Using vi, the Unix Visual Editor


Description
This tutorial describes vi, the full screen editor found on nearly all Unix systems. Basic commands are covered, including those that enable you to insert, delete, change, replace, and copy text, and to move around within and between files. In addition, you will learn how to set editing options for your files, temporarily or permanently, globally or locally.
Outline
A. Vi Basics
  1. About vi
  2. Starting vi
  3. vi Modes
  4. Basic Cursor Movement
  5. Entering, Deleting, and Changing Text
  6. Setting Basic Options in vi
  7. Exiting vi
  8. Basics Summary

B. Intermediate Vi

  1. More On Cursor Movement
  2. Entering Text Mode
  3. Commands and Objects
  4. Replacing and Changing Text
  5. Deleting Text
  6. Copying and Pasting Text
  7. Other Useful Commands
  8. Buffers
  9. Copying, Deleting, or Moving Text Using Line Numbers
  10. Searching for Text
  11. Substitutions

C. Advanced Vi

  1. Writing to and Reading from Files
  2. More About Options
  3. Customizing vi Sessions
  4. Creating a .exrc File
  5. Abbreviations & Mapping

D. Tips and Tricks

  1. Making vi an Editor in Pine
  2. vi-ing More Than One File
  3. Moving the Left Margin
  4. Issuing Shell Commands From vi
  5. Double Spacing a File



A. VI BASICS

 

  1. About vi

    vi is Found on Nearly Every Unix Computer

    vi is Powerful and Fast

    vi Stays Out of Your Way


     

  2. Starting vi

    Open a file with vi. Type: vi myfile.txt


     

  3. vi Modes

    Command Mode

    Insert (or Text) Mode

    When in doubt about which mode you are in, press <Esc>


     

  4. Basic Cursor Movement
    
       
        From Command Mode
         
        k    Up one line
         
        j    Down one line
         
        h    Left one character
         
        l    Right one character (or use <Spacebar>)
         
        w    Right one word
         
        b    Left one word
         
        
       
      

    NOTE: Many vi commands can take a leading count (e. g., 6k, 7e).


     

  5. Entering, Deleting, and Changing Text
       
        From Command Mode
         
        i    Enter text entry mode
         
        x    Delete a character
         
        dd   Delete a line
         
        r    Replace a character
         
        R    Overwrite text, press <Esc> to end
         
      


     

  6. Setting Basic Options in vi

    Displaying Line Numbers

        From Command Mode
         
        :set nu    Display line numbers
         
        :set nonu  Hide line numbers
         

    Setting Right Margin

        From Command Mode
         
        :set wm=number  Set Wrap Margin number of spaces from right
                                     edge of screen
         
        :set wm=10      Set Wrap Margin 10 spaces from right edge
                                     of screen
         
        :set wm=0       Turn off Wrap Margin
         


     

  7. Exiting vi
        From Command Mode
       
           ZZ     Write (if there were changes), then quit
         
        :wq    Write, then quit
         
        :q     Quit (will only work if file has not been changed)
         
        :q!    Quit without saving changes to file
         


     

  8. Basics Summary
      
        UNIX   ---> vi file --->  COMMAND  ---> i I a A o O --->  TEXT 
        SHELL  <---- ZZ <-------  MODE     <------ <Esc> <------  MODE
         
      
    1. A Basic vi Session
      1. To enter vi, type: vi filename <Return>
      2. To enter insert mode, type: i
      3. Type in the text: This is easy.
      4. To leave insert mode and return to command mode, press: <Esc>
      5. In command mode, save changes and exit vi by typing: :wq <Return>

        You are back at the Unix prompt.



