File: coreutils.info, Node: du invocation, Next: stat invocation, Prev: df invocation, Up: Disk usage
14.2 'du': Estimate file space usage
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'du' reports the amount of disk space used by the specified files and
for each subdirectory (of directory arguments). Synopsis:
du [OPTION]... [FILE]...
With no arguments, 'du' reports the disk space for the current
directory. Normally the disk space is printed in units of 1024 bytes,
but this can be overridden (*note Block size::). Non-integer quantities
are rounded up to the next higher unit.
If two or more hard links point to the same file, only one of the
hard links is counted. The FILE argument order affects which links are
counted, and changing the argument order may change the numbers that
'du' outputs.
The program accepts the following options. Also see *note Common
options::.
'-0'
'--null'
Output a zero byte (ASCII NUL) at the end of each line, rather than
a newline. This option enables other programs to parse the output
of 'du' even when that output would contain data with embedded
newlines.
'-a'
'--all'
Show counts for all files, not just directories.
'--apparent-size'
Print apparent sizes, rather than disk usage. The apparent size of
a file is the number of bytes reported by 'wc -c' on regular files,
or more generally, 'ls -l --block-size=1' or 'stat --format=%s'.
For example, a file containing the word 'zoo' with no newline
would, of course, have an apparent size of 3. Such a small file
may require anywhere from 0 to 16 KiB or more of disk space,
depending on the type and configuration of the file system on which
the file resides. However, a sparse file created with this
command:
dd bs=1 seek=2GiB if=/dev/null of=big
has an apparent size of 2 GiB, yet on most modern systems, it
actually uses almost no disk space.
'-B SIZE'
'--block-size=SIZE'
Scale sizes by SIZE before printing them (*note Block size::). For
example, '-BG' prints sizes in units of 1,073,741,824 bytes.
'-b'
'--bytes'
Equivalent to '--apparent-size --block-size=1'.
'-c'
'--total'
Print a grand total of all arguments after all arguments have been
processed. This can be used to find out the total disk usage of a
given set of files or directories.
'-D'
'--dereference-args'
Dereference symbolic links that are command line arguments. Does
not affect other symbolic links. This is helpful for finding out
the disk usage of directories, such as '/usr/tmp', which are often
symbolic links.
'-d DEPTH'
'--max-depth=DEPTH'
Show the total for each directory (and file if -all) that is at
most MAX_DEPTH levels down from the root of the hierarchy. The
root is at level 0, so 'du --max-depth=0' is equivalent to 'du -s'.
'--files0-from=FILE'
Disallow processing files named on the command line, and instead
process those named in file FILE; each name being terminated by a
zero byte (ASCII NUL). This is useful when the list of file names
is so long that it may exceed a command line length limitation. In
such cases, running 'du' via 'xargs' is undesirable because it
splits the list into pieces and makes 'du' print with the '--total'
('-c') option for each sublist rather than for the entire list.
One way to produce a list of ASCII NUL terminated file names is
with GNU 'find', using its '-print0' predicate. If FILE is '-'
then the ASCII NUL terminated file names are read from standard
input.
'-H'
Equivalent to '--dereference-args' ('-D').
'-h'
'--human-readable'
Append a size letter to each size, such as 'M' for mebibytes.
Powers of 1024 are used, not 1000; 'M' stands for 1,048,576 bytes.
This option is equivalent to '--block-size=human-readable'. Use
the '--si' option if you prefer powers of 1000.
'--inodes'
List inode usage information instead of block usage. This option
is useful for finding directories which contain many files, and
therefore eat up most of the inodes space of a file system (see
'df', option '--inodes'). It can well be combined with the options
'-a', '-c', '-h', '-l', '-s', '-S', '-t' and '-x'; however, passing
other options regarding the block size, for example '-b', '-m' and
'--apparent-size', is ignored.
'-k'
Print sizes in 1024-byte blocks, overriding the default block size
(*note Block size::). This option is equivalent to
'--block-size=1K'.
'-L'
'--dereference'
Dereference symbolic links (show the disk space used by the file or
directory that the link points to instead of the space used by the
link).
'-l'
'--count-links'
Count the size of all files, even if they have appeared already (as
a hard link).
'-m'
Print sizes in 1,048,576-byte blocks, overriding the default block
size (*note Block size::). This option is equivalent to
'--block-size=1M'.
'-P'
'--no-dereference'
For each symbolic links encountered by 'du', consider the disk
space used by the symbolic link.
