Datasheet
28
Phase 1
Working on the Command Line
There’s a great deal more depth to Vi than is presented here; the editor is quite capable, and
some Linux users are very attached to it. Entire books have been written about Vi. Consult one
of these, or a Vi Web page like http://www.vim.org, for more information.
Saving Changes
To save changes to a file, type :w from command mode. This enters ex mode and runs the w
ex-mode command, which writes the file using whatever filename you specified when you
launched Vi. Related commands enable other functions:
Edit new file The :e command edits a new file. For instance, :e /etc/inittab loads /etc/
inittab for editing. Vi won’t load a new file unless the existing one has been saved since its
last change or unless you follow :e with an exclamation mark (!).
Include existing file The :r command includes the contents of an old file in an existing one.
Execute an external command The ex-mode command :! executes the external command
that you specify. For instance, typing :!ls runs ls, enabling you to see what files are present
in the current directory.
Quit Use the :q command to quit from the program. As with :e, this command won’t
work unless changes have been saved or you append an exclamation mark to the command
(as in :q!).
You can combine ex commands such as these to perform multiple actions in sequence. For
instance, typing :wq writes changes and then quits from Vi.
Criteria for Completion
To complete this task, you must successfully edit a copy of your lilo.conf file to add a new
kernel. You don’t need to test the copy of the file, but you should verify that it’s been modified
as you desired. To do so, use cat or less.
Task 1.6: Manage Accounts
As a multi-user OS, Linux requires that users have accounts. This requirement is part of
Linux’s security system, so you shouldn’t try to bypass account management or give it short
shrift—say, by letting many people share an account. Instead, you should learn how to create,
delete, and otherwise manage Linux accounts.
Most Linux distributions provide GUI tools for account management.
Although these tools are perfectly capable of handling routine account main-
tenance tasks on small systems, they differ from one distribution to another.
The text-based tools described here are much more consistent across distri-
butions and are the tools tested on Linux certification exams.
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