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<a name="top">
<left>
<p><h6>
Back to <a href="documentation.html">documentation</a>
</h6></p>
<p><h6>
2000 December 1
</h6></p>

</left>
<center>
<h1>YIFF Sound Server<br>Configuration HOWTO</h1>
</center>

<left>
<h3>Contents</h3>
<ol>
 <li><a href="#s1">Basics about sound on computers</a>
 <li><a href="#s2">Y Sound System terminology</a>
 <li><a href="#s3">Requirements</a>
 <li><a href="#s4">Setting up <code>yiffrc</code></a>
 <li><a href="#s5">`Walk-though' using the Y Sound Server</a>
 <li><a href="#s6">Y server run on demand rules</a>
</ol>
</left>



<left>
<img src="hr1.gif" width=95% height=32>
<a name="s1">
<h2>Basics about sound on computers</h2>
<p>
Knowing the fundimentals on how your computer produces sound is the most
important topic of configuring the YIFF Sound Server, newbies and
advanced gurus should take a moment to review this section
<u>throughly</u>!
</p>

<p>
Your computer produces (and records) sound using an <i>audio adapter</i>,
more commonly reffered to as a <i>sound card</i>. The Y Sound System
reffers to this as the <i>recorder</i> (details in the
<a href="#s2">next section</a>). We will reffer to it as the
<i>sound card</i> for now...
</p>

<p>
The sound card has the following configurable attributes (some sound
cards may have additional attributes and features):
<ul>
 <li><i>Digital Sound Processor</i> (abbriviated DSP), this is the part
of the sound card that produces per sample sound.
 <li><i>Musical instrument data interface synth</i> (abbriviated MIDI),
this is the part of the sound card that produces preprogrammed musical
instrument sounds from a given sequence of notes to play (not all
sound cards have this).
 <li><i>Sample rate</i> the speed at which each <i>sample</i> is played.
This unit is measured in Hz on the DSP.
 <li><i>Sample size</i> the number of bits (usually 8 or 16) representing
one sample on the DSP.
 <li><i>Channels</i> the number of channels; 1 for mono, 2 for stereo,
and 4 for quad. Note that quad sound is not supported on all systems.
 <li><i>Buffer fragment size</i> the number of bytes being played per
<i>cycle</i> on the DSP.
</ul>
</p>

<p>It is critical that you know how to calculate the above
information when configuring the YIFF Sound Server (and using Y
client applications too).
</p>

<p>
YIFF and the Y system handles data in bytes, for instance if you
set the sample rate to 11025 Hz and the sample size was set to 8 bits
with 1 channel then you would have 11025 * 1 * 1 = 11025 bytes per
second. Since
there are 8 bits in one byte, but what if the sample size was 16 bits?
Then that would be two bytes per sample. So now you would have
11025 * 2 * 1 = 22050 bytes per second.
</p>

<p>
In the above two examples the number of channels remained at a constant
1. What if you had a sample rate of 11025 Hz and sample size was set to
8 bits but channels is set to 2? Although each sample is represented by
one byte, you have two channels therefore it is one sample per
channel. So with two channels you would have a total of 11025 *
1 * 2 = 22050 bytes
per second even though the sample size is set to 8 bits (one byte).
</p>

<p>Lastly if the sample rate was 22050 Hz and the sample size was set
to 16 bits (2 bytes) and channels set to 2. Then you would have
22050 * 2 * 2 = 88200 bytes.
</p>

<p>Now we add one more attribute in to the equation and that is
<i>buffer fragment size</i>. The sound card driver does not handle
updates in seconds, rather it updates things in <i>cycles</i>. A
<i>cycle</i> can have a variable relationship with real time,
it is determined by the other attributes <i>sample rate</i>,
<i>sample size</i>, <i>channels</i>, and <i>buffer fragment size</i>.
</p>

