What is Vi and what can I do with it?

What is Vi?

In the Linux operating system you need a text editor to open and edit a configuration file or any other file.

In Linux - where we mainly use CentOS - you have several well-known text editors, but the most important text editor that is always present by default is Vi . In fact it is always included in the installation of the Linux operating system and therefore you don’t need to install it.

If it is not present you can install it with the following commands vi text editor:

Install CentOS Vi

yum install vim-enhanced -y

Ubuntu Vi install

sudo apt-get install vim

install Debian Vi

sudo apt install vim

The main reasons why it is best to work with the Vi text editor are:

• Vi has many similarities to commands in the operating system
• Very comprehensive yet easy to use
• Is used in every howto on the internet
• Often installed by default with the Linux OS

Basic functions Vi text editor

Although Vi is very user-friendly, you need to know some basic things to be able to use it yourself. Below we explain some of the most common basic functions, and once you have mastered them you will soon be able to use the more advanced functions.

Open file with Vi

First of all, we’ll start by opening a file. This can be a new (empty) file or an existing file you want to view or modify.

Open or create new / empty file with Vi

vi /path/to/journey/new/file

Open existing file with Vi

vi /path/to/existing/file

Once you enter this command, the vi editor will open your chosen file and, in the case of an existing file, display its contents.

Different modes in Vi

So once you have opened the file with Vi you will see the contents of the file you are opening. You can’t edit or modify the file right away, because you’re in the so-called : “Command mode”.

Command mode The Command Mode means that you can enter commands to choose what you want to do. If you don’t enter anything you can see the content and move your cursor through it, but you can’t enter, edit or delete anything.

Insert mode As soon as you want to edit something, you have to choose the so-called : Insert mode. The name says it all, but this is the mode where you can insert / enter and modify or delete things.

Possible commands in Command mode Vi

There are several possible commands or keys in command mode that you can use to get started. The most important ones I will list and explain below:

Navigating through the file in Vi

When you open a file with a lot of content, it is difficult to scroll through easily with your cursor. You will find that it is very slow and not conducive to your productivity.

Fortunately Vi has some nice solutions built in that make it a lot easier and above all faster.

With the commands below you can navigate through the file in Vi much easier. Please note that these commands only work in command mode, so you should not be in insert mode.