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<div class="document" id="using-systemd-service-management">
<h1 class="title">Using Systemd Service Management</h1>

<div class="contents topic" id="contents">
<p class="topic-title">Contents</p>
<ul class="simple">
<li><a class="reference internal" href="#initial-setup" id="toc-entry-1">Initial Setup</a></li>
<li><a class="reference internal" href="#managing-brltty-instances" id="toc-entry-2">Managing BRLTTY Instances</a><ul>
<li><a class="reference internal" href="#usb-braille-devices" id="toc-entry-3">USB Braille Devices</a></li>
<li><a class="reference internal" href="#the-default-instance" id="toc-entry-4">The Default Instance</a></li>
<li><a class="reference internal" href="#additional-instances" id="toc-entry-5">Additional Instances</a></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="initial-setup">
<h2><a class="toc-backref" href="#toc-entry-1">Initial Setup</a></h2>
<p>The following steps need to be performed:</p>
<ul class="simple">
<li>Systemd service and path units need to be installed
into the /usr/lib/systemd/system directory:<ul>
<li>brltty&#64;.service</li>
<li>brltty-device&#64;.service</li>
<li>brltty.path</li>
<li>brltty&#64;.path</li>
</ul>
</li>
<li>A wrapper script needs to be installed
into the /usr/libexec/brltty directory:<ul>
<li>systemd-wrapper</li>
</ul>
</li>
<li>A file defining the non-root user that BRLTTY is to run as,
including the supplementary groups that it needs access to,
needs to be installed into the /usr/lib/sysusers.d directory:<ul>
<li>sysusers -&gt; brltty.conf</li>
</ul>
</li>
<li>A file defining the files and directories that should exist
needs to be installed into the /usr/lib/tmpfiles.d directory:<ul>
<li>tmpfiles -&gt; brltty.conf</li>
</ul>
</li>
</ul>
<p>A make file has been provided in order to make this easy to do.
It can be found within the Autostart/Systemd subdirectory
of BRLTTY's build tree.
To install all of these files, change to this directory and run the command:</p>
<pre class="literal-block">
make install
</pre>
<p>You then need to tell Systemd that the files have been installed.
To do this, run the command:</p>
<pre class="literal-block">
systemctl daemon-reload
</pre>
<p>That's all you need to do.
Your system is now able to manage BRLTTY instances via Systemd.</p>
</div>
<div class="section" id="managing-brltty-instances">
<h2><a class="toc-backref" href="#toc-entry-2">Managing BRLTTY Instances</a></h2>
<p>Systemd manages BRLTTY instances on your system in a number of ways.</p>
<div class="section" id="usb-braille-devices">
<h3><a class="toc-backref" href="#toc-entry-3">USB Braille Devices</a></h3>
<p>If BRLTTY's Udev rules have also been installed
then a BRLTTY instance will be automatically started
when a USB braille device is connected,
and automatically stopped when it's disconnected.
Several braille devices can be managed in this way at the same time.
They can be connected and disconnected at any time and in any order.</p>
<p>The default configuration file - <tt class="docutils literal">/etc/brltty.conf</tt> - is used
except that any <tt class="docutils literal"><span class="pre">braille-device</span></tt> and <tt class="docutils literal"><span class="pre">braille-driver</span></tt> directives
that it specifies are ignored because they're overridden by the Udev rules.
It's safe, therefore, to specify a default non-USB braille device
within <tt class="docutils literal">/etc/brltty.conf</tt>.</p>
</div>
<div class="section" id="the-default-instance">
<h3><a class="toc-backref" href="#toc-entry-4">The Default Instance</a></h3>
<p>The default BRLTTY instance is the one that's configured
via the file <tt class="docutils literal">/etc/brltty.conf</tt>.
It's managed by applying standard Systemd commands to BRLTTY's path unit.
For example:</p>
<pre class="literal-block">
systemctl enable brltty.path
systemctl start brltty.path
systemctl stop brltty.path
systemctl disable brltty.path
</pre>
</div>
<div class="section" id="additional-instances">
<h3><a class="toc-backref" href="#toc-entry-5">Additional Instances</a></h3>
<p>Additional BRLTTY instances can be managed via path instance references.
Each of them has its own configuration file.</p>
<p>If, for example, the name of an instance is <tt class="docutils literal">iname</tt>, then
its Systemd path name would be <tt class="docutils literal">brltty&#64;iname</tt>,
its configuration file would be <tt class="docutils literal">/etc/brltty_iname.conf</tt>,
and it'd be managed via Systemd commands like these:</p>
<pre class="literal-block">
systemctl enable brltty&#64;iname.path
systemctl start brltty&#64;iname.path
systemctl stop brltty&#64;iname.path
systemctl disable brltty&#64;iname.path
</pre>
<p>Any number of instances may be managed in this way.
These instances don't implicitly also read the default configuration file
(<tt class="docutils literal">/etc/brltty.conf</tt>).
You can, however, explicitly include it
from within any instance-specific configuration file:</p>
<pre class="literal-block">
include <tt class="docutils literal">/etc/brltty.conf</tt>
</pre>
</div>
</div>
</div>
</body>
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