An optional label can be specified to name the volume. The name must be between 1-27 characters and cannot contain a colon (:). By default, the volume will be named Untitled. default, the volume will be named Untitled.

If the destination medium is partitioned, one partition must be selected to receive the filesystem. If there is only one HFS partition on the medium, it will be selected by default. Otherwise, the desired partition number must be specified (as the ordinal nth HFS partition) on the command-line. The size of the partition determines the size of the resulting volume.

Partition number 0 can be specified to format the entire medium as a single filesystem without a partition map, erasing any existing partition information. Since this will destroy all the partitions, the -f option must be specified to force this operation if the medium currently contains a partition map.

If the medium is not partitioned (or if partition 0 is specified), the size or capacity of the medium determines the size of the resulting volume.

The new volume will be empty and will become "current" so subsequent commands will refer to it. The current working directory for the volume is set to the root of the volume.

% hformat /dev/fd0

If a floppy disk is available as /dev/fd0, this formats the disk as an HFS volume named Untitled. (N.B. The floppy the disk as an HFS volume named Untitled. (N.B. The floppy must already have received a low-level format by other means.)

% dd if=/dev/zero of=disk.hfs bs=1k count=800

% hformat -l "Test Disk" disk.hfs

This sequence creates an 800K HFS volume image in the file disk.hfs in the current directory, and names it Test Disk.

% hformat -l "Loma Prieta" /dev/sd2 1

If a SCSI disk is available as /dev/sd2, this initializes the first HFS partition on the disk (which must already exist) with a new filesystem, naming the resulting volume Loma Prieta.

% hformat -f /dev/sd2 0

This causes the medium accessible as /dev/sd2 to be reformatted as a single HFS volume, ignoring and erasing any existing partition information on the medium. The -f option must be specified if the medium is currently partitioned; otherwise the command will fail.

The smallest volume size which can be formatted with hformat is 800K.