<sect1 id="howto-slaves">
<title>Playing from &kde; I/O Slaves</title>

<sect2 id="howto-slaves-about">
<title>What are &kde; I/O Slaves</title>

<para>&kde; has a great way to access all kinds of data through a system known
as <acronym>I/O</acronym> Slaves. They are little programs that let you
represent many different sources of data as <acronym>URL</acronym> like
addresses, and open them in &kde; programs like &konqueror; and &kplayer;. For
example you can access a network host over <acronym>SSH</acronym> with a
<acronym>URL</acronym> like <filename>fish:/host/path/</filename>, or a zip file
with <filename>zip:/home/cooldude/my.zip</filename>.</para>

</sect2>

<sect2 id="howto-slaves-using">
<title>How &kplayer; uses them</title>

<para>Many of the &kde; <acronym>I/O</acronym> Slaves can return video and audio
files and streams, for example <literal>fish:</literal>,
<literal>sftp:</literal>, <literal>webdav:</literal>, <literal>tar:</literal>,
<literal>zip:</literal>, <literal>audiocd:</literal> and so on. &kplayer; will
play them just like any other type of file. By default it will pass the data
directly to &mplayer; through a named pipe. If that does not work for any
reason, you can tell &kplayer; to use a temporary file for playing from &kde;
<acronym>I/O</acronym> Slaves on the <guilabel>Advanced</guilabel> page either
globally in <link linkend="settings-advanced">&kplayer; Settings</link> or in
individual <link linkend="properties-advanced">File Properties</link>. &kplayer;
will then download the entire file into a temporary directory before playing it,
which will consume some disk space temporarily, but will allow seeking and
length detection.</para>

<para>Note that with the <literal>audiocd</literal> slave you will probably have
to play the <literal>.wav</literal> files from the <guilabel>By Track</guilabel>
directory, since &mplayer; currently fails to play <literal>.cda</literal>
files. Or you can use a <link linkend="howto-devices"><literal>cdda:</literal>
<acronym>URL</acronym>s</link> instead.</para>

</sect2>

<sect2 id="howto-slaves-http">
<title>HTTP, FTP and Samba</title>

<para>The best way to play <acronym>URL</acronym>s that
<link linkend="howto-installation-mplayer">&mplayer;</link> supports is by
passing them on to &mplayer; directly. However, there will be cases where you
need to use &kplayer; support for playing from
<link linkend="howto-slaves">&kde; <acronym>I/O</acronym> Slaves</link> for
those types of <acronym>URL</acronym>s.</para>

<para>For example, the &mplayer; folks managed to release &mplayer; 1.0-pre4
with <acronym>FTP</acronym> support and handling of encodable characters in
<acronym>URL</acronym>s both broken all the way down. So if you use that
version, you will need to enable the use of <acronym>I/O</acronym> Slave for
<acronym>FTP</acronym> on the
<link linkend="settings-advanced">Advanced page</link> in
<guilabel>&kplayer; Settings</guilabel>, and if you need to play an
<acronym>HTTP</acronym> <acronym>URL</acronym> with a space in it for example,
you will need to turn on the <acronym>HTTP</acronym> <acronym>I/O</acronym>
Slave on the <guilabel>Advanced</guilabel> page either for that individual
<acronym>URL</acronym> in its <link linkend="properties-advanced">File
Properties</link>, or globally for all <acronym>HTTP</acronym>
<acronym>URL</acronym>s in <link linkend="settings-advanced">&kplayer;
Settings</link>.</para>

<para>Also, Samba support is still listed as experimental in &mplayer;,
so if it is not compiled into your &mplayer; or it is broken, go to the
<link linkend="settings-advanced">Advanced page</link> in
<guilabel>&kplayer; Settings</guilabel> and turn on the use of &kde;
<acronym>I/O</acronym> Slaves for <acronym>SMB</acronym>
<acronym>URL</acronym>s.</para>

</sect2>

<sect2 id="howto-slaves-cache">
<title>Cache size</title>

<para>When playing directly from a &kde; <acronym>I/O</acronym> Slave, the
<guilabel>Cache</guilabel> setting is important. It should not be too small so
&mplayer; can detect the encoding type without discarding data, but on the other
hand with large values it will take longer to fill the cache, especially with
low bitrate streams like <link linkend="howto-streams">online radio
stations</link>.</para>

<para>&kplayer; uses one megabyte of cache by default, but in many cases you can
go much lower than that, for example for most audio files 64 kilobytes is
enough. The cache size can be set on the <guilabel>Advanced</guilabel> page
either globally in <link linkend="settings-advanced">&kplayer; Settings</link>
or in individual <link linkend="properties-advanced">File Properties</link>.
Keep in mind that the global setting will also affect files played directly by
&mplayer;, and changing it can cause unwanted side effects. For example, cache
size lower than one megabyte has been found to cause <acronym>AVI</acronym>
files take a few seconds to start playing.</para>

</sect2>

<sect2 id="howto-slaves-playlists">
<title>Playlists</title>

<para>When using a &kde; <acronym>I/O</acronym> Slave to play a playlist file,
only the playlist file itself will be retrieved from the
<acronym>I/O</acronym> Slave. All the <acronym>URL</acronym>s it contains will
be played by &mplayer; directly. You have to give &kplayer; the
<acronym>URL</acronym> contained in the playlist if you want it to be played
through an <acronym>I/O</acronym> Slave.</para>

</sect2>

</sect1>