2. A text
editor is one of the most essential tools
provided with the Linux operating system.
With an editor, you can create and modify text files
that have a variety of applications:
System files
Shell programs
Documents
Mail messages
Basically, editors enable you to
insert, delete, move, and search text ranging from
individual characters to thousands of lines.
Two of the most popular editors for Linux system
are emacs and vi.
3. •
VI editor is a basic text editor that is an
acronym of
‘ visual editor’ and was originally written by Bill
Joy in 1976.
•Basically there are three types of editors
available in UNIX; these are named as ‘ed’ ‘ex’
and ‘vi’.
• The ‘ed’ is a line editor and is just like EDLIN
program in DOS.
• The ‘ex’ editor is an advanced version of ‘ed’
that is more user friendly comparative to ‘ed’.
• The ‘vi’ is a screen editor and compared to ‘ed’
or ‘ex’ it is quite better.
4. There are following way you can start using vi
editor:
Command
Description
vi
Create a unnamed file.
vi filename
Creates a new file if it already does not exist,
otherwise opens existing file.
vi -R filename Or view Opens an existing file in read only mode.
filename
vi +n filename
Where n represents the line number where
vi will place its cursor in filename.
5. •Command
mode: This mode enables you to perform
administrative tasks such as saving files, executing
commands, moving the cursor, cutting (yanking) and
pasting lines or words, and finding and replacing. In this
mode, whatever you type is interpreted as a command.
•Insert
mode: This mode enables you to insert text into
the file. Everything that's typed in this mode is interpreted
as input and finally it is put in the file
•.
•Ex mode: In ‘ex’ mode the user is permitted to give
commands at the last line known as command line .This
mode prompts the user to file handling like as saving the
file or exit the editor with or without saving the file.
6. Command
Description
i
insert text before cursor, until <Esc> hit
I
insert text at beginning of current line,
until <Esc> hit
a
append text after cursor, until <Esc> hit
A
append text to end of current line ,
until <Esc> hit
o
open and put text in a new line below
current line, until <Esc> hit
O
open and put text in a new line above
current line, until <Esc> hit
7. Command
Description
:w
Saves file and remains in editing
mode
:x or zz
Saves file and quits editing mode
:wq
Saves file and quits editing mode
:q
Quits editing mode
:q!
quits the file without saving changes
to exit from the editor.
8. Command
Description
b
Beginning of previous word
w
Beginning of next word
e
End of current/next word
0(Zero)
Beginning of line
$
End of line
(
Beginning of current/previous sentence
)
Beginning of next sentence
{
Beginning of current/previous paragraph
}
End of current paragraph
10. Command
Description
x
Nx
delete single character under cursor
delete N characters, starting with character under cursor
X
Deletes the character before the cursor location.
dw
Ndw
delete the single word beginning with character under
cursor
delete N words beginning with character under cursor.
d^
Deletes from current cursor position to the beginning of
the line.
d$
Deletes from the current character to the end of the line.
dd
Ndd
delete entire current line
delete N lines, beginning with the current line;
e.g., 5dd deletes 5 lines
dg
Deletes all the line from the current one to the end of the
file.
11. Moving sections of text around in a file basically requires
three steps:
1)
“Yank” the text into a buffer.
2)
Move the cursor to where you want to insert the text.
3)
Place the text from buffer at the new location.
Command
Description
yy
yank (copy) a line
2yy
yank 2 lines
yw
yank word
y$
yank to end of line
p
put (paste) the clipboard after cursor
P
put (paste) before cursor
12. Command
Description
/pattern
search for pattern
?pattern
search backward for pattern
n
repeat search in same direction
N
repeat search in opposite direction
:%s/old/new/g
replace all old with new throughout file
:%s/old/new/gc
replace all old with new throughout file with
confirmations
