du - Displays a summary of disk usage
du [-a | -s] [-klrx] [directory...]
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-a Displays disk use for each file. Without -a, du does not report on
files unless directory explicitly names a file.
[Tru64 UNIX] When run on an AdvFS clone fileset, du -a displays the
disk use for each file in the original fileset at the time the clone
fileset was created.
-s Displays only the grand total for each of the specified directories, or
for a file if used with -a.
-k Displays block count in kilobytes (1024 bytes) instead of multiples of
-l [Tru64 UNIX] Allocates blocks, in files with multiple links, evenly
among the links. By default, a file with two or more links is counted
-r Displays an error message when du encounters an inaccessible directory,
or an inaccessible file when used with -a.
-x Displays information about only the specified file system. For exam-
ple, if you want to display information about only the root file sys-
tem, specify both the -x option and the root file system (/).
The pathname of a directory to be examined. All subdirectories of
directory are examined.
If directory evaluates to a file name, then only information about the
file is provided.
The du command gives the number of blocks in all directories (listed recur-
sively) within each specified directory.
[Tru64 UNIX] When the -a option is specified, du reports the number of
blocks in individual files. The block count includes the indirect blocks
of each file and is in 512-byte units, independent of the cluster size used
by the system. If no file or directory name is provided, the du command
uses the current directory.
The du utility is marked LEGACY in XCU Issue 5.
If too many files are distinctly linked, du counts the excess files more
The following exit values are returned:
0 Successful completion.
>>0 An error occurred.
1. To display the disk usage of a directory tree and each of its sub-
The previous command displays the number of disk blocks in the /u/fran
directory and each of its subdirectories.
2. To display the disk usage of each file, enter:
du -a /u/fran
The previous command displays the number of disk blocks contained in
each file and subdirectory of /u/fran. The number beside a directory
is the disk usage of that directory tree. The number beside a regular
file is the disk usage of that file alone.
3. To display only the total disk usage of a directory tree, enter:
du -rs /u/fran
The previous command displays only the sum total disk usage of /u/fran
and the files it contains (-s). The -r option tells du to display an
error message if it cannot read a file or directory.
4. To restrict the disk usage information to the root (/) file system,
du -x /
The previous command displays information only about the root file
system and does not display information about the file systems located
under the root file system.
The following environment variables affect the execution of du:
Provides a default value for the internationalization variables that
are unset or null. If LANG is unset or null, the corresponding value
from the default locale is used. If any of the internationalization
variables contain an invalid setting, the utility behaves as if none of
the variables had been defined.
If set to a non-empty string value, overrides the values of all the
other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi-
byte characters in arguments).
Determines the locale for the format and contents of diagnostic mes-
sages written to standard error.
Determines the location of message catalogues for the processing of
Commands: df(1), ls(1), quot(8)
Functions: lseek(2), stat(2)