df reports the amount of disk space used and available on
filesystems.
With no arguments,
df reports the space used and available on all
currently mounted filesystems (of all types).
Otherwise,
df reports on the filesystem containing each argument
file.
The output is in 512-byte units by default, but in
1024-byte units when the -k option is given.
The output format is undefined, unless the -P option is given.
If
file is not a regular file, a directory or a FIFO, the result
is unspecified.
The output is in 1024-byte units (when no units are
specified by options), unless the environment variable
POSIXLY_CORRECT is set, in which case POSIX is followed.
If an argument
file is a disk device file containing a mounted filesystem,
df shows the space available on that filesystem rather
than on the filesystem containing the device node.
Include in the listing filesystems that have a size of 0 blocks,
which are omitted by default. Such filesystems are typically
special-purpose pseudo-filesystems, such as automounter entries.
Also, filesystems of type "ignore" or "auto", supported by some
operating systems, are only included if this option is specified.
--block-size=size
Print sizes in blocks of
size bytes. (New but broken in fileutils-4.0.)
-h, --human-readable
Append a size letter such as
M for binary megabytes (‘mebibytes’) to each size.
-H, --si
Do the same as for
-h, but use the official SI units (with powers of 1000 instead of 1024,
so that M stands for 1000000 instead of 1048576).
(New in fileutils-4.0.)
-i, --inodes
List inode usage information instead of block usage. An inode
(short for index node) contains information about a file such
as its owner, permissions, timestamps, and location on the disk.
-k, --kilobytes
Print sizes in 1024-byte blocks.
-l, --local
Limit the output to local filesystems only.
(New in fileutils-4.0.)
-m, --megabytes
Print sizes in binary megabyte (that’s 1048576 bytes) blocks.
Note that the four options -h, -H, -k, -m are mutually exclusive
and only the last one is effective; for example, it is not the case
that giving both the --si and -m options would result in output
in (actual, 1000000-byte) megabytes. [The interpretation of blocksizes
is also influenced by the environment variable BLOCK_SIZE, but this
does not work in the fileutils-4.0 version.]
--no-sync
Do not invoke the
sync system call before getting any usage data.
This may make
df run significantly faster, but on some systems (notably SunOS)
the results may be slightly out of date. This is the default.
-P, --portability
Use the
POSIX output format. This is like the default format
except that the information about each filesystem is always
printed on exactly one line; a mount device is never put on a line
by itself. This means that if the mount device name is more than
20 characters long (e.g., for some network mounts), the columns
are misaligned.
--sync
Invoke the
sync system call before getting any usage data. On some systems
(notably SunOS), doing this yields more up to date results,
but in general this option makes
df much slower, especially when there are many or very busy filesystems.
-t fstype, --type=fstype
Limit the listing to filesystems of type
fstype. Multiple filesystem types can be specified by giving multiple
-t options. By default, nothing is omitted.
-T, --print-type
Print each filesystem’s type.
The types given are those reported by the system
(and are found in a system-dependent way, for example by reading
/etc/mtab). See also
mount(8).
-x fstype, --exclude-type=fstype
Limit the listing to filesystems not of type
fstype. Multiple filesystem types can be eliminated by giving multiple
-x options. By default, no filesystem types are omitted.
-v
Ignored; for compatibility with System V versions of
df.
The variable POSIXLY_CORRECT determines the choice of unit.
If it is not set, and the variable BLOCKSIZE has a value starting
with ‘HUMAN’, then behaviour is as for the -h option,
unless overridden by -k or -m options.
The variables LANG, LC_ALL, LC_CTYPE and LC_MESSAGES have the
usual meaning.
