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diff --git a/doc/FAQ.html.in b/doc/FAQ.html.in deleted file mode 100644 index 9cacfb4c..00000000 --- a/doc/FAQ.html.in +++ /dev/null @@ -1,157 +0,0 @@ -<?xml version="1.0" encoding="iso-8859-1"?> <!-- -*-html-helper-*- --> -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml"> -<head> -<title>polypaudio: FAQ</title> -<link rel="stylesheet" type="text/css" href="style.css" /> -</head> - -<body> - - -<h1>Frequently Asked Questions</h1> - -<ol> - <li><p><b>How does Polypaudio compare with ESOUND/aRts/NAS?</b></p> - - <p>Polypaudio is sound daemon similar to ESOUND and NAS, but much more - powerful. aRts is a realtime-synthesizer-cum-sound-server, i.e. it - does much more than Polypaudio. However, I believe that Polypaudio - does what it does much better than any other free sound server.</p> - </li> - - <li><p><b>What about ESOUND compatibility?</b></p> - <p>Polypaudio is a drop in replacement for ESOUND. That means: you can - load a esound compatibility module which implements an ESOUND - compatible protocol which allows you to use most of the classic ESOUND - compatible programs (including the command line programs like - <tt>esdcat</tt>).</p> - </li> - - <li><p><b>Is Polypaudio a GNOME program?</b></p> - <p>No, Polypaudio has no dependency on GNOME/GTK/GLIB. All it requires - is a UNIX-like operating system and very few dependency - libraries. However, the accompanying GUI tools are writen with - gtkmm, i.e. require both GLIB and GTK.</p></li> - - <li><p><b>Can I integrate Polypaudio in my GLIB/GTK/GNOME application?</b></p> - <p>Yes! Polypaudio comes with a GLIB main loop adapter. You can embed - both the client library and the daemon (!) into your GLIB based - application.</p></li> - - <li><p><b>Can I integrate Polypaudio in my Qt/KDE application?</b></p> - <p>Yes! Polypaudio uses a main loop abstraction layer that allows you - to integrate Polypaudio in any program that supports main - loops. Unfortunately there is no adapter for Qt publicly available yet.</p></li> - - <li><p><b>I want to write a new driver for Polypaudio, are there any docs?</b></p> - <p>Currently, only the client API is documented with doxygen. Read - the source and base your work on a simple module like - <tt>module-pipe-sink</tt>.</p></li> - - <li><p><b>What about compatibility with NAS?</b></p> - <p>Is not available (yet?). It is doable, but noone has implemented it yet.</p></li> - - <li><p><b>What about compatibility with aRts?</b></p> - <p>Is not available. Since aRts is as synthesizer application you'd have to - reimplement very much code for Polypaudio. It should be easy to - implement limited support for <tt>libartsc</tt> based - applications. Noone has done this yet. It is probably a better idea to - run <tt>arts</tt> on top of Polypaudio (through a polypaudio driver - for aRts, which nobody has written yet). Another solution would be to - embed Polypaudio in the aRts process.</p></li> - - <li><p><b>I often hear noises when playing back with Polypaudio, what can I do?</b></p> - <p>There are to possible solutions: run polypaudio with argument -<tt>--high-priority=1</tt> and make yourself member of the group -<tt>realtime</tt>, or increase the fragment sizes of the audio - drivers. The former will allow Polypaudio to activate - <tt>SCHED_FIFO</tt> high priority scheduling (root rights are dropped - immediately after this) Keep in mind that this is a potential security hole!</p></li> - - <li><p><b>The <tt>polypaudio</tt> executable is installed SUID root by default. Why this? Isn't this a potential security hole?</b></p> - - <p>Polypaudio activates <tt>SCHED_FIFO</tt> scheduling if the user -passes <tt>--high-priority=1</tt>. This will only succeed when -executed as root, therefore the binary is marked SUID root by -default. Yes, this is a potential security hole. However, polypaudio -tries its best to minimize the security threat: immediately after -startup polypaudio drops all capabilities except -<tt>CAP_SYS_NICE</tt> (At least on systems that support it, like Linux; see <tt>man 7 -capabilities</tt> for more information). If the calling user is not a -member of the group <tt>realtime</tt> (which is required to have a GID -< 1000), root rights are dropped immediately. This means, you can -install polypaudio SUID root, but only a subset of your users (the -members of the group <tt>realtime</tt>) may make use of realtime -scheduling. Keep in mind that these users might load their own binary -modules into the polypaudio daemon which may freeze the machine. The -daemon has a minimal protection against CPU hogging (the daemon is -killed after hogging more than 70% CPU for 5 seconds), but this may -be circumvented easily by evildoers.