Introducing vi:
The vi text editor uses two main
modes: command mode and insert mode. The first part of this tutorial focuses on
navigating a file, which is done in command mode. When you're in command mode,
normal key presses are used to execute commands rather than to create text.
When you enter insert mode, the keyboard is used to enter text, for instance,
on the command line. To exit command mode, press the Esc key.
Commands in vi can be either
single key presses, combined key presses using Shift or Ctrl, or key sequences.
Any time a capital letter is referenced for a command, you should use the Shift
key combined with that letter. Any time a command is referenced that uses two
letters or symbols, you press the keys in sequence rather than simultaneously.
To begin, you'll create a blank
file by opening vi from the command line followed by the name of your new file.
In this tutorial, you make a document from scratch in vi and edit the document
to learn useful vi commands. By the end of the tutorial, you'll have learned all
the major vi commands that are used in day-to-day editing, as well as some
powerful commands that you can leverage when the time is right.
Log in to your favorite UNIX-like
operating system and open vi with a new file. Open vi with a new file
$ vi tutorial.txt
vi opens with a new blank file
called tutorial.txt You'll immediately
notice something odd: The far left column of the text editor is filled with
tilde characters. Don't worry --that's how vi illustrates undefined portions of
the document. In other words, these lines don't exist yet, because the file has
no content.
Before you do anything else, you
should learn how to save a file and how to exit vi. These types of commands are
entered by pressing the colon key followed by a sequence of letters describing
your desired action. To save your new file, press the colon key, press the w
key, and then press the Enter key. To quit vi, press the colon key, the q key,
and the Enter key. Now, open vi again on the command line. If you try to exit
vi without saving your changes, it warns you to press the exclamation point key
to confirm your action. Any time you want to override a system warning, append
your key sequence with an exclamation point; the key sequence to quit is : key, q key, ! key, Enter key
You can combine commands, such as
wq, to save the file and then exit vi.
The first thing you need to do is
insert some text so that you can learn to edit and manipulate your file. By
default, you start in command mode. So, if you just start typing, you might be
surprised by the results. Each mode is described in detail later; for now,
press the i key to enter insert mode, and then type a few lines of text as you
would in a normal text editor. When you're finished, press the Esc key to get
back into command mode.
When you enter insert mode, the
bottom line of the editor indicates you have done so Type some text lines in your
example document so that you have text to work with After you press the Esc key, the
cursor remains on the last character typed, and you're back in command mode.
The next section teaches you how to navigate the file.
Navigating in vi:
In command mode, your keyboard
becomes an interface tool, as opposed to a text-input tool. vi is designed for
users that need access to all common commands while keeping their hands on the
home keys (a-s-d-f and j-k-l-;) and reaching to nearby letters. The first basic
operation to learn is moving the cursor. Most modern versions of vi allow you
to use the arrow keys on the keyboard, but advanced vi users prefer the easily
accessible keys under their fingertips, h-j-k-l:
• h and l represent left and
right, respectively, which is intuitive because they bound the four navigation
keys on the left and on the right.
• k moves the cursor up.
• j moves the cursor down.
You'll learn these keys quickly
with muscle memory. To move the cursor to the first line of the three-line file
you created, press k two times. The cursor now sits at the end of first line.
Go ahead and use h-j-k-l to move the cursor to other locations in the file, but
then bring it back to the end of line one.
Move the cursor back to the first
line of the file with the h-j-k-l directional keys
Moving the cursor with shortcuts:
Moving within a line
Now that your cursor is at the
end of first line, you might want to move it to the beginning of the line, but
you don't want to click h over and over again to get there. In command mode, vi
has keyboard-based shortcuts that let you navigate rapidly to various locations
in the file more quickly than you could by moving your hand over to the mouse
and pointing to the location in the file you want to go to, or using arrow keys
to traverse spaces one by one. The first such shortcut is 0 (zero):
• To go to the beginning of a
line, press 0; your cursor jumps to that location.