<p>Software under most circumstances calculates the cycle, however
YIFF allows you to either let it calculate it or allow you to
set an explicit value for a set of conditions. The cycle is usually
measured in <i>microseconds</i> (abbriviated <i>us</i>), and is calculated
with the following equation:
<ul>
 <li><code>cycle_us = 1,000,000 / (sample_rate * channels *
(sample_size_bits / 8)) * buffer_fragment_size / 1.5</code>
</ul>
That equation calculates the cycle for a typical double buffer
(two buffer fragments) situation. Assuming <code>sample_rate</code> and
<code>channels</code> are greater than 0 and <code>sample_size_bits</code>
is greater than or equal to 8. <code>buffer_fragment_size</code>
is a 2^n value (ie 256, 512, 1024, etc...).
Note that this equation conforms to the
<a href="http://www.opensound.com/">Open Sound System
(OSS) implmentation</a>.
</p>

<p>If the <i>cycle</i> interval is too big then you will here rapit
`clicks' or `gaps' in the sound, if it is set too small then the buffers
will slowly overflow. Note that YIFF will try its best to keep the buffer
from overflowing by resyncing the sound driver every few seconds
(you can adjust this interval too). So it's generally safer to make the
cycle interval value a tad smaller at a cost to performance. However
in most situations the calculated theoretical cycle interval will work
just fine.
</p>

<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>



<left>
<img src="hr1.gif" width=95% height=32>
<a name="s2">
<h2>Y Sound System terminology</h2>
<p>
The Y Sound System employs a few additional terms to generalize
additional conceptual properties about using your sound card.
These conceptual properties will help make it easier to work with
sound using the Y system at a higher level.
<ul>
 <li><i>Recorder</i> addresses the entire audio device or sound card unit. 
 <li><i>Audio</i> is a set of adjustable parameters for a recorder.
 <li><i>Sound</i> the segment of data representing sound currently being
played or recorded.
 <li><i>Cycle</i> is the interval in which the <i>Sound</i> is updated to
the <i>recorder</i>.
</ul>
</p>

<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>


<left>
<img src="hr1.gif" width=95% height=32>
<a name="s3">
<h2>Requirements</h2>
<p>
<ol>
 <li>A system with any of the following drivers installed:
  <ul>
   <li><a href="http://www.alsa-project.org/">
Advanced Linux Sound Architechture (ALSA)</a>
   <li>Linux sound driver (plain vanilla driver from the kernel)
   <li><a href="http://www.opensound.com/">
Open Sound System (OSS)</a>
  </ul>
 <li>Latest <a href="download.html">YIFF Sound Server</a>
 installed (but not configured)
</ol>
</p>

<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>



<left>
<img src="hr1.gif" width=95% height=32>
<a name="s4">
<h2>Setting up <code>yiffrc</code></h2>
<p>
The <code>yiffrc</code> is a configuration file which the YIFF
Sound Server needs in order to run properly, this file is usually
placed in <code>/usr/etc/yiffrc</code>.
</p>

<p>A default copy is placed in <code>/usr/etc/yiffrc</code> when
you first install the YIFF Sound Server. There are two ways to
edit this file, you can edit it by hand or use <code>yiffconfig</code>
</p>

<p>
You are strongly encuraged to use <code>yiffconfig</code> first,
come back to this section of the HOWTO if and only if it does not work
and you need to configure it manually.
</p>

<p>
To configure <code>yiffrc</code> manually, run your prefered text editor
and read through the entire configuration file first. Each section and
parameter should come fully commented (a comment is a line starting
with a <code>#</code> character).  Read each comment carefully and
set the appropriate value. Some more important or obscure parameters
will be described as follows
</p>

<h4>Preset Y Audio Modes</h4>
<p>Preset <i>Y Audio Modes</i> are located in a section of configuration
blocks starting with <code>BeginYAudioMode</code> and ending with
<code>EndYAudioMode</code>. Reffer to the
<a href="#s1">basic properties of sound cards</a> to set the appropriate 
values, note that you should only change these values if they do not work
out at first (ie if you experience delays or 'clicks' during playing of
sound). Preset Y Audio Modes make it easier for Y clients to change
the Audio parameters by using preset ones which it would consider
as `known working Audio parameters'.
</p>