B. INTERMEDIATE VI

 

  1. More On Cursor Movement

     

        From Command Mode
       
           e    Move to end of current word
         
        $    Move to end of current line
         
        ^    Move to beginning of current line
         
        +    Move to beginning of next line
         
        -    Move to beginning of previous line
       
         
        G    Go to last line of the file
         
        :n   Go to line with this number (:10 goes to line 10)
       
         
        <Ctrl>d   Scroll down one-half screen
         
        <Ctrl>u   Scroll up one-half screen
         
        <Ctrl>f   Scroll forward one full screen
         
        <Ctrl>b   Scroll backward one full screen
         
       
        )         Move to the next sentence
         
        (         Move to the previous sentence
         
        }         Move to the next paragraph
         
        {         Move to the previous paragraph
        
      
        H         Move to the top line of the screen
         
        M         Move to the middle line of the screen
         
        L         Move to the last line of the screen
       
         
        %         Move to matching bracket:  ( { [ ] } )
         


     

  2. Entering Text Mode
        From Command Mode
         
        i    Insert text before current character
         
        a    Append text after current character
         
        I    Begin text insertion at the beginning of a line
         
        A    Append text at end of a line
         
        o    Open a new line below current line
         
        O    Open a new line above current line
         


     

  3. Commands and Objects
        Format                         Example
         
          operator number object          c2w
         
          number operator object          2cw
         
      
        Operators              
      
          c   change             
      
          d   delete            
      
          y   yank            
      
      
        Objects and Locations
         
          w           one word forward 
      
          b           one word backward
         
          e           end of word
         
          H, M, L     top, middle, or bottom line on screen
         
          ), (        next sentence, previous sentence
         
          }, {        next paragraph, previous paragraph
         
          ^, $        beginning of line, end of line
         
          /pattern/   forward to pattern 
      
      


     

  4. Replacing and Changing Text
        From Command Mode
         
        r        Replace only the character under the cursor.
                           (Note: using r you remain in command mode.)
         
        R        Beginning with the character under the cursor, 
                        replace as many characters on this line as you 
                        want. (You are in overtype mode until you 
                           press <Esc>
    
         
        cw       Beginning with the character under the cursor, 
                           change a word to whatever you type.  (You are 
                        in insert mode until you press <Esc>)
         
        c$       Beginning with the character under the cursor, 
        C               change a line to whatever you type. (You are
                           in insert mode until you press <Esc>)
         


     

  5. Deleting Text
        From Command Mode
         
        x       Delete a character
         
        dw      Delete an alphabetic word and the following space
                          (6dw deletes six words)
         
        dW      Delete a blank-delimited word and the following space
         
        dd      Delete a line (6dd deletes six lines)
         
        d$      Delete all characters to the end of the line.
           D             
      
        d}      Delete all characters to the end of the paragraph.
         
        :5,30d  Delete lines 5 through 30
         

    Deleted text goes into a temporary buffer that is replaced each time you delete (or copy) more text. The current contents of the buffer can be put back into your file.


     

  6. Copying and Pasting Text
        From Command Mode
         
        yy        Copy (yank) the current line 
      
        6yy       Copy (yank) six lines, beginning with the current line
         
        yw        Copy the current word
         
        p         Put the text after the cursor position
         
        P         Put the text before the cursor position
         

    Copied text goes into a temporary buffer that is replaced each time you copy (or delete) more text. Only the current contents of the temporary buffer can be put back into your file. As a result, when you use copy (y), use the put (p) command immediately.

    A yank and put procedure using colon commands:

    1. :5,10y Copy lines 5-10
    2. Move cursor
    3. :put Put after cursor


     

  7. Other Useful Commands
        From Command Mode
         
        .    Repeat last command
         
        n.   Repeat last command n number of times
         
        J    Join next line to current line
         
        u    Undo last single change
         
        U    Restore current line 
         
        ~    Change letter's case (capital to lower and vice versa)
         


     

  8. Buffers

    Temporary Buffer

    Deleted or copied text goes into a temporary unnamed buffer. The contents of the temporary buffer may be retrieved by using the p or P commands.

    
        p   Put words from temporary buffer after cursor or
                      put lines from temporary buffer below current line
         
        P   Put words from temporary buffer before cursor or
                      put lines from temporary buffer above current line
         

    Lettered Buffers

    There are 26 lettered buffers (a-z). Contents of a lettered buffer are saved until you copy or delete more characters into it, or until you quit your current vi session.

     
      From Command Mode
       
         "ayy     Copy (yank) a line into buffer a
         
      "Ayy     Appends to buffer a
         
      "a10yy   Copies 10 lines into buffer a
         
      "a10dd   Deletes 10 lines of text into buffer a 
      
      "ap      Put contents of lettered buffer a below the current line
         

    Both temporary and lettered buffers last only for the current vi session.