'-S'
'--separate-dirs'
Normally, in the output of 'du' (when not using '--summarize'), the
size listed next to a directory name, D, represents the sum of
sizes of all entries beneath D as well as the size of D itself.
With '--separate-dirs', the size reported for a directory name, D,
will exclude the size of any subdirectories.
'--si'
Append an SI-style abbreviation to each size, such as 'M' for
megabytes. Powers of 1000 are used, not 1024; 'M' stands for
1,000,000 bytes. This option is equivalent to '--block-size=si'.
Use the '-h' or '--human-readable' option if you prefer powers of
1024.
'-s'
'--summarize'
Display only a total for each argument.
'-t SIZE'
'--threshold=SIZE'
Exclude entries based on a given SIZE. The SIZE refers to used
blocks in normal mode (*note Block size::), or inodes count in
conjunction with the '--inodes' option.
If SIZE is positive, then 'du' will only print entries with a size
greater than or equal to that.
If SIZE is negative, then 'du' will only print entries with a size
smaller than or equal to that.
Although GNU 'find' can be used to find files of a certain size,
'du''s '--threshold' option can be used to also filter directories
based on a given size.
Please note that the '--threshold' option can be combined with the
'--apparent-size' option, and in this case would elide entries
based on its apparent size.
Please note that the '--threshold' option can be combined with the
'--inodes' option, and in this case would elide entries based on
its inodes count.
Here's how you would use '--threshold' to find directories with a
size greater than or equal to 200 megabytes:
du --threshold=200MB
Here's how you would use '--threshold' to find directories and
files - note the '-a' - with an apparent size smaller than or equal
to 500 bytes:
du -a -t -500 --apparent-size
Here's how you would use '--threshold' to find directories on the
root file system with more than 20000 inodes used in the directory
tree below:
du --inodes -x --threshold=20000 /
'--time'
Show time of the most recent modification of any file in the
directory, or any of its subdirectories.
'--time=ctime'
'--time=status'
'--time=use'
Show the most recent status change time (the 'ctime' in the inode)
of any file in the directory, instead of the modification time.
'--time=atime'
'--time=access'
Show the most recent access time (the 'atime' in the inode) of any
file in the directory, instead of the modification time.
'--time-style=STYLE'
List timestamps in style STYLE. This option has an effect only if
the '--time' option is also specified. The STYLE should be one of
the following:
'+FORMAT'
List timestamps using FORMAT, where FORMAT is interpreted like
the format argument of 'date' (*note date invocation::). For
example, '--time-style="+%Y-%m-%d %H:%M:%S"' causes 'du' to
list timestamps like '2002-03-30 23:45:56'. As with 'date',
FORMAT's interpretation is affected by the 'LC_TIME' locale
category.
'full-iso'
List timestamps in full using ISO 8601 date, time, and time
zone format with nanosecond precision, e.g., '2002-03-30
23:45:56.477817180 -0700'. This style is equivalent to
'+%Y-%m-%d %H:%M:%S.%N %z'.
'long-iso'
List ISO 8601 date and time in minutes, e.g., '2002-03-30
23:45'. These timestamps are shorter than 'full-iso'
timestamps, and are usually good enough for everyday work.
This style is equivalent to '+%Y-%m-%d %H:%M'.
'iso'
List ISO 8601 dates for timestamps, e.g., '2002-03-30'. This
style is equivalent to '+%Y-%m-%d'.
You can specify the default value of the '--time-style' option with
the environment variable 'TIME_STYLE'; if 'TIME_STYLE' is not set
the default style is 'long-iso'. For compatibility with 'ls', if
'TIME_STYLE' begins with '+' and contains a newline, the newline
and any later characters are ignored; if 'TIME_STYLE' begins with
'posix-' the 'posix-' is ignored; and if 'TIME_STYLE' is 'locale'
it is ignored.
'-X FILE'
'--exclude-from=FILE'
Like '--exclude', except take the patterns to exclude from FILE,
one per line. If FILE is '-', take the patterns from standard
input.
'--exclude=PATTERN'
When recursing, skip subdirectories or files matching PATTERN. For
example, 'du --exclude='*.o'' excludes files whose names end in
'.o'.
'-x'
'--one-file-system'
Skip directories that are on different file systems from the one
that the argument being processed is on.
On BSD systems, 'du' reports sizes that are half the correct values
for files that are NFS-mounted from HP-UX systems. On HP-UX systems, it
reports sizes that are twice the correct values for files that are
NFS-mounted from BSD systems. This is due to a flaw in HP-UX; it also
affects the HP-UX 'du' program.
An exit status of zero indicates success, and a nonzero value
indicates failure.