Long listing format linux

ls Command in Linux for Listing Files

If you are a regular Linux user, there must hardly be a day when you haven’t used ls command. A very simple yet powerful command used for listing files and directories. By default, it will list the content of the current directory.

In this article, I will show you ls command in Linux to list files with examples.

1) Run ls without parameter

Running ls without parameter will display a list of files and or directories only. No other information can be seen from the output

2) Use long listing format

Using -l character (small L letter), will display a long listing of the content of current directory ( i.e. not only prints the name of the file, but also some attributes such as owner, group owner, link count, permissions).

Here’s how to read the output :

1st column

The first letter d does the content is directory or file. On the screenshot above, Desktop, Documents, Downloads and lynis-1.3.8 are directories. If it — (minus sign) it means that the content is file. While if it equal with l (small L character), means the content is link file.

The next 9 character is about file permission. With the first 3 rwx characters are for Owner of the file, the second 3 characters are for Group owner of the file and the last 3 characters are for worldwide access to the file.

2nd column
This tells us about how many link to this file

3rd column
This tells us about who is the owner of the file/directory

4th column
This tells us about who the group owner of the file/directory

5th column
This tells us about the size of the file/directory in bytes unit. Except for directories, the size will always count as 4096 bytes

6th column
This tells us about the last time and date the file is modified

7th column
This tells us the filename or directory name

3) Show the size of file

Reading size in bytes unit can confuse us. To read 6,5 M is easier compare with reading 6727680 byte. To do this, we can use -h combine with -l parameter. -h parameter means human readable

Another parameter that can do this is —si parameter. This parameter is similar with -h parameter, but —si powers 1000 while -h powers 1024.

4) Sort file size

After we can show the file size, we may want to sort it by file size. We can use -S parameter to to this. The list will be sort by the largest file size first.

5) Scaling size

Ls can scale size by before printing them using —block-size=SIZE. Where SIZE are :

• K = Kilobyte
• M = Megabyte
• G = Gigabyte
• T = Terabyte
• P = Petabyte
• E = Exabyte
• Z = Zettabyte
• Y = Yottabyte

For example, we want to scale size using Megabyte units. So the syntax will be like this :

6) Show hidden files

In Linux, a file begins with “.” (dot sign) is a hidden file. To show it on ls command, we can use -a parameter.

7) List directory entries only

If we want to list directory entries only, we can use -d parameter.

8) Print entries without owner information

To do this, we can use -g parameter.

9) Print entries without group information

While -g is to suppress owner information, -G will suppress group information

10) Print UID and GID

If we want to know the UID and GID of owner and group owner, we can do it using ls command with -n parameter. Here’s a sample.

From the example above, we know that user pungki has UID = 1000 and GID = 1000. While root group has GID = 0

11) Print with no color

Some Linux distribution is enable color options to ls command. This will make ls print the list in color. If you don’t want it, you can use —color=never parameter.

12) Print the index number of each file

To print the index number or known as inode number, we can use -i parameter. The index number will appear at first column.

13) Add / (slash sign) to mark directory

Appends forward slash to the directories. To do this, use -p parameter.

14) Reverse order while sorting

You may also want to list entries in reverse order. To do this, we can use -r parameter.

15) List subdirectories recursively

With -R parameter, you can list directory including its subdirectories.

16) Sort by extension

You can sort the list by extension using -X parameter or —sort=extension.

Or

17) List by modification time

Using -t parameter will sort the list by modification time which the newest first.

18) List your home directory

For listing your home directory, we can short the directory using «

» (tilde sign). So you don’t have to type your full directory name. Let say if the home directory name is /home/pungki, then

sign have the meaning with /home/pungki.

19) List parent directory

Whenever you are inside a directory, you can also list the parent directory without need to type directory full name. Here’s a sample.

This will list the contents of the directory one level above.

This will list the contents of the directory two level above.

20) File Search

a) Search files ending with letter ‘l»

b) Search files ending with 5 characters

Note — The directory should have files with 5 characters in length otherwise it wont give any outputs.

In the above examples, it didn’t display one file because it had 6 character

Recursively search for the same

c) Search using regex

21) Print the version of ls command

To print it, use —version parameter

That’s some parameters which can be used on day-to-day operation. Of course, you can always consult with ls manual page by typing man ls or ls —help on your console to explore more detail.

21) Print the version of ls command

To print it, use —version parameter

That’s some parameters which can be used on day-to-day operation. Of course, you can always consult with ls manual page by typing man ls or ls —help on your console to explore more detail.