<p>Below is a sample section for Y Audio Modes:</p>
<p>
<pre><code>
BeginYAudioMode
    Name = Default
    Cycle = 30959
    WriteAhead = 46438
    SampleSize = 8
    Channels = 1
    SampleRate = 11025
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 512
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode
    Name = PlayMono8000
    Cycle = 42666
    WriteAhead = 63999
    SampleSize = 8
    Channels = 1
    SampleRate = 8000
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 512
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode   
    Name = PlayStereo8000
    Cycle = 42666
    WriteAhead = 63999
    SampleSize = 8
    Channels = 2
    SampleRate = 8000
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 1024
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode   
    Name = PlayMono11025
    Cycle = 30959
    WriteAhead = 46438
    SampleSize = 8
    Channels = 1
    SampleRate = 11025
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 512
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode   
    Name = PlayStereo11025
    Cycle = 30959
    WriteAhead = 46438
    SampleSize = 8
    Channels = 2
    SampleRate = 11025
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 1024
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode   
    Name = PlayMono22050
    Cycle = 30959
    WriteAhead = 46438
    SampleSize = 8
    Channels = 1
    SampleRate = 22050
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 1024
    FlipStereo = no
    Direction = Play
EndYAudioMode

BeginYAudioMode   
    Name = PlayStereo22050
    Cycle = 30959
    WriteAhead = 46438
    SampleSize = 8
    Channels = 2
    SampleRate = 22050
    AllowFragmenting = yes
    Fragments = 2
    FragmentSize = 2048
    FlipStereo = no
    Direction = Play
EndYAudioMode
</code></pre></p>

<p>That was just a sample of a few basic Y Audio Modes, note that
the names of the Y Audio Modes are important. You should have all
the standardized modes defined, reffer to the default <code>yiffrc</code>
that was installed with the rest of the YIFF Sound System for
a complete listing.
</p>

<p>
Note that <code>AllowFragmenting</code> should always be <code>yes</code> 
(it's backwards compatability for older versions of Linux). The number of
fragments <code>Fragments</code> should be <code>2</code> (for double
buffering).
</p>

<h4>MIDI Player Command</h4>
<p>
MIDI support requires an external player, there is a parameter called
<code>MIDIPlayCommand</code> it specifies the command to have YIFF
run when a Y client program requests that a MIDI type sound object
needs to be played. 
</p>

<p>
Example command if your player was <code>pmidi</code>:
</p>
<p><pre><code>
MIDIPlayCommand = /usr/bin/pmidi -p 65:0 %f
</code></pre></p>

<p>
Note that the <code>%f</code> will be replaced with the full path to
the sound object.
</p>

<p>Another related parameter is <code>MIDIDevicePort</code>, this value
is the ALSA MIDI device port number. This value is only used if
you are using ALSA, typically you can leave this value as <code>0</code>.
</p>


<h4>Y Sound Paths</h4>

<p>You can define one or more search paths called <i>Y Sound Paths</i>
which are directories to look for Sound object files (.wav or .mid files
for example). When a Y client gives a relative path to the YIFF server,
the YIFF server will search through each one of these paths for the
sound object looking for a match.
The Y Sound Paths configuration block begins with a
<code>BeginYSoundPath</code> and ends with a <code>EndYSoundPath</code>.
The search goes through the listing from first Y Sound Path defined to
the last one.
</p>

<p>For example</p>
<p><pre><code>
BeginYSoundPath
    Path = /usr/share/sounds
EndYSoundPath

BeginYSoundPath
    Path = /tmp
EndYSoundPath
</code></pre></p>

<p>
This covers most of the problem areas that might cause confusion during
configuring.</p>
<p>
If you are still having trouble configuring or have additional
questions about configuration, feel free to ask the
<a href="http://wolfpack.twu.net/contacts.html">authors</a>.
</p>

<p>To test if everything is working, make sure your sound drivers
are loaded and run:
<ul>
 <li><code>/usr/sbin/yiff /usr/etc/yiffrc</code>
</ul>
Be sure to read the <a href="#s5">next section</a> which shows you how to
run the YIFF Sound Server and modify it with the Y utility programs at run
time. ...Plus many other features!
</p>

<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>


<left>
<img src="hr1.gif" width=95% height=32>
<a name="s5">
<h2>`Walk-though' using the Y Sound Server</h2>
<p>Now hopefully you have atleast one working preset Y Audio Mode and
are ready to hear it work.
</p>

