring partition data
	      from anything but the original disk is not recommended.


       naMe   Change  the  GPT	name of a partition. This name is encoded as a
	      UTF-16 string, but proper entry and display of  anything	beyond
	      basic  ASCII  values  requires suitable locale and font support.
	      For the most part, Linux ignores the partition name, but it  may
	      be  important  in some OSes. GPT fdisk sets a default name based
	      on the partition type code. Note that the GPT partition name  is
	      different	 from  the  filesystem	name,  which is encoded in the
	      filesystem's data structures. Note also that  to	activate  this
	      item  by	typing	its alphabetic equivalent, you must use M, not
	      the more obvious N, because the  latter  is  used	 by  the  next
	      option....


       New    Create  a	 new partition. You enter a starting sector, a size, a
	      type code, and a name. The start	sector	can  be	 specified  in
	      absolute	terms  as a sector number or as a position measured in
	      kibibytes (K), mebibytes (M), gibibytes (G), tebibytes  (T),  or
	      pebibytes (P); for instance, 40M specifies a position 40MiB from
	      the start of the disk. You can specify locations relative to the
	      start  or	 end  of  the specified default range by preceding the
	      number by a '+' symbol, as in +2G to specify a point 2GiB	 after
	      the default start sector. The size value can use the K, M, G, T,
	      and P suffixes, too. Pressing the Enter key with no input speci-
	      fies the default value, which is the start of the largest avail-
	      able block for the start sector and the full available size  for
	      the size.


       Quit   Quit  from  the  program	without saving your changes.  Use this
	      option if you just wanted to view information or if you  make  a
	      mistake and want to back out of all your changes.


       Type   Change  a	 single partition's type code. You enter the type code
	      using a two-byte hexadecimal number. You may also enter  a  GUID
	      directly,	 if  you  have	one and cgdisk doesn't know it. If you
	      don't know the type code for your partition, you can type	 L  to
	      see a list of known type codes.


       Verify Verify  disk. This option checks for a variety of problems, such
	      as incorrect CRCs and mismatched	main  and  backup  data.  This
	      option does not automatically correct most problems, though; for
	      that, you must use gdisk. If no problems are found, this command
	      displays a summary of unallocated disk space.


       Write  Write data. Use this command to save your changes.


BUGS
       As  of  March  2014  (version 0.8.10), cgdisk should be considered beta
       software. Although the underlying partition manipulation code  is  much
       older,  the  cgdisk  ncurses user interface is brand new with GPT fdisk
       version 0.8.0. Known bugs and limitations include:


       *      The program compiles correctly only on Linux, FreeBSD,  and  Mac
	      OS  X. In theory, it should compile under Windows if the Ncurses
	      library for Windows is installed, but I  have  not  tested  this
	      capability.  Linux  versions  for x86-64 (64-bit), x86 (32-bit),
	      and PowerPC (32-bit) have been tested, with the  x86-64  version
	      having  seen  the	 most testing. Under FreeBSD, 32-bit (x86) and
	      64-bit (x86-64) versions have been tested. Only 32-bit  versions
	      for Mac OS X has been tested by the author.


       *      The  FreeBSD  version  of the program can't write changes to the
	      partition table to a disk when existing partitions on that  disk
	      are  mounted.  (The  same problem exists with many other FreeBSD
	      utilities, such as gpt, fdisk, and dd.) This limitation  can  be
	      overcome	by  typing  sysctl  kern.geom.debugflags=16 at a shell
	      prompt.


       *      The program can load only up to 128 partitions (4 primary parti-
	      tions  and 124 logical partitions) when converting from MBR for-
	      mat.  This  limit	 can  be  raised  by  changing	 the   #define
	      MAX_MBR_PARTS line in the basicmbr.h source code file and recom-
	      piling;  however,	 such  a   change   will   require   using   a
	      larger-than-normal partition table. (The limit of 128 partitions
	      was chosen because that number equals the	 128  partitions  sup-
	      ported by the most common partition table size.)


       *      Converting  from	MBR format sometimes fails because of insuffi-
	      cient space at the start or (more commonly) the end of the disk.
	      Resizing	the  partition	table  (using  the  's'	 option in the
	      experts' menu in gdisk) can  sometimes  overcome	this  problem;
	      however, in extreme cases it may be necessary to resize a parti-
	      tion using GNU Parted or a similar tool prior to conversion with
	      GPT fdisk.