21) Print the version of ls command

To print it, use —version parameter

That’s some parameters which can be used on day-to-day operation. Of course, you can always consult with ls manual page by typing man ls or ls —help on your console to explore more detail.

welcome@12345 welcome@34567 welcome@65467 welcome@65678 welcome@65789

21) Print the version of ls command

To print it, use —version parameter

That’s some parameters which can be used on day-to-day operation. Of course, you can always consult with ls manual page by typing man ls or ls —help on your console to explore more detail.

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How to Use the ls Command in Linux

Listing Directory Contents with ls:

You can list the contents of your current working directory with ls. This is the most common usage of ls.

To list the contents of your current working directory, run ls as follows:

As you can see, the directory contents of my current working directory (which is the login user’s HOME directory by default) is listed.

You can also list the contents of another directory using the full/absolute path or relative path of that directory.

For example, let’s say you want to list the contents of the /etc directory. To do that, run ls as follows:

As you can see, the contents of the /etc directory are listed.

Again, let’s say, you want to list the contents of the

/Downloads directory using the relative path of the directory from your current working directory which the login user’s HOME (

) directory by default.

To do that, run ls as follows:

As you can see, the contents of the

/Downloads directory are listed.

Listing Hidden Files with ls:

On Linux, files and directories starting with . (such as .profile, .bashrc, .local/ etc) are hidden files and directories. By default, the ls command does not list them. But you can use the -a option of ls to list hidden files and directories.

As you can see, the hidden files and directories are listed.

You can also use the -A option of ls to list hidden files and directories. The good side of this option is that, it does not list the . (current directory) and .. (parent directory) directories as -a option does. It may be helpful for shell scripting.

If you compare the output with the previous one, you should see that there is no more . and .. directory in the list.

Enable and Disable Colored Output:

You can enable and disable the colored output of the ls command using the –color option. The –color option takes 3 values, never, always and auto.

On almost every modern Linux distribution, the colored output is enabled by default. If you don’t like the colored output of ls, use –color=never with ls.

If for any reason, you don’t have colored output by default, you can use –color=always with ls.

If you only want colored output when the standard output (STDIN) is connected to a terminal, then you can use –color=auto.

For example, let’s disable the colored output of ls,

As you can see, the colored output is disabled.

Long Listing Format of ls:

The ls command has an awesome long listing format. In the long listing format, you can see the file and directory permissions, file size, the owner and primary group of the files or directories, the number of hard links or the depth of the directory, last modification date, and the name of the files and directories.

The -l option of ls is used to enable long listing format.

As you can see, all the information I told you about is displayed nicely.

This is the directory or file permission section. For directories, this section starts with d and for files, it starts with –. Then the first 3 characters are for user permissions, then the next 3 characters are for group permissions, then the last 3 characters are for others permissions. The character r = read, w = write and x = execute permission. – just means no value is set.

This section represents the number of hard links for files and the depth for directories.

You have the owner and primary group of the file or directory respectively here.

Here, you have the total file size in bytes. You can change the unit with other ls options which I will cover in the next section of this article.

Here, you have the last modification date of the file or directory.

Finally, you have the filename or the directory name.

Changing the File Size Unit in Long Listing Format of ls:

In ls long listing format, by default the file size unit used is bytes. But, you can easily change that with the –block-size option of ls.

To set the unit to kilobytes, use –block-size=k

To set the unit to megabytes, use –block-size=M

To set the unit to gigabytes, use –block-size=G

To set the unit to petabytes, use –block-size=P

As you can see, the file sizes are printed in megabyte unit. This will give you incorrect results as the file sizes are rounded.

Printing Human Readable File Sizes in Long Listing Format of ls:

In the earlier section, you saw how specifically defining file size unit gives incorrect results. Luckily, you can use the -h option of ls to print the file sizes in human readable format, that is, the unit will change depending on the actual file size. So, you will get the correct file size output.

As you can see, the required file size units are used. The output is also accurate.

Printing inode Numbers with ls:

You can print the inode number of files and directories with the -i option of ls.

As you can see, the inode number of all the files and directories are printed before the file and directory name.

Printing SELinux Contexts with ls:

You can print the SELinux contexts of files and directories with the -Z option of ls if you have SELinux enabled on your machine.

As you can see, the SELinux contexts are printed.

Getting Help:

For more information on ls, you may check out the man page of ls with the following command:

So, that’s how you use the ls command in Linux. Thanks for reading this article.

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