Using wildcard (*) we can print the individual size of each file and directories and then combine total size to print in the last line. The following example du command combine ( -c) the total disk size of specified ( -s) '/boot' and '/var' directory and print at the last line in human-readable format ( -h): # du -csh /boot/ /varĤ66M total Display individual size of all files and directories This is very useful when you like to combine the total size on multiple directories. To get the total size of a specified directory in a human-readable format which is very commonly used du command, use the following command: # du -sh /boot The -si option is like -h option but it uses powers of 1000 instead of 1024. In order to print the output in kilobyte (K), megabyte (M) and gigabyte (G) we have to use -h option. So far we see the disk size was showing in bytes that is not much human-readable format. You can print total disk usage from multiple directories as follows: # du -s /boot /var The following example, it shows the total size of '/boot' directory. To display the total size of a specified directory you have to use -s option but will not report subdirectories.

You can see that it prints the total size at the end of the command where '152440' is the total size (in bytes) of '/boot' directory. # du /bootĭu command with -a option prints the disk usage of all the files within the directory. If no file or directory name mentioned then du commad display disk usage of the current working directory.

By default, without any options, it displays the disk usage of the given file or directory and for each of the subdirectories in bytes.

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