NAME
du — estimate file
space usage
SYNOPSIS
du |
[-a |
-s][-kx][-r][file
...] |
DESCRIPTION
By default, the du utility writes to
standard output the size of the file space allocated to, and the size of the
file space allocated to each subdirectory of, the file hierarchy rooted in
each of the specified files. The size of the file space allocated to a file
of type directory is defined as the sum total of space allocated to all
files in the file hierarchy rooted in the directory plus the space allocated
to the directory itself.
When du cannot stat()
files or stat() or read directories, it will report an
error condition and the final exit status will be affected. Files with
multiple links will be counted and written for only one entry. The directory
entry that is selected in the report is unspecified. By default, file sizes
are written in 512-byte units, rounded up to the next 512-byte unit.
OPTIONS
The du utility supports the XBD
specification,
Utility
Syntax Guidelines .
The following options are supported:
- -a
- In addition to the default output, report the size of each file not of
type directory in the file hierarchy rooted in the specified file.
Regardless of the presence of the
-aoption, non-directories given as file operands will always be listed. - -k
- Write the files sizes in units of 1024 bytes, rather than the default 512-byte units.
- -r
- Generate messages about directories that cannot be read, files that cannot be opened, and so on. This is the default case.
- -s
- Instead of the default output, report only the total sum for each of the specified files.
- -x
- When evaluating file sizes, evaluate only those files that have the same device as the file specified by the file operand.
OPERANDS
The following operand is supported:
- file
- The pathname of a file whose size is to be written. If no file is specified, the current directory is used.
STDIN
Not used.
INPUT FILES
None.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of
du :
LANG- Provide a default value for the internationalisation variables that are
unset or null. If
LANGis unset or null, the corresponding value from the implementation-dependent default locale will be used. If any of the internationalisation variables contains an invalid setting, the utility will behave as if none of the variables had been defined. LC_ALL- If set to a non-empty string value, override the values of all the other internationalisation variables.
LC_CTYPE- Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single- as opposed to multi-byte characters in arguments).
LC_MESSAGES- Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.
NLSPATH- Determine the location of message catalogues for the processing of LC_MESSAGES .
ASYNCHRONOUS EVENTS
Default.
STDOUT
The output from du consists of the amount
of the space allocated to a file and the name of the file, in the following
format:
"%d %s\n", <size>,
<pathname>
STDERR
Used only for diagnostic messages.
OUTPUT FILES
None.
EXTENDED DESCRIPTION
None.
EXIT STATUS
The following exit values are returned:
CONSEQUENCES OF ERRORS
Default.
APPLICATION USAGE
None.
EXAMPLES
None.
FUTURE DIRECTIONS
None.
SEE ALSO
ls(1) .