df displays the amount of disk space occupied by ufs file systems, the amount of used and available space, and how much of the file system's total capacity has been used.The amount of space reported as used and available is less than the amount of space in the file system; this is because the system reserves a fraction of the space in the file system to allow its file system allocation routines to work well. The amount reserved is typically about 10%; this may be adjusted using tunefs(1M). When all the space on the file system except for this reserve is in use, only the superuser can allocate new files and data blocks to existing files. When the file system is overallocated in this way, df may report that the file system is more than 100% utilized.If neither directory nor special is specified, df displays information for all mounted ufs file systems.

The following options are supported:

generic_options

Options supported by the generic df command. See df(1M) for a description of these options.

-o

Specify ufs file system specific options. The available option is:

i

Report the number of used and free inodes. This option may not be used with generic_options.

/etc/mnttab

list of file systems currently mounted

See attributes(5) for descriptions of the following attributes:

df(1M), tunefs(1M), fs_ufs(4), mnttab(4), attributes(5)

df calculates its results differently for mounted and unmounted file systems. For unmounted systems, the numbers reflect the 10% reservation mentioned above; this reservation is not reflected in df output for mounted file systems. For this reason, the available space reported by the generic command may differ from the available space reported by this module.