NAME
df
—
display free disk space
SYNOPSIS
df |
[-hiklnP ] [-t
type] [[file |
file_system] ...] |
DESCRIPTION
The df
utility displays statistics about
the amount of free disk space on the specified
file_system or on the file system of which
file is a part. By default, values are displayed as
512-byte block counts. If neither a file nor a
file_system operand is specified, statistics for all
mounted file systems are displayed (subject to the
-l
and -t
options
below).
The options are as follows:
-h
- "Human-readable" output. Use unit suffixes: Byte, Kilobyte,
Megabyte, Gigabyte, Terabyte, Petabyte, Exabyte in order to reduce the
number of digits to four or less. This option is incompatible with the
-P
option. -i
- Include statistics on the number of free inodes. This option is
incompatible with the
-P
option. -k
- By default, all sizes are reported in 512-byte block counts. The
-k
option causes the numbers to be reported in kilobyte counts. -l
- Display statistics only about mounted file systems with the
MNT_LOCAL
flag set. If a non-local file system is given as an argument, a warning is issued and no information is given on that file system. -n
- Print out the previously obtained statistics from the file systems. This
option should be used if it is possible that one or more file systems are
in a state such that they will not be able to provide statistics without a
long delay. When this option is specified,
df
will not request new statistics from the file systems, but will respond with the possibly stale statistics that were previously obtained. -P
- Print out information in a stricter format designed to be parsed by portable scripts.
-t
type- Indicate the actions should only be taken on file systems of the specified type. More than one type may be specified in a comma-separated list. The list of file system types can be prefixed with “no” to specify the file system types for which action should not be taken. If a file system is given on the command line that is not of the specified type, a warning is issued and no information is given on that file system.
It is not an error to specify more than one of the mutually
exclusive options -h
and -k
.
Where more than one of these options is specified, the last option given
overrides the others.
ENVIRONMENT
BLOCKSIZE
- If the environment variable
BLOCKSIZE
is set, and the-h
or-k
options are not specified, the block counts will be displayed in units of that size block.
EXIT STATUS
The df
utility exits 0 on success,
and >0 if an error occurs.
EXAMPLES
Output, in a strict format suitable for portable scripts, disk space statistics for the /usr file system using kilobyte block sizes:
$ df -kP /usr
SEE ALSO
quota(1), getfsstat(2), statfs(2), getmntinfo(3), fstab(5), mount(8), quot(8)
STANDARDS
The df
utility is compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
specification.
The flags [-hiln
] are extensions to that
specification.
Behaviour for the -t
flag differs between
this implementation and IEEE Std 1003.1-2008
(“POSIX.1”).
HISTORY
A df
utility appeared in
Version 3 AT&T UNIX.