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fdisk(1M)

create (recover) a complete disk archive

From the original Amiga UNIX 2.1 manual. Some things it mentions may not be in this release.

NAME

fdisk - create (recover) a complete disk archive

SYNOPSIS

fdisk -B [-dovAENV] bkjobid odname opartdev odlab descript

fdisk -RC [-dovAENV] odname opartdev descript rsjobid

DESCRIPTION

The fdisk command is invoked as a child process by other shell commands. The command name, fdisk, is read either from the bkhist.tab or the bkreg -m command and option. The -B, -R, and -C options are passed to fdisk by the shell commands backup and restore. The other options are passed from the bkhist.tab file or the bkreg -p command and option. The arguments are sent to fdisk from various locations in the backup service.

fdisk -B is invoked as a child process by backup to record the formatting information required to recreate the entire disk as it existed at the time of the archiving operation. The formatting information consists of the disk's volume name (not to be confused with the volume name associated with each filesystem partition on the disk), the partitions sizes and locations, and volume names. The resulting backup is a data file, including the results of a prtvtoc command that provides the information required to recreate the disk. The backup is recorded in the backup history log, /etc/bkup/bkhist.tab.

fdisk -RC is invoked as a child process by rsoper to reconstruct a disk using the formatting information previously archived, and to issue the appropriate restore requests to repopulate the most recent data on the disk. The archive is assumed to have been created by fdisk -B. It contains data describing the format of the disk and the names of the filesystems and data partitions that were present on it at the time of the archiving operation. The arguments to fdp are defined as follows:

bkjobid

the job id assigned by backup. The method uses the bkjobid when it creates history log entries.

odname the name of the data partition that is to  be  backed
       up.   Unused  by  fdisk,  but  supplied by backup for
       command-line  compatibility  with   other   archiving
       methods.

opartdev

the name of the raw (character) device (partition of the disk) that represents the entire disk

odlab the volume name on the filesystem [see labelit(1M)]. Unused by fdisk, but supplied by backup for commandline compatibility with other archiving methods.

descript

is a description for a destination device in the form:

            dgroup:dname:dchar:dlabels
       dgroup    specifies    a    device     group     [see
       devgroup.tab(4)].
       dname  specifies  a  particular  device   name   [see
       device.tab(4)].
       dchars specifies characteristics associated with  the
       device.   If  specified, dchar overrides the defaults
       for   the   specified   device   and   group.    (See
       device.tab(4)  for  a  further  description of device
       characteristics).
       dlabels specifies the volume names for the  media  to
       be used for reading or writing the archive.

rsjobid

the job id assigned by restore.

Options

Some options are only significant during fdisk -B invocations; they are accepted but ignored during fdisk -R invocations because the command is invoked and options are specified automatically by restore. These options are flagged with an asterisk (*).

d* Inhibits recording the archive in the backup history log.

o Permits the user to override media insertion requests [see getvol(1M) and the description of the -o option].

v* Validates the archive as it is written. A checksum is computed as the archive is being written; as each medium is completed, it is re-read and the checksum recomputed to verify that each block is readable and correct. If either check fails, the medium is considered unreadable. If -A has been specified, the archiving operation fails; otherwise, the operator is prompted to replace the failed medium.

A Establishes automated mode, (i.e., does not prompt the user to insert or remove media).

E* Reports an estimate of media usage for the archive; then performs the backup.

N* Reports an estimate of media usage for the archive; does not perform the backup.

V* Generates the name and type of each partition on the disk as its formatting information is read-to or written-from the destination device.

User Interactions

The connection between an archiving method and backup is more complex than a simple fork/exec or pipe. backup is responsible for all interactions with the user, either directly, or through bkoper. Therefore, fdisk neither reads from standard-input nor writes to standard-output or standard-error. A method library must be used [see libbrmeth(3)] to communicate reports (estimates, filenames, periods, status, etc.) to backup.

DIAGNOSTICS

The exit codes for fdisk are the following:

0 = successful completion of the task
1 = one or more parameters to fdisk are invalid.
2 = an error has occurred which caused fdisk to fail to
      complete all portions of its task.

FILES