Browsing French translation

74.

The default behavior for a command may usually be modified by adding <command>--option</command> to the command. For example, the <link linkend="ls"><command>ls</command></link> command has an <command>-s</command> option. The <command>ls -s</command> will include file sizes in the listing. There is also a <command>-h</command> option to display file sizes in a <quote>human readable</quote> format.

75.

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>

76.

<quote>Man</quote> and Getting Help

77.

<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.

78.

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.

79.

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.

80.

Move up and down the man file with the arrow keys, and quit back to the command prompt with <keycap>q</keycap>.

81.

<screen>man man</screen> brings up the manual entry for the <command>man</command> command, which is a good place to start.

82.

<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.

83.

There are also <command>info</command> pages, which generally go into more detail than <command>man</command> pages. Try: <screen>info info</screen> for the introduction to info pages.