Summarizes disk usage.
The du command displays the number of blocks used for files. If the File parameter specified is actually a directory, all files within the directory are reported on. If no File parameter is provided, the du command uses the files in the current directory.
If the File parameter is a directory, then the number of blocks reported is the sum of blocks allocated for the files in the directory and the blocks allocated for the directory itself.
If the object of the du command is a file or directory that exists inside a JFS2 snapshot, the du command gives information for the point-in-time object when the snapshot is created. This information does not include how much space is recovered if the snapshot itself is deleted.
Specifying the -a flag reports the number of blocks in individual files. Whether the -a flag is used or not, individual files specified by the File parameter are always listed.
Specifying the -s flag reports the total blocks for all specified files or all files in a directory.
Item | Description |
---|---|
-a | For each file specified, displays the disk usage of the file. For each directory specified, displays the disk usage of each individual file within the directory, including all subdirectories. Contrast this flag with the -s flag. |
-g | Calculates the block count in GB units rather than the default 512-byte units. The output values for the disk usage would be in floating point numbers as value of each unit in bytes is significantly high. |
-H | If a symbolic link is specified on the command line, the du command shall count the size of the file or file hierarchy referenced by the link. |
-k | Calculates the block count in 1024-byte units rather than the default 512-byte units. |
-l | Allocates blocks evenly among the links for files with multiple links. By default, a file with two or more links is counted only once. |
-L | If a symbolic link is specified on the command line or encountered during the traversal of a file hierarchy, the du command shall count the size of the file or file hierarchy referenced by the link. |
-m | Calculates the block count in MB units rather than the default 512-byte units. The output values for the disk usage would be in floating point numbers as value of each unit in bytes is significantly high. |
-r | Reports names of inaccessible files and directories. This is the default. |
-s | For each file specified, displays the disk usage of the file. For each directory specified, displays the total disk usage of all files within the directory, including all subdirectories. Contrast this flag with the -a flag. |
-x | When evaluating file sizes, evaluates only those files that reside on the same device as the file or directory specified by the File parameter. For example, you may specify a directory that contains files on several devices. In this case, the -x flag displays block sizes for all files that reside on the same device as the directory. |
This command returns the following exit values:
Item | Description |
---|---|
0 | Successful completion. |
>0 | An error occurred. |
du /home/fran
This displays
the number of disk blocks in the /home/fran directory
and each of its subdirectories.du -k /home/fran
This displays the number of 1024-byte disk blocks in the /home/fran directory and each of its subdirectories.du -m /home/fran
This displays the number of MB disk blocks rounded off to nearest
2nd decimal digit in the /home/fran directory and each of
its subdirectories.du -g /home/fran
This displays the number of GB disk blocks rounded off to nearest
2nd decimal digit in the /home/fran directory and each of
its subdirectories.du -a /home/fran
This displays the number of disk blocks contained in each file and
subdirectory of the /home/fran directory. 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.du -s /home/fran
The -s flag instructs
the du command to display only the sum total disk usage of
the /home/fran directory and the files it contains. By default,
the du command displays an error message if it cannot read
a file or directory.du -L /home/fran
du -H mylink
Item | Description |
---|---|
/usr/bin/du | Contains the du command. |