Browsing Chinese (Traditional) translation

51.

By default, <command>rm</command> will not remove directories. To remove a directory, you must use the <command>-r</command> option (also can be entered as either <command>-R</command> or <command>--recursive</command>). For example, <screen>rm -r foobar</screen> or <screen>rm -R foobar</screen> or <screen>rm --recursive foobar</screen> will remove the directory <filename class="directory">foobar</filename>, <emphasis role="strong"> and all of its contents!</emphasis>

54.

The <command>df</command> command displays filesystem disk space usage for all partitions (<acronym>df</acronym> stands for <quote>disk free</quote>). <screen>df -h</screen> will give information using megabytes (<abbrev>M</abbrev>) and gigabytes (<abbrev>G</abbrev>) instead of blocks (<command>-h</command> means <quote>human readable</quote>).

56.

The <command>free</command> command displays the amount of free and used memory in the system. <screen>free -m</screen> will give the information using megabytes, which is probably the most useful for current computers.

58.

The <command>top</command> command displays information on the Linux system - processes that are running, system resources including <acronym>CPU</acronym>, <acronym>RAM</acronym> &amp; swap usage, and the total number of tasks being run. To exit <command>top</command>, press <keycap>q</keycap>.

60.

The <command>uname</command> command with the <command>-a</command> options displays all system information, including machine name, kernel name &amp; version, and other details. This command is useful for checking which kernel is in use (<abbrev>uname</abbrev> is short for <quote>unix name</quote>).

62.

The <command>lsb_release</command> with the <command>-a</command> option prints version information for the Linux release in use. For example, typing: <screen>lsb_release -a</screen> will display: <screen>No LSB modules are available.
Distributer ID: Ubuntu
Description: Ubuntu 10.04
Release: 10.04
Codename: lucid
</screen>

64.

The following commands must be prefaced with the <command>sudo</command> command. Please see <ulink url="https://help.ubuntu.com/community/RootSudo">RootSudo</ulink> for information on using <command>sudo</command> (<abbrev>sudo</abbrev> is short for <quote>superuser do</quote>).

66.

The <command>addgroup</command> command is used to create a new group in the system. To create a new group, type: <screen>sudo addgroup foobar</screen> The above command will create a new group called <emphasis role="strong">foobar</emphasis>.

68.

The <command>adduser</command> command is used to create a new user on the system. To create a new user, type: <screen>adduser foobar</screen> which will create a new user called <emphasis role="strong">foobar</emphasis>.

70.

The <command>passwd</command> command is used to assign a new password to a new user or to change the current password for an existing user. To add a password or change the password for the user <emphasis role="strong">foobar</emphasis>, type: <screen>passwd foobar</screen> For new users, this will generate a prompt to enter the new password. For an existing user, there will be a prompt for the existing password before the prompt for a new password.