     

  9. Copying, Deleting, or Moving Text Using Line Numbers
     
      From Command Mode
       
         :5,10 co 105   Copy lines 5-10 to the line after 105
         
      :5,20 m $      Move lines 5-20 to end of file
         
      :7,300 d       Delete lines 7-300 (to buffer)
         


     

  10. Searching for Text
      From Command Mode
       
         /text   Search forward (down) for text (text can include spaces
                             and characters with special meanings.)
         
      ?text   Search backward (up) for text
         
      n       Repeat last search in the same direction
         
      N       Repeat last search in the opposite direction
         
      fchar   Search forward for a charcter on current line
         
      Fchar   Search backward for a character on current line
         
      ;       Repeat last character search in the same direction
         
      %       Find matching ( ), { }, or [ ] 
      


     

  11. Substitutions

    The simplest way to do substitutions over a range of lines, or throughout the file, is to use the s colon command. The basic form of this command is the following:

         
           :n1,n2s/old/new/gc
       
              n1 is the beginning line 
       
           n2 is the ending line number
         
           s means to substitute text matching the pattern (old) 
                    with text specified by (new)
         
           g (global) is optional.  It indicates you want to substitute 
                    all occurrences on the indicated lines.  If you use 
                    g, the editor substitutes only the first occurrence
                       on the indicated lines.
         
           c (confirm) is optional.  It indicates you want to confirm
                       each substitution before vi completes it.
         
       
      From Command Mode
         
      :%s/old/new/g     Substitutes old with new throughout the file
         
      :.,$s/old/new/g   Substitutes old with new from the current
                                  cursor position to the end of the file
         
      :^,.s/old/new/g   Substitutes old with new from the beginning
                                  of the file to the current cursor position
         
      :&                 Repeats the last substitute (:s) command
         



C. ADVANCED VI

 

  1. Writing to and Reading from Files
      From Command Mode
       
         :w file           Write current file to file
         
      :w>>file          Append current file to file
         
      :5,10w file       Write lines 5 through 10 to file
         
      :5,10w>>file      Append Lines 5 through 10 to file
         
      :r file           Read a copy of file into current file
         
      :!ls              See a list of files in your current directory
         


     

  2. More About Options
      From Command Mode-within vi for the current file only
       
         :set all        Display all options
         
      :set            Display current settings of options
         
      :set nooption   Unset option
         
      :set ai         Set Auto Indentation during text entry
         
      :set ic         Set Ignore Case during searches
         
      :set nu         Show line Numbers 
      
      :set sm         Show Matching ( or { when ) or } is entered
         
      :set wm=10      Set Wrap Margin 10 spaces from right edge of screen
         
      


     

  3. Customizing vi Sessions

    Options can be set four ways:

    1. During a vi session
            
            :set nu
            
                  
    2. In a .exrc file in your home directory.
            Sample contents of a .exrc file
            
                    set nu
                    set ai
                    set wm=10
            
                  
    3. In a .exrc file in a subdirectory.
    4. By setting the EXINIT environmental variable.
            Example of setting the EXINIT environmental variable
            
                    setenv EXINIT "set nu ai ic"
            
                  

      On the Uniform Access systems (Homer, Saul, Mead, Alcott), the EXINIT environmental variable is used to set the shell within which the vi editor operates. Since the EXINIT environmental variable, if it has been defined, overrides anything set by a .exrc file, customizing vi on these computers requires redefining EXINIT. For example, to add numbering and auto indent, you would take the following steps:

      1. Check to see what EXINIT is set to:
        	      % printenv EXINIT
                                 set shell=/bin/csh
                    

        This response indicates that the shell is set to the C shell.

      2. Reset EXINIT:
        	      % setenv EXINIT "$EXINIT nu ai"
                               % printenv EXINIT
                                 set shell=/bin/csh nu ai
                    

    Order of Precedence

    1. If a .exrc file exists in the current directory, vi reads it when beginning a session.
    2. If no .exrc file exists in the current directory, vi checks the home directory for a .exrc file. If such a file exists, vi reads it when beginning a session.
    3. If no .exrc file is found, vi uses its defaults.
    4. Values set in the EXINIT environmental variable override any values set in a .exrc file.


