Introduction to Vi | 02x00.03-03

Vi is a powerful and efficient text editor that has been a standard in Unix and Unix-like operating systems for decades. This article will introduce you to Vi, including its origins, fundamental concepts, and essential commands that every user should know. Whether you are new to Vi or looking to refresh your knowledge, this guide will help you get started with editing text in Vi.

What is Vi

Vi is a modal text editor originally developed by Bill Joy in the 1970s for the Unix operating system. It stands for "visual editor" and is renowned for its speed and versatility, making it a favorite among programmers and system administrators.

Who is Bill Joy

Bill Joy is an American computer scientist and co-founder of Sun Microsystems. He is also the creator of Vi, which he initially developed while a graduate student at the University of California, Berkeley. Vi was designed to be a lightweight and efficient editor suitable for Unix systems.

How to Start and Exit Vi

To start Vi, open a terminal and type:

vi filename

This command opens Vi and loads the specified file. To exit Vi, you can use several commands depending on whether you've made changes or not:

:q

This command quits Vi if no changes have been made.

:q!

This command quits Vi forcefully, discarding any changes made.

:wq

This command saves changes and exits Vi.

What are the Command and Insert Modes, and How to Switch Between Them

Vi operates in two primary modes:

• Command mode: This is the default mode where you can navigate, delete, copy, and perform other operations using commands.
• Insert mode: In this mode, you can insert and edit text directly into the document.

To switch from command mode to insert mode, press:

i

To switch from insert mode back to command mode, press:

Esc

How to Edit Text

In command mode, you can navigate and edit text using various commands:

• h: Move left
• j: Move down
• k: Move up
• l: Move right
• x: Delete character under cursor
• dd: Delete current line
• yy: Yank (copy) current line

How to Cut and Paste Lines

To cut (delete) a line, use:

dd

To paste (insert) a line, move the cursor to the desired location and press:

p

How to Search Forward and Backward

To search forward in Vi, press:

/search_term

To search backward, press:

?search_term

How to Undo

To undo the last change in Vi, press:

u

How to Quit Vi

To quit Vi and save changes, if any, press:

:wq

To quit Vi without saving changes, press:

:q!

Conclusion

Vi is a robust text editor renowned for its efficiency and flexibility. Mastering its basic commands and modes will significantly enhance your productivity, especially in Unix environments. As you continue to use Vi, you'll discover its rich set of features that make it a preferred choice for many users.