How To Use Ls Command.
This article will show you how to use the ls command through practical examples and detailed explanations of the most common ls options.
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.
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:
file liviu.texts sor : 0 anaconda-ks.cfg file1 liviu.texts.sh substraction.sh archive.tar.gz file2 ll.txt test.py binar.sh file3 music.gz test.txt calculator.sh file.out my test.y database_name-20230503.sql file.text MY_ARR top.clasic.music.sh database_name.sql.gz file.txt myfavoritemusic.gz top.music.sh desktop fillename
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
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.
When the long listing format is used, you can see the following file information:
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
-rw-r--r--. 1 root root 100 Jan 25 20:40 /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 ~/
dr-xr-x---. 10 root root 4096 May 31 16:04 . dr-xr-xr-x. 18 root root 4096 Feb 15 18:17 .. -rwxr-xr-x. 1 root root 144 Jan 28 12:23 Addition.sh -rw-------. 1 root root 1303 Sep 25 2021 anaconda-ks.cfg -rw-r--r--. 1 root root 45 Feb 3 20:23 archive.tar.gz -rw-------. 1 root root 20276 May 31 22:30 .bash_history -rw-r--r--. 1 root root 18 Dec 29 2013 .bash_logout -rw-r--r--. 1 root root 176 Dec 29 2013 .bash_profile -rw-r-----. 1 root root 251 Apr 12 20:19 .bashrc -rwxr-xr-x. 1 root root 560 Jan 28 12:28 binar.sh -rwxrwxrwx. 1 root root 606 Jan 28 12:20 calculator.sh -rw-r--r--. 1 root root 100 Dec 29 2013 .cshrc
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 /var 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.