       *      MBR  conversions work only if the disk has correct LBA partition
	      descriptors. These descriptors should be	present	 on  any  disk
	      over  8 GiB in size or on smaller disks partitioned with any but
	      very ancient software.


       *      BSD disklabel support can create first  and/or  last  partitions
	      that overlap with the GPT data structures. This can sometimes be
	      compensated by  adjusting	 the  partition	 table	size,  but  in
	      extreme cases the affected partition(s) may need to be deleted.


       *      Because  of  the	highly variable nature of BSD disklabel struc-
	      tures, conversions from this form may be	unreliable  --	parti-
	      tions  may  be dropped, converted in a way that creates overlaps
	      with other partitions, or converted with incorrect start or  end
	      values. Use this feature with caution!


       *      Booting  after converting an MBR or BSD disklabel disk is likely
	      to be disrupted. Sometimes re-installing a boot loader will  fix
	      the  problem,  but other times you may need to switch boot load-
	      ers. Except on EFI-based platforms,  Windows  through  at	 least
	      Windows  7  doesn't  support  booting from GPT disks. Creating a
	      hybrid MBR (using the 'h' option on the recovery	&  transforma-
	      tion  menu  in  gdisk)  or abandoning GPT in favor of MBR may be
	      your only options in this case.


       *      The cgdisk  Verify  function  and	 the  partition	 type  listing
	      obtainable  by typing L in the Type function (or when specifying
	      a partition type while creating a new partition) both  currently
	      exit  ncurses  mode. This limitation is a minor cosmetic blemish
	      that does not affect functionality.


AUTHORS
       Primary author: Roderick W. Smith (rodsmith@rodsbooks.com)

       Contributors:

       * Yves Blusseau (1otnwmz02@sneakemail.com)

       * David Hubbard (david.c.hubbard@gmail.com)

       * Justin Maggard (justin.maggard@netgear.com)

       * Dwight Schauer (dschauer@ti.com)

       * Florian Zumbiehl (florz@florz.de)



SEE ALSO
       cfdisk (8), fdisk (8), gdisk (8), mkfs  (8),  parted  (8),  sfdisk  (8)
       sgdisk (8) fixparts (8)

       http://en.wikipedia.org/wiki/GUID_Partition_Table

       http://developer.apple.com/technotes/tn2006/tn2166.html

       http://www.rodsbooks.com/gdisk/


AVAILABILITY
       The  cgdisk  command  is part of the GPT fdisk package and is available
       from Rod Smith.



Roderick W. Smith		    0.8.10			     CGDISK(8)
-------------------------------------------------------------------------------------
FIXPARTS(8)			FixParts Manual			   FIXPARTS(8)



NAME
       fixparts - MBR partition table repair utility

SYNOPSIS
       fixparts device


DESCRIPTION
       FixParts	 (aka fixparts) is a text-mode menu-driven program for repair-
       ing certain types of problems with Master Boot Record  (MBR)  partition
       tables.	The  program has three design goals, although a few additional
       features are supported, as well:


       *      It can remove stray GUID Partition Table (GPT) data,  which  can
	      be  left	behind	on a disk that was once used as a GPT disk but
	      then incompletely converted to the more common (as of 2011)  MBR
	      form.


       *      It can repair mis-sized extended partitions -- either partitions
	      that extend beyond the physical end of the disk or that  overlap
	      with  nearby  primary partitions. FixParts is designed in such a
	      way that this type of repair occurs automatically,  so  if  it's
	      the  only problem with your disk, you can launch the program and
	      then immediately save the	 partition  table,  making  no	manual
	      changes, and the program will fix the problem.


       *      You  can	change	primary	 partitions into logical partitions or
	      vice-versa, within constraints imposed by the  MBR  data	struc-
	      tures.


       Additional  features include the ability to change partition type codes
       or boot/active flags, to delete partitions, and to recompute  CHS  val-
       ues.  With the possible exception of recomputing CHS values, these sec-
       ondary features are better  performed  with  fdisk,  because  fixparts'
       design  means  that  it's likely to alter partition numbering even when
       such changes are not requested.

