du Command in Linux
The Linux du command displays the estimated disk usage of a file or directory. It is a powerful command line utility that monitors disk usage in Linux.
The du command is one of the standard utilities that can be combined with other utilities for customized output. It can also easily be incorporated with shell scripting.
Table of Contents
Here is a comprehensive guide to the options available with the du command −
Syntax of du Command
The syntax of the Linux du command is as follows −
du [options] [file / directory]
To get the desired output various options can be specified in the [options] field. The disk usage of the file and directory path can be mentioned in the [file / directory] field.
du Command Options
The options used with the du command are listed below −
| Flags | Options | Description |
|---|---|---|
| -0 | --null | It ends the output with NULL, not newline |
| -a | --all | It prints the disk usage of all files and directories including the hidden ones |
| --apparent-size | It displays the apparent size (It might differ from the disk usage due to sparse files) | |
| -B size | --block-size= size | It scales the output by the mentioned size (size can be K, M, or G) |
| -b | --bytes | It is equivalent to --block-size=1 or --apparent-size |
| -c | --total | It displays the total of the specified file, directory, and files within it |
| -D | --difference-args | It displays the disk usage of the target file or directory of a symbolic link |
| -d N | --max-depth= N | It displays the disk usage of a directory till the specified depth of the directory |
| --file0-from= F | It displays the disk usage of null-terminated file | |
| -H | It is equivalent to -D and --difference-args options | |
| -h | --human-readable | It displays the disk usage in human-readable form (25K, 100M, 2G) |
| --inode | It displays the disk usage of inodes instead of blocks | |
| -k | It is equivalent to --block-size=1K | |
| -L | --difference | It displays the disk usage of the targe files and directories of symbolic links |
| -l | --count-links | It displays the size of both the original file and directory and the hard link |
| -m | It is equivalent to --block-size=1M | |
| -P | --no-difference | It does not follow the symbolic link (default) |
| -S | --separate-dirs | It skips the disk usage of the subdirectories |
| --si | It is equivalent to -h with a base of 1000 instead of 1024 | |
| -s | --summarize | It displays the total size of each specified argument |
| -t size | --threshold= size | It excludes the entries by the specified size |
| --time | It displays the last modification time of the specified file, directories, and subdirectories | |
| --time= word | It displays the time by the specified word such as atime or ctime | |
| --time-style= style | It displays the time by the specified format such as full-iso, long-iso, or +FORMAT | |
| -X file | --exclude-from= file | It excludes the specified file |
| --exclude= pattern | It excludes files of the specified pattern | |
| -x | --one-file-system | It excludes directories on a different file system |
| --help | It displays the help of the du command | |
| --version | It displays the version of the command |
Examples of du Command in Linux
This section demonstrates the usage of the du command in Linux with examples −
- Displaying the Disk Usage of a File
- Displaying the Disk Usage of a Directory
- Displaying Disk Usage in Human-Readable Form
- Displaying Disk Usage in the Specified Block Size
- Displaying Disk Usage of All Files and Documents
- Getting Disk Usage with Null
- Displaying the Disk Usage Total of All the Output Entries
- Displaying Disk Usage with Last Modification Time
- Displaying Disk Usage Excluding Specific Files
Displaying the Disk Usage of a File
To display the disk usage of a file, use the du command and specify the file name −
du file.txt
To display the disk usage of a file through a path, use −
du Documents/Files/file.txt
Displaying the Disk Usage of a Directory
To display the disk usage of a directory, use the directory name or path −
du directory
Displaying Disk Usage in Human-Readable Form
To display the disk usage in human-readable form, use the -h or --human-readable options −
du -h Documents/Files/file.txt
It shows the disk usage with units such as K, M, or G.
Displaying Disk Usage in the Specified Block Size
To display the disk usage in a specific block size, use the -B or --block-size option −
du -B M directory
Displaying Disk Usage of All Files and Documents
To display disk usage of all the files and directories in the specified path, use the -a or --all option −
du -ah directory
The -h flag displays the disk usage in human-readable form.
Getting Disk Usage with Null
To get du command output with Null instead of newline, use the -0 or --null option. Some applications require null to process the data.
du -0 file.txt
Displaying the Disk Usage Total of All the Output Entries
To display the total disk usage of all the output entries, use the -c option or --total.
du -c directory/
It displays a separate entry at the end of the output.
Displaying Disk Usage with Last Modification Time
To display the last modification time of the specified file with the du command, use the --time option −
du --time file.txt
To get the last access and creation time, use the atime or ctime with the --time option. For example, to display the last access time of a file, use −
du --time=atime file.txt
To change the time format, use the --time-style option −
du --time=atime --time-style=+%m-%d-%Y file.txt
Displaying Disk Usage Excluding Specific Files
To print the disk usage with the du command to exclude a file with a pattern, use the --exclude option with the pattern. For example, to exclude the HTML file, use −
du -a --exclude="*.html" directory
To exclude files of a specific size, the -t or --threshold option is used. For example, to exclude files of 50KB or less, use
du -t 170K directory
Displaying Disk Usage by Directory Depth
To display the disk usage by the directory level, -d or --max-depth options are used. For example, to display the disk usage of the parent directory and its first level of subdirectories, the maximum depth will be 1.
du -d 1 directory
Now, lets display the disk usage of the parent directory, its first level of subdirectories, and its subdirectories.
du -d 2 directory
Conclusion
The du command in Linux displays the estimated disk usage of a file or directory. The output can be customized using various options such as filter by file, wild card, or size. Moreover, controlling directory depth, and easy integration with commands make this command a handy tool for system administrators.
In this tutorial, we explained the du command, its syntax, options, and usage through various examples.