     

  4. Creating a .exrc File
    1. At the system prompt, type: vi .exrc
    2. Type the following commands, each on a separate line:
       
            
            set ai
                  set ic
                  set nu
                  set wm=8
                

      Do not leave blank lines at the beginning or end of the .exrc file.

    3. When you are finished, type: <Esc> ZZ


     

  5. Abbreviations & Mapping

    Abbreviations are text strings that automatically expand into larger strings during insert mode.

      From Command Mode
         
      :ab UW University of Washington
         

    Mapping defines a single key to execute a sequence of keystrokes when the single key is pressed in command mode. In the following example,the @ key is mapped to replace the current word with "University of Washington". The <Control>v allows you to enter the <Esc> key into the command sequence.

    
      From Command Mode
         
      :map @ cwUniversity of Washington <Control>v <Esc> <Return>
         

    Mapping can also be used to call commands external to vi, such as sort or fmt. In the following example, the @ sign is mapped to the sort command, so that the current paragraph (indicated by the }) will be sorted. The <Control>v allows you to enter the <Return> key into the command sequence. The second <Return> completes the map command.

    
      From Command Mode
         
      :map @ !}sort <Control>v <Return> <Return>
         

    Note: You can also put abbreviation and mapping commands in your .exrc file.



D. TIPS AND TRICKS

 

  1. Making vi an Editor in Pine
    1. In your home directory, type: vi .pinerc
    2. Find the line that reads
      
        
             editor=
                   
    3. Change it to read
        
             editor=vi
                   
    4. Write and quit the file. (ZZ or :wq)
    5. Start Pine
    6. In Pine in Compose mode, when you are ready to enter message text, you will see there is an option available called Alt Edit. (Alternate Editor). To evoke the Alternate Editor mode, press: <Cntrl><Shift>_

      When finished editing in vi, exit vi and you will be returned to the compose screen.


     

  2. vi-ing More Than One File

    You can edit more than one file at a time with vi.

      From The Unix Shell Prompt
       
         vi file1 file2   vi two (or more) files at the same time
         
      From Command Mode
       
         :n               Move to file2 from file1
         
      :rew             Rewind back to file1
         
      :e!              Restore original file1 file2 (start all over)
         
      ZZ               Save and quit file. (Must be done for each file.) 
      


     

  3. Moving the Left Margin

    When you print a file you may want the left margin moved to the right. This leaves room for a three-hole punch.

      From Command Mode
         
      :1,$>               Move entire file 1 shift width (eight spaces) 
    		      to the right
         
      :1,$<               Move entire file eight spaces to the left
         
      :%s/^/        /g    Insert any number of spaces at the
                             beginning of each line in the entire file.
                             Simply press the space bar the
                             desired number of times.
         
      :20>>                Moves next 20 lines over 1 shift width.
         


     

  4. Issuing Shell Commands From vi

    You can issue a single shell command while in the vi editor. For example, to list the files in your directory (ls), follow these steps:

      From Command Mode
         
      :w     Write changes to your file (just in case).
         
      :!ls   List contents of your current directory on the screen.
         
      Press <Return> to return to vi.
         

    You can issue many shell commands by temporarily leaving the vi editor.

      From Command Mode
         
      :w     Write changes to your file.
         
      :sh    Return to the shell to enter a number of commands
                without leaving vi. 
       
      Press <Control>d to return to vi editing.
         


     

  5. Double Spacing a File

    Occasionally, you may want a double spaced version of your file for editing or review.

      In Command Mode
        
      :w original.backup Save a backup copy of the original file
       
         :%! sed G          Double space the entire file.
         
      :1,5! sed G        Double space the lines from 1-5.
         


This tutorial has been adapted from course notes developed by Rick Ells and Kathryn Sharpe. The original copyright notice is reproduced below.


© Copyright 1996 University of Washington Computing & Communications.
Permission to reprint or adapt sections from these class notes for noncommercial purposes is granted, provided that the source is acknowledged. Inquiries may be submitted to rells@cac.washington.edu.
Your comments on this class are welcome. Please send email to rells@cac.washington.edu

Class notes URL: http://weber.u.washington.edu/~rells/R110/
Last Modified: August 1, 1996