       The fixparts program employs  a	user  interface	 similar  to  that  of
       Linux's fdisk, but fixparts is much more specialized. Most importantly,
       you can't create new partitions with fixparts, although you can	change
       primary/logical assignment.

       In the MBR scheme, partitions come in three varieties:


       primary
	      These  partitions	 are  defined  in the first sector of the hard
	      disk and are limited in number to four. Some OSes, such as  Win-
	      dows and FreeBSD, must boot from a primary partition.


       extended
	      Extended	partitions  are	 specialized  primary partitions. They
	      serve as holding areas for logical partitions.


       logical
	      A disk can contain an arbitrary  number  of  logical  partitions
	      (fixparts,  however, imposes a limit of 124 logical partitions).
	      All the logical partitions reside inside a single extended  par-
	      tition, and are defined using a linked-list data structure. This
	      fact means that every logical partition must be preceded	by  at
	      least  one sector of unallocated space to hold its defining data
	      structure (an Extended Boot Record, or EBR).


       These distinctions mean that primary and logical partitions  cannot  be
       arbitrarily  interspersed. A disk can contain one to three primary par-
       titions, a block of one or more logical partitions, and	one  to	 three
       more  primary  partitions (for a total of three primary partitions, not
       counting the extended partition). Primary partitions may not  be	 sand-
       wiched between logical partitions, since this would mean placing a pri-
       mary partition within an extended partition (which is just  a  specific
       type of primary partition).

       Unlike  most  disk utilities, fixparts' user interface ignores extended
       partitions. Internally, the program discards  the  information  on  the
       original	 extended partition and, when you tell it to save its changes,
       it generates a new extended partition to contain the then-defined logi-
       cal  partitions. This is done because most of the repairs and manipula-
       tions the tool performs require generating a fresh extended  partition,
       so keeping the original in the user interface would only be a complica-
       tion.

       Another unusual feature of fixparts' user interface is  that  partition
       numbers	do  not	 necessarily correlate with primary/logical status. In
       most  utilities,	 partitions  1-4  correspond  to  primary  partitions,
       whereas	partitions  5  and up are logical partitions. In fixparts, any
       partition number may be assigned primary or logical status, so long  as
       the  rules  for layout described earlier are obeyed. When the partition
       table is saved, partitions will	be  assigned  appropriately  and  then
       tools  such  as	the Linux kernel and fdisk will give them conventional
       numbers.

       When it first starts, fixparts performs a scan for  GPT	data.  If  the
       disk  looks  like  a conventional GPT disk, fixparts refuses to run. If
       the disk appears to be a conventional MBR disk but GPT  signatures  are
       present	in  the GPT primary or secondary header areas, fixparts offers
       to delete this extraneous data. If you tell it to do  so,  the  program
       immediately  wipes  the	GPT header or headers. (If only one header was
       found, only that one header will be erased, to  minimize	 the  risk  of
       damaging	 a  boot loader or other data that might have overwritten just
       one of the GPT headers.)

       With the exception of optionally erasing	 leftover  GPT	data  when  it
       first  starts,  fixparts	 keeps	all  changes  in memory until the user
       writes changes with the w command. Thus, you can adjust your partitions
       in the user interface and abort those changes by typing q to quit with-
       out saving changes.


OPTIONS
       The fixparts utility supports no command-line options, except for spec-
       ification of the target device.

       Most  interactions  with	 fixparts occur with its interactive text-mode
       menu. Specific functions are:


       a      Toggle the active/boot flag. This flag is required by some  boot
	      loaders and OSes.



       c      Recompute	 the  cylinder/head/sector (CHS) values for all parti-
	      tions. CHS addressing mode is largely obsolete,  but  some  OSes
	      and  utilities  complain if they don't like the CHS values. Note
	      that fixparts' CHS values are likely to be  incorrect  on	 disks
	      smaller than about 8 GiB except on Linux.


       l      Change  a	 partition's  status to logical. This option will only
	      work if the current partition layout  supports  such  a  change.
	      Note  that  if  changing a partition's status in this way is not
	      currently possible, making some other change may make it	possi-
	      ble. For instance, omitting a partition that precedes the target
	      partition may enable converting a partition to logical  form  if
	      there had been no free sectors between the two partitions.


       o      Omit  a partition. Once omitted, the partition will still appear
	      in the fixparts partition list, but it will be flagged as	 omit-
	      ted.  You can subsequently convert it to primary or logical form
	      with the r or l  commands,  respectively.	 When  you  save  your
	      changes with w, though, the partition will be lost.


