Linux Dummies 9th

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Part IV: Junior Administrator Boot Camp
Putting Wildcard Expansion to Good Use
Computing life would be tedious if you had to repeat the same command
on multiple files. After all, aren’t repetitive tasks what the computer was
designed to do? Wildcard expansion refers to the capability of executing one
command against many files without having to re-enter the command. The
asterisk (*) and the question mark (?) are two wildcard characters that are
used to match any filename, or a portion of a filename. For example, you can
use the following command to see a long directory listing that includes only
files that end with a .doc filename extension:
ls -l *.doc
The files listed may include resume.doc, cover_letter.doc, and to_
editor.doc, for example.
The asterisk wildcard character can match zero or more characters. To match
just a single character, use the question mark.
Working with Long Commands
As you become used to the command line, you should find some shortcuts
to ease your typing chores. In this section, we show you some features of the
bash shell designed to make your life on the command line as pleasant as
possible. These features include automatic command-line completion, editing,
and using the history of previously entered commands.
Asking Linux to complete a command
or filename for you
Considering that you do much more typing on the command line in Linux
than you may normally do in a GUI environment, a feature that provides
typing shortcuts wherever possible is extremely handy. Command completion
is a function of the shell that fills in the rest of the filename and system commands
you start to type.
The capability of the Linux filesystem to deal with practically unlimited sizes
of filenames means that many filenames can become huge. Typing these long
filenames can become cumbersome and error-prone. Fortunately, with command
completion, typing a command or a long filename is short work.