DF(1) DF(1)
NAME
df - report filesystem disk space usage
SYNOPSIS
df[options][file...]
POSIX options: [-kP][--]
GNU options (shortest form): [-ahHiklmPv][-t fstype][-x fstype]
[--block-size=size][--print-type][--no-sync][--sync][--help]
[--version][--]
DESCRIPTION
df reports the amount of disk space used and available on filesystems.
With no arguments, df reports the space used and available on all cur-
rently mounted filesystems (of all types). Otherwise, df reports on
the filesystem containing each argument file.
POSIXDETAILS
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.
GNUDETAILS
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 filesys-
tem, df shows the space available on that filesystem rather than on the
filesystem containing the device node.
POSIXOPTIONS
-k Use 1024-byte units instead of the default 512-byte units.
-P Output in six columns, with heading 'Filesystem N-blocks Used
Available Capacity Mounted on' (with N=512, but N=1024 when the
-k option is given).
-- Terminate option list.
GNUOPTIONS
-a,--all
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 speci-
fied.
--block-size=size
Print sizes in blocks of size bytes. (New but broken in fileu-
tils-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 pow-
ers 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 fileu-
tils-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 ver-
sion.]
--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, espe-
cially 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.
GNUSTANDARDOPTIONS
--help Print a usage message on standard output and exit successfully.
--version
Print version information on standard output, then exit success-
fully.
-- Terminate option list.
ENVIRONMENT
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.
CONFORMINGTO
POSIX 1003.2
SEEALSO
mount(8)
NOTES
This page describes df as found in the fileutils-4.0 package; other
versions may differ slightly. Mail corrections and additions to
aeb
cwi.nl. Report bugs in the program to fileutils-
bugsgnu.edu.
GNU fileutils 4.0 1998-11 DF(1)
Take our 