<h4>Starting the YIFF Sound Server</h4>
<p>
You can start the YIFF Sound Server as the user with the lowest
permissions, YIFF only needs access to the devices and locations
specified in the <code>yiffrc</code> configuration file.
</p>
<p>To start the YIFF Sound Server, just type (modify paths as needed):
<ul><li><code>
/usr/sbin/yiff /usr/etc/yiffrc
</code></ul>
The above command should have started
the YIFF Sound Server and print any warnings or errors encountered.
Some typical errors you might encounter are:
<ul>
 <li><code>/usr/etc/yiffrc: No such file.</code> This means that the
path to the configuration file is incorrect. Please specify the correct
path to the configuration file and make sure that
<code>/usr/sbin/yiff</code> has permission to check for its existance and
open it.
 <li>Cannot bind network listening port. The port number that
<code>/usr/sbin/yiff</code> listens to for incoming Y client connections
(default number is 9433) is already in user by another server or is not
allowed to be binded with the current permissions on
<code>/usr/sbin/yiff</code>. You may need to increase the permissions on
<code>/usr/sbin/yiff</code> or reduce the permissions on (give access
to) the network port number in question.
 <li><code>/dev/dsp: Cannot open for playing.</code> This may indicate
another non-Y compliant sound application is already trying to use the
digital sound processor device, check if any other programs are currently
running (type <code>ps aux</code>) that might be using
<code>/dev/dsp</code>. Also check if the sound driver is installed and
loaded properly (type <code>modprobe sound</code>).
</ul>
</p>

<p>
Note that the YIFF Sound Server will automatically run in the background,
if however you want to run YIFF in the foreground then add
<code>--foreground</code> to the command, for example:
<ul><li><code>
/usr/sbin/yiff /usr/etc/yiffrc --foreground
</code></ul>
To get a list of command line arguments for YIFF, type:
<ul><li><code>
/usr/sbin/yiff --help
</code></ul>
You can type the above regardless if YIFF running or not.
</p>
<p>
To formally start YIFF you should run:
<ul><li><code>
/usr/sbin/starty
</code></ul>
This is a script file that calls YIFF and sets up additional resources
(such as <i>yhosts</i>). You are responsible for writing this script
file, but note if you configured YIFF using <code>yiffconfig</code>
you should have been given an option to allow <code>yiffconfig</code>
to create a <code>/usr/sbin/starty</code> start script for you.
</p>

<h4>Is the YIFF Sound Server running?</h4>
<p>
There are two ways to check that:
<ol>
 <li><code>ps aux|grep yiff</code>
 <li><code>yrecinfo</code>
</ol>
The first command will basically check the complete list of processes
and show you the line (if any) for the pid of the YIFF Sound Server.
The second line is a more Y specific way of checking,
<code>yrecinfo</code> will print the status of the YIFF Sound Server
if it was able to connect to it or an error message if it was not able
to connect. A typical successful output from <code>yrecinfo</code>
would look like:
</p>
<p><pre><code>
recorder: 127.0.0.1:9433
version: 2.11
cycle load: 3.4%
maximum protocol statement: 30000 bytes
cycle set: 2
cycle: 30959 microseconds
compensated cycle: 30959 microseconds
write ahead: 46438 microseconds
cumulative latency: 0 microseconds
sample rate: 11025 Hz
channels: 1
sample size: 8 bits
bytes per second: 11025 bytes
allow sound buffer fragments: yes
sound buffer fragments: 2
sound buffer size: 512 bytes
flip stereo: no
direction: 0
</code></pre></p>

<p>
By default <code>yrecinfo</code> connects to port 9433 on the
computer it is running on, to specify an particular address and port,
type:
<ul><li><code>
yrecinfo --recorder 127.0.0.1:9433
</code></ul>
The above is the same as running <code>yrecinfo</code> without any
arguments but as you can see, you can get a different address by simply
changing <code>127.0.0.1</code> to a different address.
For a different port just change <code>9433</code> to the port number
you want. You should note that all Y compliant applications will handle
the <code>--recorder &lt;address&gt;:&lt;port&gt;</code> argument.
As always to get a full list of arguments available, run with the
argument <code>--help</code>, for example:
<ul><li><code>
yrecinfo --help
</code></ul>
</p>

