====== Vi Editor Exercise 1 ======

===== Preparation =====

** WARNING: **
  * In this exercise /etc/passwd is used, as it exists in every UNIX system.\\ However it is not advised to use "vi" for user management!

  -  Copy the file **/etc/passwd** to your **HOME-directory.** \\ Name your copy **mypasswd** \\ Hint: your HOME-directory is the base directory for you as a user.


===== vi mypasswd =====

HINTS:
  * After you've inserted text, immediately return to **Command Mode**
  * Use the vi-option  **:set showmode**

  -  Above the first line of this new file, add the line: **This is just a test file!** \\ Hint:  **O** (capital o)
  -  Add a new user to your test file.\\ Hint:  **yyp**
  -  See to it that the last line becomes the last line but one.\\ Hint:  **ddp**
  -  For the last 5 user accounts add the comment:  **UNIX user** \\ Hint:  The comment field is the 5th field in the passwd file. \\ Hint:  Use the vi repeat command to make things painless.
  -  Make each line start with one TAB.\\ Hint:  Regular Expression characters **^ $** \\ Hint:  **:1,$s/ / /**
  -  Try to undo your last change.\\ Hint:  **u**
  -  Use vi to copy all administrative users to a file called **passwd.adm**\\ Hint: Administrative users are users like "root" and "lp".\\ This example shows how to copy lines to another file:<code>
"a5yy
"b3yy
..
..
:e passwd.adm
"ap
"bp
</code>
  -  Quit vi.\\ Check if you have a file named **.exrc** in your HOME-directory. Make a backup copy of your existing **.exrc** \\ Create the file $HOME/.exrc containing the following two lines:<code>
:set showmode
:set list
</code>
  -  Use vi to reopen your test file and check which vi-options are available.\\ Hint:  **:set all**
  -  In your test file, pick one of the user accounts and use <space> to add a blank at the end of the login shell field.\\ Is this blank visible? \\ Which vi-option will make it visible?\\ What do you think? Would it stll be possible to login with a blank after the shell in the real /etc/passwd? \\ Remember this option! It's an invaluable option in debugging a non functioning config file!

====== . ======
Copyright (C) 2011 Integrated Services; Tux4u.nl\\
Author: Ing.J.M.Waldorp\\
vi-exercise1 20030514, 20110417