<chapter id="screensavers-0">
  <title>Setting Screensavers</title>
  <highlights>
    <para>This chapter describes how to set preferences for the screensaver.
This chapter also provides information on how to modify the displays that
are available for the screensaver.</para>
  </highlights>
  <sect1 id="screensavers-1">
    <title>Introduction to Screensavers</title>
    <indexterm>
      <primary>screensavers</primary>
      <secondary>introduction</secondary>
    </indexterm>
    <indexterm>
      <primary>XScreenSaver</primary>
      <see>screensavers</see>
    </indexterm>
    <para>A <firstterm>screensaver</firstterm> is an application that
replaces the image on a screen when the screen is not in use. The screensaver
application for the GNOME Desktop is <application>XScreenSaver</application>.
The following sections describe how to set preferences for the <application>XScreenSaver</application> application, and how to modify the displays that
are available for the screensaver.</para>
  </sect1>
  <sect1 id="screensavers-2">
    <title>Setting Screensaver Preferences</title>
    <indexterm>
      <primary>screensavers</primary>
      <secondary>setting preferences</secondary>
    </indexterm>
    <para>Default screensaver preferences are stored in a file that
is called <filename>XScreenSaver</filename>. This file is stored in <filename>/usr/X11R6/lib/X11/app-defaults/XScreenSaver</filename>.</para>
    <para>To modify screensaver application preferences, users can use the <application>Screensaver</application> preference tool. When a user modifies the screensaver
preferences, the preferences are stored in the home directory of the user,
in the <filename>$HOME/.xscreensaver</filename> file. For information on screensaver preferences, see <citetitle>GNOME 2.6 Desktop User Guide</citetitle>.</para>
    <para>Users can
also run the command <command>/usr/bin/xscreensaver-demo</command> to open
the <guilabel>XScreenSaver</guilabel> dialog.</para>
    <para>To set default screensaver preferences for all users, modify the <filename>XScreenSaver</filename> file. You can also use the <guilabel>XScreenSaver</guilabel> dialog to create a <filename>$HOME/.xscreensaver</filename> file,
then copy the file to the location of the <filename>XScreenSaver</filename>
file.</para>
    <para>To restore the default settings for a user, delete the <filename>$HOME/.xscreensaver</filename> file from the home directory of the user. If no <filename>$HOME/.xscreensaver</filename> file is present, the default preferences in the <filename>XScreenSaver</filename> file are used. </para>
    <note>
      <para>The default display behavior of <application>XScreenSaver</application>
is to display a blank screen. The blank screen might confuse users. You might
want to change this default display behavior.</para>
    </note>
    <para>To activate changes to the screensaver preferences, use the following
command to reload screensaver preferences:</para>
    <para>
      <computeroutput>#</computeroutput>
      <userinput>xscreensaver-command -restart</userinput>
    </para>
    <note>
      <para>The <application>xset</application> application does not work
with <application>XScreenSaver</application> at the time of publication of
this guide. To modify screensaver preferences, modify the <filename>XScreenSaver</filename> file or the <filename>$HOME/.xscreensaver</filename> file. </para>
    </note>
  </sect1>
  <sect1 id="screensavers-3">
    <title>Modifying Screensaver Displays</title>
    <indexterm>
      <primary>screensavers</primary>
      <secondary>modifying screensaver
displays</secondary>
    </indexterm>
    <para>The screensaver application allows users
to choose one or more <firstterm>screensaver displays</firstterm>. A screensaver
display is an application that displays images on the screen of the user when
the screen is not in use. The screensaver displays are listed in the <filename>XScreenSaver</filename> file and in the <filename>$HOME/.xscreensaver</filename>
file. </para>
    <para>To add a new
screensaver display, copy the executable file for the display to the directory
where the displays are located. Add the command for the screensaver display
to the <filename>XScreenSaver</filename> file or the <filename>$HOME/.xscreensaver</filename> file. Include any arguments that are required to run the screensaver
display on the whole screen, rather than in a window. For example, you might
want to include the <literal>-root</literal> option to display the screensaver
display on the whole screen.</para>
    <para>To disable a screensaver display, add
a minus sign (-) at the start of the command for the screensaver display in
the preferences file. The following excerpt from a <filename>$HOME/.xscreensaver</filename> file shows a disabled <literal>Qix (solid)</literal> screensaver
display:</para>
    <literallayout>-		 &quot;Qix (solid)&quot; 	qix -root -solid -segments 100</literallayout>
  </sect1>
</chapter>