       p      Display  basic partition summary data. This includes partition's
	      number, the boot/active flag's status, starting and ending  sec-
	      tor  numbers, primary/logical/omitted status, whether or not the
	      partition may be converted to logical form, and the  partition's
	      MBR types code.


       q      Quit  from  the  program	without saving your changes.  Use this
	      option if you just wanted to view information or if you  make  a
	      mistake and want to back out of all your changes.


       r      Change  a	 partition's  status to primary. This option will only
	      work if the current partition layout  supports  such  a  change.
	      Note  that  every	 partition  can theoretically become a primary
	      partition, although in some configurations, making  this	change
	      will  require  omitting some partitions.	If fixparts refuses to
	      allow changing a partition to primary, you may need  to  convert
	      other partitions to logical form or omit them entirely.


       s      Sort  partition  entries.	 This  option orders partitions in the
	      display to match their on-disk positions, which can make	under-
	      standing	the  disk layout easier in some cases. This option has
	      no effect on the ultimate ordering of logical partitions,	 which
	      are  sorted  before being saved. The order of primary partitions
	      in the final saved partition  table  may	be  affected  by  this
	      option.  In  both cases, as already noted, the partition numbers
	      displayed by fixparts may not be the same as those used  by  the
	      kernel or displayed by other partitioning tools.


       t      Change  a partition's type code. You enter the type code using a
	      one-byte hexadecimal number.


       w      Write data. Use this command to save your changes and exit  from
	      the program.


       ?      Print  the  menu.	 Type  this command (or any other unrecognized
	      command) to see a summary of available options.


BUGS
       As of March 2014 (version 0.8.10), fixparts should be  considered  beta
       software. Known bugs and limitations include:


       *      The program compiles correctly only on Linux, FreeBSD, Mac OS X,
	      and Windows.  Linux versions for x86-64 (64-bit), x86  (32-bit),
	      and  PowerPC  (32-bit) have been tested, with the x86-64 version
	      having seen the most testing. Under FreeBSD,  32-bit  (x86)  and
	      64-bit  (x86-64) versions have been tested. Only 32-bit versions
	      for Mac OS X and Windows have been tested.


       *      The FreeBSD version of the program can't write  changes  to  the
	      partition	 table to a disk when existing partitions on that disk
	      are mounted. (The same problem exists with  many	other  FreeBSD
	      utilities,  such	as gpt, fdisk, and dd.) This limitation can be
	      overcome by typing sysctl	 kern.geom.debugflags=16  at  a	 shell
	      prompt.


       *      The program can load only up to 128 partitions (4 primary parti-
	      tions and 124 logical partitions). This limit can be  raised  by
	      changing the #define MAX_MBR_PARTS line in the basicmbr.h source
	      code file and recompiling.


       *      The program can read partitions only if the disk has correct LBA
	      partition	 descriptors.  These  descriptors should be present on
	      any disk over 8 GiB in size or on smaller disks partitioned with
	      any but very ancient software.


       *      The  program makes no effort to preserve partition numbers. This
	      can have consequences for boot loaders and for mounting filesys-
	      tems  via	 /etc/fstab. It may be necessary to edit configuration
	      files or even to re-install your boot loader.


       *

	      The program may change the order of partitions in the  partition
	      table.


AUTHORS
       Primary author: Roderick W. Smith (rodsmith@rodsbooks.com)

       Contributors:

       * Yves Blusseau (1otnwmz02@sneakemail.com)

       * David Hubbard (david.c.hubbard@gmail.com)

       * Justin Maggard (justin.maggard@netgear.com)

       * Dwight Schauer (dschauer@ti.com)

       * Florian Zumbiehl (florz@florz.de)



SEE ALSO
       cfdisk  (8),  cgdisk  (8),  fdisk (8), mkfs (8), parted (8), sfdisk (8)
       gdisk (8) sgdisk (8)

       http://en.wikipedia.org/wiki/Master_boot_record

       http://www.rodsbooks.com/fixparts/


AVAILABILITY
       The fixparts command is part of the GPT fdisk package and is  available
       from Rod Smith.



Roderick W. Smith		    0.8.10			   FIXPARTS(8)
