The option --backup force sfdisk to store *all* fragments of the
partition table (including MBR partition tables store in the
extended partitions) to
$HOME/sfdisk-<devname>-<offset>.bak
The options -O, -backup-file <path> allows to override the default
path, but sfdisk still appends <devname>-<offset>.bak to the <path>.
The backup files always contain only raw data from the device, so it's
possible to use dd(1) to restore original data on the device.
The original sfdisk also supported -O <file>, but semantic was little
bit different:
- all was based on 512-byte sectors
- all sectors was stored to the one file in format
<offset>|<sector>|<offset>|...
this original concept makes the backup files specific to sfdisk and with
dependence on sector size.
The new concept is the same we already use for wipefs(8) backup files.
Example (disk with GPT):
# sfdisk /dev/sda --backup
Welcome to sfdisk (util-linux 2.25.202-f4deb-dirty).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Backup files:
PMBR (offset 0, size 512): /root/sfdisk-sda-0x00000000.bak
GPT Header (offset 512, size 512): /root/sfdisk-sda-0x00000200.bak
GPT Entries (offset 1024, size 16384): /root/sfdisk-sda-0x00000400.bak
Signed-off-by: Karel Zak <kzak@redhat.com>
The sfdisk does not care about compatibility with classic DOS
partitioning, and it does not warn about incompatibility with DOS at
all. It means that --Linux is default and it's unnecessary to use
this option.
It's the same situation like with "--unit S", these options are very
probably often used in scripts, and these all is default now. So for
backward compatibility new sfdisk accepts these options on command
line, but prints "option is deprecated" warning message.
Signed-off-by: Karel Zak <kzak@redhat.com>
Note that original sfdisk implementation suppressed warning
messages for --quiet.
Now we keep warning and error messages visible, but suppress
extra info messages only (for example to make it more usable in
scripts). IMHO suppress warnings is bad idea.
Signed-off-by: Karel Zak <kzak@redhat.com>
The patch also makes --{id,change-id,print-id} deprecated in favour
of --parttype. The original --id is too generic option name and the
--print-id and --change-id are unnecessary and inconsistent with
another sfdisk options (e.g. we don't have --change-bootable)
Signed-off-by: Karel Zak <kzak@redhat.com>
Sfdisk prints out a warning about extended partition not
starting at a cylinder boundary. Since this is irrelevant
for linux, the -L option should suppress this warning.
Signed-off-by: Petr Uzel <petr.uzel@suse.cz>