</p></li> - - <li><p><b>I want to run polypaudio only when it is needed, how do I do this?</b></p> - - <p>Set <tt>autospawn = yes</tt> in <tt>client.conf</tt>. That -configuration file may be found either in <tt>/etc/polypaudio/</tt> or -in <tt>~/.polypaudio/</tt>.</p></li> - - <li><p><b>How do I list all polypaudio modules installed?</b></p> - - <p><tt>polypaudio --dump-modules</tt></p> - - <p>Add <tt>-v</tt> for terse usage instructions.</p> - -<li><p><b>How do I use polypaudio over the network?</b></p> - -<p>Just set <tt>$POLYP_SERVER</tt> to the host name of the polypaudio server.</p> - -<li><p><b>Is polypaudio capable of providing synchronized audio playback over the network for movie players like <tt>mplayer</tt>?</b></p> - -<p>Yes! Unless your network is congested in some way (i.e. transfer latencies vary strongly) it works perfectly. Drop me an email for experimental patches for MPlayer.</p> - - <li><p><b>What environment variables does polypaudio care about?</b></p> - -<p>The client honors: <tt>POLYP_SINK</tt> (default sink to connect to), <tt>POLYP_SOURCE</tt> (default source to connect to), <tt>POLYP_SERVER</tt> (default server to connect to, like <tt>ESPEAKER</tt>), <tt>POLYP_BINARY</tt> (the binary to start when autospawning a daemon), <tt>POLYP_CLIENTCONFIG</tt> (path to the client configuration file).</p> - -<p>The daemon honors: <tt>POLYP_SCRIPT</tt> (default CLI script file run after startup), <tt>POLYP_CONFIG</tt> (default daemon configuration file), <tt>POLYP_DLPATH</tt> (colon separated list of paths where to look for modules)</p></li> - - -<li><p><b>I saw that SIGUSR2 provokes loading of the module <tt>module-cli-protocol-unix</tt>. But how do I make use of that?</b></p> - -<p>A brilliant guy named Lennart Poettering once wrote a nifty tool -for that purpose: <a -href="http://0pointer.de/lennart/projects/bidilink/">bidilink</a>. To -connect to a running polypaudio daemon try using the following commands:</p> - -<pre>killall -USR2 polypaudio -bidilink unix-client:/tmp/polypaudio/cli</pre> - -<p><i>BTW: Someone should package that great tool for Debian!</i></p> - - -<p><b>New:</b> There's now a tool <tt>pacmd</tt> that automates sending SIGUSR2 to the daemon and running a bidilink like tool for you.</p> -</li> - -<li><p><b>How do the polypaudio libraries decide where to connect to?</b></p> -<p>The following rule applies:</p> -<ol> - <li>If the the application using the library specifies a server to connect to it is used. If the connection fails, the library fails too.</li> - <li>If the environment variable <tt>POLYP_SERVER</tt> is defined the library connects to that server. If the connection fails, the library fails too.</li> - <li>If <tt>$DISPLAY</tt> is set, the library tries to connect to that server and looks for the root window property <tt>POYLP_SERVER</tt> for the host to connect to. If <tt>POLYP_COOKIE</tt> is set it is used as authentication cookie.</li> - <li>If the client configuration file (<tt>~/.polypaudio/client.conf</tt> or <tt>/etc/polypaudio/client.conf</tt>) sets the server address, the library connects to that server. If the connection fails, the library fails too.</li> - <li>The library tries to connect to the default local UNIX socket for polypaudio servers. If the connection fails, it proceeds with the next item.</li> - <li>The library tries to connect to the default local TCP socket for polypaudio servers. If the connection fails, it proceeds with the next item.</li> - <li>If <tt>$DISPLAY</tt> is set, the library tries to connect to the default TCP port of that host. If the connection fails, it proceeds with the next item.</li> - <li>The connection fails.</li> -</ol> -</li> - -<li><p><b>Why the heck does libpolyp link against libX11?</b></p> -<p>The Polypaudio client libraries look for some X11 root window properties for the credentials of the Polypaudio server to access. You may compile Polypaudio without X11 for disabling this.</p></li> - -</ol> - -<hr/> -<address class="grey">Lennart Poettering <@PACKAGE_BUGREPORT@>, September 2004</address> -<div class="grey"><i>$Id$</i></div> -</body> </html> |