• To go back to the end of the
line, press $. Go ahead and try it.
Now you can move one character at
a time. You can also move to the beginning and end of each line, but those are
two widely varying granularities. Another option is to navigate word by word.
You can do so with the w and b keys:
• Pressing w moves forward one
word.
• Pressing b moves back one word.
Try it by moving to the beginning
of the first line (by pressing 0) and then move to the beginning of the word
test by pressing w three times. Then, press b twice to get back to the word is.
You probably noticed that the w
key and the b key set the cursor to the beginning of each word. You can also
navigate to the end of each word by using the e key to move forward, or by
pressing g. Press e to go backward.
Moving the cursor word by word
with w and b is a good way to quickly navigate to a word you misspelled or
would like to change
Moving from line to line:
Now, you can quickly move within
a line but, as you deal with larger files, it's also important to rapidly
navigate from line to line. There are a few ways to do this in vi. You can use
the up and down commands (k and j), or you can use the page-up and page-down
commands. Most commands in vi don't require you to press the Ctrl key, but the
page-up and page-down commands are a couple of exceptions to this loose rule:
• Press Ctrl-u to go up a page.
• Press Ctrl-d to go down a page.
To quickly navigate to the
beginning or end of a file, you can use gg or G:
• Pressing gg puts the cursor on
the first line of the document.
• Pressing G puts the cursor on
the last line of the document.
Inserting and editing in vi:
While navigating the document,
you remain in command mode and use the keyboard as an interface tool to move
the cursor. The next set of command mode keys provide different ways to enter
insert mode, which is used to input new text into your file. You used the most
basic way to enter insert mode at the beginning of this tutorial when you
entered your initial text: You pressed the i key, which stands for insert.
Pressing i puts you into insert mode in front of the current cursor location.
For instance, if you navigate to
the beginning of the file by pressing gg, you can press i, which makes any text
you enter appear prior to the text on the current line. Press gg, i, and then
type I am inserting new text with i. Press the Esc key when you're finished to
go back to command mode. Remember, you must go back into command mode after
entering new text, or there is no way to navigate the document.
The simplest way to add new next
is to use the i key to enter insert mode
The other basic method of
entering new text is to use the a key, which stands for append. Using the a key
puts you into insert mode, but it adds text after the current location of the
cursor instead of before the current location of the cursor. To test this, go
to the last line of your document and press the G and $ key to go to the end of
the line. Then press the key, type Pressing a appends text, and press the Esc
key to return to command mode.
Another way to insert text is
with the a key, which stands for append Now your cursor is at the period on the
last line of your file. If you press the i key now, you'd insert text just
before the period. If you press the a key, you'd insert text just after the
period. By pressing the I key (the capital letter), you can start your input at
the beginning of the line, even though your cursor is at the end of the line.
Similarly, if you press the capital A key, you can input text at the end of the
line regardless of the cursor position. To test this, press I, type I think ,
and then press the Esc key.
To insert text at the beginning
of a line (regardless of cursor position), press the I key Another useful way
of inserting new text is to simultaneously enter insert mode and add a new line
to your text file. Just like the normal text insertion, this can be done before
or after the cursor location:
• To insert a new line above the
current cursor location, press the O key.
• To insert a new line below the
current cursor location, press the o key. To try this command, press O, type I
inserted this line by pressing O, and then press the Esc key to return to
command mode.
To insert text
on a new line before the cursor, press the O key
You've now used the major methods
of inserting new text. To recap, the keys are a, i, A, I, o, and O. Can you
remember what each one does? Don't worry, even if you don't, they will come
natural to you after a few days of use.
Replacing text
Now that you've typed a few items
into your tutorial.txt file, you might find that you've made some errors, or
you might want to change your choice of words. Before learning how to delete
text, you should learn how to replace text. Why? Because if you learn to add
new text and delete old text, you might fall into the habit of using the delete
commands when a replace command would be more efficient. It's quicker to
replace a word in a one-step process than it is to delete a word and then add a
new word in its place.
vi uses two important replace
commands. The first is the r key, which removes the character the cursor is
focused on and puts you in insert mode for a single replacement character. In
other words, you can make one keypress after pressing r. As a result, vi
automatically returns to command mode (without pressing the Esc key). To try
this, use the k key and the l key to navigate up to the end of second line.
