disklabel(8)                 System Manager's Manual                disklabel(8)

     disklabel – manipulate and query an Apple Label disk label

     disklabel -create disk-device [-msize=size] [property=value] [...]
     disklabel -status disk-device
     disklabel -properties disk-device [property[=value]] [...]
     disklabel -destroy disk-device

     The disklabel utility manipulates ``Apple Label'' partition metadata.
     ``Apple Label'' partitions allow for a disk device to have a consistent
     name, ownership, and permissions across reboots, even though uses a dynamic
     pseudofilesystem for /dev.

     The ``Apple Label'' partition uses a set of metadata (as a plist) in a
     reserved area of the partition.  This metadata describes the owner, name,
     and so forth.

     When -create is used, the -msize argument can specify the size of metadata
     area; the default is 128Kbytes.  The default size unit is bytes, but the
     following suffixes may be used to multiply by the given factor: ``b''
     (512), ``k'' (1024), ``m'' (1048576), and ``g'' (1073741824).

     Although any key-value pair can be specified for the properties, certain
     keys are used by the system:

     owner-uid   The user (as either a string or numeric value) to own the

     owner-gid   The group (as either a string or numeric value) associated with
                 the device.

     owner-mode  The permissions (as a numeric value) for the device.

     dev-name    The name for the device.

     If the owner-uid and owner-gid properties are given as strings, the
     disklabel utility will attempt to look up the names (as users or groups, as
     appropriate), and will store the numeric values in the metadata.  If it
     cannot find the names, and the values are not given as numbers, it will
     print an error, and not store the key/value pairs in the metadata.

     The owner-mode property may be given in decimal, or in octal by using a
     preceding ``0'' (e.g., ``0666'').

     Any property may be forced to be treated as a string by enclosing it in
     double-quotation marks; bear in mind that shell escapes will probably be
     necessary in this sitation.

     The -properties directive can print out all keys (if no arguments are
     given), a requested set of keys (if a list of key names is given), or can
     modify (or add) keys (if a key-value pairs are given).

     disklabel also maintains a checksum of the metadata; the -status directive
     verifies this checksum.

     The following example will create a device with 1MByte of metadata area,
     owned by fred, with a device name of fred, and be writable by fred:

           disklabel -create /dev/rdisk1s1 -msize=1M owner-uid=fred
           dev-name=fred owner-mode=0644

     The following example will then print out the key-value pairs from the
           disklabel -properties /dev/rdisk1s1


macOS 12.1                      September 3, 2004                     macOS 12.1