<h4>Playing something</h4>
<p>If everything looks good so far, then its time to check if the YIFF
Sound Server can play something. Select a reasonably lengthed (1 MB or so)
wav, voc, or raw sound file and type:
<ul><li><code>
yplay -v -m /home/me/mysound.wav
</code></ul>
Replace <code>/home/me/mysound.wav</code> with the <u>full path</u> to
the sound file in question. Remember that if you pass a relative path,
the file will be searched through the Y Sound Paths list and if it is
not found <code>yplay</code> will return stating an error (the current
working directory is not checked). The <code>-v</code> and <code>-m</code>
arguments specify verbose and automatically change Audio values as needed
(respectivly). Typically the <code>-m</code> argument is discuraged
because changing the Audio mode as needed will cause any other Y client
application's sound objects to be killed. You can press
<code>ctrl+c</code> at any time during <code>yplay</code>'s playback
to stop it.
</p>
<p>
Next try and see if you can play a MIDI sound object, it's the same
procedure with <code>yplay</code> except that you tell it to play a midi 
file, for example:
<ul><li><code>
yplay -v -m /home/me/mysound.mid
</code></ul>
This might produce an error if your MIDI player program is not set up
properly. Run <code>yiffconfig</code> or edit <code>/usr/etc/yiffrc</code>
to change the <code>MIDIPlayCommand</code> parameter as needed.
</p>

<h4>Changing the Y Audio Mode manually</h4>
<p>
You can easilly switch preset Y Audio Modes or set specific Audio modes
using <code>yset</code>. This is a very powerful command, as it allows
you to manipulate many aspects of the YIFF Sound Server at run time.
For example, to switch preset Y Audio Modes first type:
<ul><li><code>
yrecinfo --modes
</code></ul>
This will print the YIFF Sound server status and a list of available Y Audio
Modes. Make note of a particular Y Audio Mode name you like to switch to
and type:
<ul><li><code>
yset audio PlayStereo11025
</code></ul>
Replace <code>PlayStereo11025</code> with the Y Audio Mode you want to
switch to (make sure it appeared in the <code>yrecinfo</code> list).
You may hear a 'click' as the Audio values are updated.
</p>
<p>
There are many options to <code>yset</code>, again to get a list of
arguments type:
<ul><li><code>
yset --help
</code></ul>
</p>

<h4>Shell out</h4>
<p>
One additional feature that should be pointed out at this time is that the
YIFF Sound
Server can <i>shell out</i>, what this means is that the YIFF Sound Server
will continue to; run normally, handle Y client connections, and play
sound... or so it seems. What its really doing is everything except play
sound. It will still communicate with the Y client programs connected to
it and 'lie' to them when they request to play a sound (it will
pretend its playing the sound but not actually play it). This is similar
in principal as a GUI switching to full screen mode to allow a non-GUI
program to run (old MS-Windows users should know what we mean here).
So basically YIFF will stop using the digital sound processor device
specified by the configuration parameter <code>DSPDevice</code> so other
non-Y applications can use it. So to shell out type:
<ul><li><code>
yset shellout
</code></ul>
You should get a message indicating the Y server has been shelled out, now
type:
<ul><li><code>
yplay -v /home/me/mysound.wav
</code></ul>
Do <b>not</b> specify the <code>-m</code> argument above (you'll see why
in a moment). When you press enter you will see that it appears the sound
is playing normally but you will hear nothing comming from the speakers.
Now press <code>ctrl+c</code> and type:
<ul><li><code>
yset audio default
</code></ul>
Any preset Y Audio Mode or Audio values will do, this will unshell and
bring YIFF back to running normally (make sure no other non-Y applications
are ysing the digital sound processor device when you type this). To
conferm that sound is back, type:
<ul><li><code>
yplay -v /home/me/mysound.wav
</code></ul>
Note that if you had specified <code>-m</code> to <code>yplay</code>, it
would have changed the Audio and thus unshell.
</p>