Your cursor should be focused on a period. To change the period to an
exclamation point, press the r key and then press the! Key.
To replace a single character,
press the r key and then type the character you want in the document
An even more useful replacement
command is executed by pressing the c key and then the w key, which together
stand for change word. This command deletes the current word and puts you in
insert mode so that you can immediately start typing a replacement word. In
this case, you need to press the Esc key when you're finished typing the new
word to let vi know you're done. Move down to the word great, press the c and w
key, type cool, and then press the Esc key.
To replace a
word, press the c and w key and then type the new word
If you want to remove text
altogether rather than replacing it, you need to use a delete command. As with
many other things in vi, you have multiple choices, depending on how much data
you want to delete at once. The most basic delete command is the x key, which
deletes one character at a time. To try it, go back to the beginning of your
text file and press the Ctrl-u (page-up) key. Press the $ key to go to the end
of the line and then press the x key five times to delete the test.
Deleting text
To delete
individual characters, use the x key
Pressing the x key five times did
the job, but you've probably gathered that vi has a quick way of doing just
about everything. You can delete a word with one command by pressing the d key
and w key, which together stand for delete word. Navigate back to the word This
by pressing the b key three times. To delete the word, press the d key and w
key.
To delete
individual words, use the dw command
You're left with a hanging,
partial sentence at the end of the first line. To delete everything on a line
that follows your cursor position, you can use the d key with the $ key, which
you've learned is used for end-of-line operations. Press the d key and the $
key to remove is a from the end of the line.
To delete from
the cursor to the end of a line, use d$
The final commonly used deletion
method in vi is the delete-line command, which is accomplished by pressing the
d key twice. It deletes the text on the line and brings the next lower line up,
so you don't have an empty line in the document. To remove the first line of
your file, press the d key and then press the key again.
To delete an
entire line, press dd.
Speaking of bringing up a line,
you can use the join command by pressing the J key, which brings the line below
the cursor up to the line the cursor is on, without deleting any text. Your
cursor should be on the new line (line 1) of your document.
Press the J
key to bring line 2 up to line 1. To bring two lines together in vi, press the
J key
Getting fancy:
You should now have the basic
skills to create, navigate, and edit a text file in vi. After you get familiar
with the basic commands, you can create and edit files about as quickly as you
can in a more conventional text editor. A few things are missing from your
repertoire, though. This section teaches you how to cut, copy, and paste. You
can do multiple iterations of a command at one time, repeat commands, search
the document, and use undo and redo. This editor meets the major functionality
found in other text editors and uses the fast-access keyboard command style.
Cut, copy, and paste
In vi, any time a piece of text
is deleted, it's automatically stored in a buffer (like the clipboard in
Windows). You already know how to do a cut command by using x, dd, dw, and d$.
Similar commands are available to copy data without deleting it --this process
is called yank in vi --:
• Press the y key twice to copy a
whole line.
• Press the y key and w key to
copy an individual word.
• Press the y key and $ key to
copy a line starting at the current cursor location.
Copying data isn't much use
without knowing how to paste it. So, before testing these commands, you should
learn the paste command, which is enacted with the p key. Like many other
commands in vi, a lowercase p key pastes data after the cursor location,
whereas an uppercase P key pastes data before the cursor position.
To copy and paste, navigate to
the first line of your text file and press the y key twice. Then, move the
cursor down to line 2 and press the p key once. Doing so creates a copy of line
1 on line 3.
To copy a
line, use the yy command and paste using the p command.
Try doing a cut and paste by
moving the cursor to the second line and press the d key twice. Then, press the
p key to paste the line below line 2.
