Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 11-05-2007, Руководство по установке

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IMPORTANT: No News Is Good News
The shell is not verbose: in contrast to some graphical user interfaces, it usually
does not provide confirmation messages when commands have been executed.
Messages only appear in case of problems or errors.
Also keep this in mind for commands to delete objects. Before entering a
command like
rm
for removing a file, you should know if you really want to
get rid of the object: it will be deleted irretrievably, without enquiry.
Using Commands without Options
Look at the structure of commands using a simple example: the
ls
command, used to
list the contents of a directory. The command can be used with or without options. En-
tering the plain
ls
command shows the contents of the current directory:
Figure 17.2 The ls Command
Unlike in other operating systems, files in Linux may have a file extension, such as
.txt
, but do not need to have one. This makes it difficult to differentiate between files
and folders in this output of the
ls
. By default, the colors can give you a hint: directories
are usually shown in blue, files in black.
Using Commands with Options
A better way to get more details about the contents of a directory is using the
ls
com-
mand with a string of options. Options modify the way a command works so that you
can get it to do specific tasks. Options are separated from the command with a blank
Working with the Shell 333