Translations by Heiki Nooremäe

Virtually all commands understand the <command>-h</command> (or <command>--help</command>) option which will produce a short usage description of the command and its options, then exit back to the command prompt. Type: <screen>man -h</screen> or <screen>man --help</screen> to see this in action.

The <command>touch</command> command is used either to change a file's access and modification timestamps or to create a new empty file. For example, <screen>touch foo</screen> will create a new empty file named <filename>foo</filename>. If <filename>foo</filename> is already a file, then using <command>touch</command> will update the timestamps on the file which will show the last time a file was <emphasis>touched</emphasis>.

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>

Every command and nearly every application in Linux has a <abbrev>man</abbrev> (manual) file. It is as simple as typing <command>man command</command> to bring up a longer manual entry for the specified command. For example: <screen>man mv</screen> brings up the <command>mv</command> manual.

<ulink url="http://ss64.com/bash/"/> - an A-Z index of the Bash command line for Linux.

<ulink url="https://help.ubuntu.com/community/CommandlineHowto">Commandline Howto</ulink> - longer and more complete than this basic guide; still not finished however.

Options can be grouped in clusters, so <screen>ls -sh</screen> is the same command as <screen> ls -s -h</screen> Most options have a long version, prefixed with two dashes instead of one, so <screen>ls --size --human-readable</screen> is also the same command as <screen>ls -sh</screen>

This guide describes some basic GNU/Linux shell commands. It is not intended to be a complete guide to the command line, just an introduction to complement <phrase>Kubuntu</phrase>'s graphical tools.

"Under Linux there are GUIs (graphical user interfaces), where you can point and click and drag, and hopefully get work done without first reading lots of documentation. The traditional Unix environment is a CLI (command line interface), where you type commands to tell the computer what to do. That is faster and more powerful, but requires finding out what the commands are." -- from <placeholder-1/>

Text copied from a web page using <keycombo><keycap>Ctrl</keycap><keycap>C</keycap></keycombo> won't paste with <keycombo><keycap>Ctrl</keycap><keycap>V</keycap></keycombo> as it does in other applications because the terminal uses a different combination for paste, <keycombo><keycap>Shift</keycap><keycap>Insert</keycap></keycombo>. Pasting can also be done using the mouse by <mousebutton>right-clicking</mousebutton> in the terminal and selecting <guimenuitem>Paste</guimenuitem> from the menu.

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>.

<emphasis role="strong"><emphasis>command</emphasis> --help</emphasis> and <command>man</command><emphasis role="strong"><emphasis>command</emphasis></emphasis> are the two most important tools at the command line.

<ulink url="http://rute.2038bug.com/index.html.gz"/> - a massive online book about system administration, almost all from the command line.

For more detailed tutorials on the Linux command line, please see:

Deletes from the current cursor position to the end of the line

Tab is a useful feature. It autocompletes any commands or filenames if there is one option, otherwise it displays a list of options that fit the information entered. Using tab in this way reduces typing errors.

Scrolls backwards through the commands entered previously

Scrolls forward through previous commands

Moves the cursor to the <emphasis>start</emphasis> of the line

Moves the cursor to the <emphasis>end</emphasis> of the line

<screen>man intro</screen> is especially useful. It displays the <quote>introduction to user commands</quote> which is a well-written, brief introduction to the Linux command line.

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>.

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>.

To assign the user <emphasis role="strong">foobar</emphasis> to the group <emphasis role="strong">barfoo</emphasis>, type: <screen>adduser foobar barfoo</screen>

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.

All command names, file names or paths to directories will be shown using a <command>monospace font</command>.

This document provides a brief description of the Linux command line. It is not a complete guide to the command line, but rather an introduction to complement <phrase>Kubuntu</phrase>'s graphical tools.

<ulink url="http://linuxsurvival.com/index.php"/> - Java-based tutorials.

Deletes the entire current line

Deletes the word before the cursor

Executes the command selected

<emphasis role="strong">Command Line Linux is case sensitive.</emphasis> User, user, and USER are each different and distinct in Linux.

Introduction To The Command Line

Credits and License

This document is maintained by the Ubuntu documentation team (https://wiki.ubuntu.com/DocumentationTeam). For a list of contributors, see the <ulink url="help:/kubuntu/contributors.html">contributors page</ulink>

This document is made available under the Creative Commons ShareAlike 2.5 License (CC-BY-SA).

You are free to modify, extend, and improve the Ubuntu documentation source code under the terms of this license. All derivative works must be released under this license.

This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE AS DESCRIBED IN THE DISCLAIMER.

A copy of the license is available here: <ulink url="help:/kubuntu/copyright.html">Creative Commons ShareAlike License</ulink>.

Ubuntu Documentation Project

Canonical Ltd. and members of the <placeholder-1/>

The Ubuntu Documentation Project

Introduction

man intro(1)

The commands should be issued from a command prompt within a <application>Terminal</application> and will be shown as: <screen>command to type</screen>

Starting A Terminal

<phrase>Kubuntu</phrase>'s Terminal application is called <application>Konsole</application>, and is opened by going to <menuchoice><guimenu>Kickoff Application Launcher</guimenu><guisubmenu>Applications</guisubmenu><guisubmenu>System</guisubmenu><guimenuitem>Terminal (Konsole)</guimenuitem></menuchoice>.

<phrase>Kubuntu</phrase>'s terminal - Konsole

File and Directory Commands

pwd - print working directory