ls Command in Linux With Example
ls
is one of the basic commands that any Linux user should know.
The ls
command lists files and directories within the file system, and shows detailed information about them. It is a part of the GNU core utilities package which is installed on all Linux distributions.
This article will show you how to use the ls command through practical examples and detailed explanations of the most common ls options.
How to Use the ls
Command
The syntax for the ls
command is as follows:
$ ls [OPTIONS] [FILES]
When used with no options and arguments, ls
displays a list of the names of all files in the current working directory :
$ ls
The files are listed in alphabetical order in as many columns as can fit across your terminal:
OUTPUT
cache db empty games lib local lock log mail opt run spool tmp
To list files in a specific directory, pass the directory path as an argument to the ls
command. For example, to list the contents of the /etc
directory, you would type:
$ ls /etc
You can also pass multiple directories and files separated by space:
$ ls /etc /var /etc/passwd
If the user you are logged in with doesn’t have read permissions to the directory, you will get a message saying that ls
can’t open the directory:
$ ls /root
OUTPUT
ls: cannot open directory '/root': Permission denied
The ls
command has a number of options. In the sections below, we will explore the most commonly used options.
Long Listing Format
The default output of the ls
command shows only the names of the files and directories, which is not very informative.
The -l
( lowercase L) option tells ls
to print files in a long listing format.
- The file type.
- The file permissions.
- Number of hard links to the file.
- File owner.
- File group.
- File size.
- Date and Time.
- File name.
Here is an example:
$ ls -l /etc/hosts
OUTPUT
-rw-r--r-- 1 root root 337 Oct 4 11:31 /etc/hosts
Let’s explain the most important columns of the output.
The first character shows the file type. In this example, the first character is -
, which indicates a regular file. Values for other file types are as follows:
-
– Regular file.b
– Block special file.c
– Character special file.d
– Directory.l
– Symbolic link.n
– Network file.p
– FIFO.s
– Socket.
The next nine characters are showing the file permissions. The first three characters are for the user, the next three are for the group, and the last three are for others. You can change the file permissions with the chmod
command. The permission character can take the following value:
r
– Permission to read the file.w
– Permission to write to the file.x
– Permission to execute the file.s
–setgid
bit.t
–sticky
bit.
In our example, rw-r--r--
means that the user can read and write the file, and the group and others can only read the file. The number 1
after the permission characters is the number of hard links to this file.
The next two fields root root
are showing the file owner and the group, followed by the size of the file (337
), shown in bytes. Use the -h
option if you want to print sizes in a human-readable format. You can change the file owner using the chown
command.
Oct 4 11:31
is the last file modification date and time.
The last column is the name of the file.
Show Hidden Files
By default, the ls
command will not show hidden files. In Linux, a hidden file is any file that begins with a dot (.
).
To display all files including the hidden files use the -a
option:
$ ls -la ~/
OUTPUT
drwxr-x--- 10 reconshell reconshell 4096 Feb 12 16:28 .
drwxr-xr-x 18 reconshell reconshell 4096 Dec 26 09:21 ..
-rw------- 1 reconshell reconshell 1630 Nov 18 2017 .bash_history
drwxr-xr-x 2 reconshell reconshell 4096 Jul 20 2018 bin
drwxr-xr-x 2 reconshell reconshell 4096 Jul 20 2018 Desktop
drwxr-xr-x 4 reconshell reconshell 4096 Dec 12 2017 .npm
drwx------ 2 reconshell reconshell 4096 Mar 4 2018 .ssh
Sorting the Output
As we already mentioned, by default, the ls
command is listing the files in alphabetical order.
The --sort
option allows you to sort the output by extension, size, time and version:
--sort=extension
(or-X
) – sort alphabetically by extension.--sort=size
(or-S
) – sort by file size.--sort=time
( or-t
) – sort by modification time.--sort=version
(or-v
) – Natural sort of version numbers.
If you want to get the results in the reverse sort order, use the -r
option.
For example, to sort the files in the /va
r
directory by modification time in the reverse sort order you would use:
$ ls -ltr /var
It’s worth mentioning that the ls
command does not show the total space occupied by the directory contents. To get the size of a directory , use the du
command.
List Subdirectories Recursively
The -R
option tells the ls
command to display the contents of the subdirectories recursively:
$ ls -R
Conclusion
The ls
command lists information about files and directories. For more information about ls
visit the GNU Coreutils page or type man ls
in your terminal.
If you have any questions or feedback, feel free to leave a comment.
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