To cut and
paste a line, use the dd command and the p command
Using numbers to preface vi commands
At this point, you might wonder
how to do some of these commands on more than one piece of data at a time. For
instance, you probably often copy and paste entire paragraphs, as opposed to
single lines. vi lets you preface just about every command in the application
with a number, which causes the command to operate multiple times at once. This
is an extremely powerful, important part of what makes vi a great editor for
power users. To try a simple example of cutting and pasting two lines at a
time, navigate to line 1 of the file, press the 2 key, press the d key twice,
and then press the p key.
Cut and paste two lines at a time
by using a number 2 preceding the dd command and the p command
The same concept can be used
during the paste command to replicate a line multiple times. To do so, go back
to line 1, copy the line with the yy command, and then press 10 before pressing
the p key. Now you have 10 more lines of comments about vi. Before moving on,
press the 5 key and then press the d key twice to remove some of the extra
lines.
Paste multiple
lines by preceding the p command with the number 10; then delete some of them
with the number 5 preceding dd
Experiment with numbers in front
of navigation commands as well. For instance, pressing the 30 key and then the
l key moves the cursor 30 spaces to the right. Pressing the 7 key and then the
G key moves the cursor to line 7 in the file. Pressing the 5 key and then the w
key moves the cursor to the fifth word. When you're finished experimenting, you
can move on to the next step.
Repeating vi commands
Another useful command in vi is
executed with the . (period) key. The . key repeats the last command, which is
an important feature for getting work done quickly. For instance, navigate the
cursor to the word cool on the first line, and then use the cw command to
change the word to fast. Don't forget to press the Esc key when you're finished
typing the word fast. Move down to another instance of the word cool, and then
press the . key to change that word to fast. You can also move to the word line
on the last two lines of your file and replace those with the. key.
Repeat
commands with the period key, which lets you produce document edits quickly
Searching text in vi
Searching text in vi is also fast
and efficient. To start searching for a string, press the / key (slash key)
followed by the string you want to search for and then press the Enter key. To
combine some of your vi skills, press the / key, type think, press Enter, and
then use the cw command to change the word to know. Don't forget to press the
Esc key when you're finished.
If you want to do the same thing
on line 2, press the n key to find the next instance of think, and then press
the . key to change the word to know. The ? key does a search just like the /
key, but it searches the document backward instead of forward.
After you've replaced think with
know, press the ? key followed by the word fast to search back to it.
Search for strings by using the
slash key followed by the string you're searching for
Search for strings backward by
using the ? key followed by the string you're searching for
Undo and redo in vi
If you make any mistakes, vi has
the modern convenience of undo and redo to make sure you can restore your
document to the proper state. Undo is accomplished by pressing the u key in
command mode, and redo is executed by pressing Ctrl-r in command mode. Try undo
and redo, as follows:
1. Go to line 3 in your text file
and remove a few lines.
2. Press the 3 key and the G key
to go to line 3.
3. Press the 2 key and the dd
command to delete two lines.
4. Oops! That was a mistake, and
you want to get the two lines back. To do so, press the u key to undo the
previous command.
5. If you change your mind and
want the two lines removed, press Ctrl-r to redo the command.
To undo a command, use the u key;
to redo a command, press Ctrl-r
Wrap-up:
To wrap up, run though a last
sequence of commands to combine some of the things you've learned:
1. To go to the beginning of your
document, press the g key twice.
2. To delete everything in your
file (because you have less than 100 lines), type 100 followed by the dd
command.
3. Press the i key to go into
insert mode.
4. Type I am done with this
tutorial!.
5. Press the Esc key.
6. Press the y key twice, type
100, and then press the p key.
You've now yelled to your
computer 100 times that you're done! Good job; time for a break and a cup of
coffee.
After working through this
tutorial, you should have the knowledge to create and edit files with vi.
Experiment with the commands listed throughout this tutorial, and practice them
by beginning to use vi as your day-to-day text editor. It will slow you down at
first but, in a short time as you memorize the commands and learn when and
where to use them, vi can significantly increase your productivity.
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