Quick Start Guide

To list all “versions” of myfile.txt, enter

ls -l myfile?.txt

Note that you can only use the ? wild card here because the number-

ing of the les is single-digit. As soon as you have a le named

myfile10.txt you must to use the * wild card to view all versions of

myfile.txt (or add another question mark, so your string looks like

myfile??.txt).

To remove, for example, version 1-3 and version 5 of myfile.txt,

enter

rm myfile[1-3,5].txt

2d Check the result with

ls -l

Of all myfile.txt versions only myfile4.txt should be left.

You can also combine several wild cards in one command. In the example above, rm

myfile[1-3,5].* would lead to the same result as rm myfile[1-3,5].txt because

there are only les with the extension .txt available.

NOTE: Using Wildcards in rm Commands

Wildcards in a rm command can be very useful but also dangerous: you might

delete more les from your directory than intended. To see which les would be

aected by the rm, run your wildcard string with ls instead of rm rst.

17.7 Editing Texts

In order to edit les from the command line, you will need to know the vi editor. vi

is a default editor which can be found on nearly every UNIX/Linux system. It can run

several operating modes in which the keys you press have dierent functions. This

does not make it very easy for beginners, but you should know at least the most

basic operations with vi. There may be situations where no other editor than vi is

available.

Basically, vi makes use of three operating modes:

command mode

In this mode, vi accepts certain key combinations as commands. Simple tasks

such as searching words or deleting a line can be executed.

insert mode

In this mode, you can write normal text.

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