<h4>Mixers</h4>
<p>One thing that <code>yset</code> cannot manipulate are the Y mixers.
This is where a new command called <code>ymixer</code> is used, note that
not all sound cards have mixers and if even so not all mixer channels
exist (maybe not even <code>vol</code>, so double check your sound card
manual first before continuing on in this section).
</p>
<p>First to get a list of all Y mixers, just type:
<ul><li><code>
ymixer
</code></ul>
You should get a list of mixer channel names and their respective values
in percent.
</p>
<p>
To set a specific Y mixer value type:
<ul><li><code>
ymixer vol 70 40
</code></ul>
This will set the mixer <code>vol</code> to left channel 70 percent
and right channel 40 percent. To verify type:
<ul><li><code>
ymixer vol
</code></ul>
You may notice a slight different in output value as the YIFF server
adjusts to the internal values.
</p>
<p>
Note that the mixer device is specified in the
<code>yiffrc</code> configuration file by the parameter
<code>MixerDevice</code>. You can set this parameter's value to nothing
to indicate you have no mixer.
</p>
<p>
Your Y mixer settings are stored in a file in your home directory
called <code>.YMixerSettings</code> this file is automatically loaded
when you run the YIFF Sound Server and rewritten when you shut down the
YIFF Sound Server.
</p>

<h4>Allowing foreign Y clients</h4>
<p>Since Y Sound Systems is a network transparent system, it allows
Y clients from other computers to connect to the Y server, but not unless
you say so.
</p><p>
To allow a Y client on another computer to connect to a YIFF Sound Server
currently running on your computer type (on your comptuer):
<ul><li><code>
yhost wolfpack.twu.net
</code></ul>
This will add the host <code>wolfpack.twu.net</code> IP address to the
list of foreign yhosts (ip addresses) allowed to connect to the YIFF
Sound Server on your computer. Note that its better to specify an IP
address as it is more precise in security, for example:
<ul><li><code>
yhost 123.45.67.89
</code></ul>
To remove an address type:
<ul><li><code>
yhost - 123.45.67.89
</code></ul>
Note the <code>-</code> character which specifies to remove the address
from the allowed list of addresses.
</p>

<p>
Remember that changes you make using <code>yhost</code> are not
permanent, they will be gone once you shut down your YIFF Sound Server. So
to preserve changes you should add the <code>yhost</code> to your
<code>starty</code> script.
</p>

<p><font color=ff0000> Beware, allowing programs from other computers to
control YIFF will allow them to do bad things, such as shutting down YIFF
or having it play a million sound objects at once. <b>Only</b> specify
<code>yhost</code> addresses of computers <u>you trust</u>! </font></p>

<h4>Shutting down the YIFF Sound Server</h4>
<p>To shut down the YIFF Sound Server type:
<ul><li><code>
yshutdown
</code></ul>
This will have YIFF stop all sound objects being played, destroy all sound
objects, close connections to any Y client applications
currently connected and then shut down.
</p>

<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>


<left>
<img src="hr1.gif" width=95% height=32>
<a name="s6">
<h2>Y server run on demand rules</h2>
<p>
These are the rules for the conditions in when the YIFF Sound 
Server is started and shutdown (automatically) by Y client programs: 
<ol>
 <li>If a program wants to connect to the YIFF server, first that program
attempts a connect, if it is unable to connect then it attempts to start
the YIFF server (and makes note that it started YIFF) and attempts to
connect again.
 <li>If a program is currently connected to YIFF and wants to disconnect,
first it recalls if it started YIFF, if it did, it will shutdown YIFF,
otherwise it will just disconnect from YIFF.
</ol>
Remember, you can always shut down the Y server at any time using
<code>yshutdown</code>.
</p>

<p>You can also send a 
<code>kill -s INT &lt;pid&gt;</code> to the YIFF Sound Server, it will
recieve that signal and shutdown normally.
</p>

<p>
YIFF also responds to the HUP signal, type
<code>kill -s HUP &lt;pid&gt;</code>
YIFF reload its configuration and reset its resources. Warning,
this may disconnect any Y client programs currently connected.
</p>


<h4>Where to go from here?</h4>
<p>
Once you have everything set up you may want to take a look at the
<a href="links.html">links</a> to other neat and wonderful Y applications.
</p>


<h6>
Back to the <a href="#top">top</a>.
</h6>
</left>


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