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<li class="toctree-l2 current"><a class="current reference internal" href="#">Barrier client protocol</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#message-format">Message format</a></li>
<li class="toctree-l3"><a class="reference internal" href="#protocol-description">Protocol Description</a><ul>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdhello-barrier">barrierCmdHello  “Barrier”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdhelloback-barrier">barrierCmdHelloBack  “Barrier”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddinfo-dinf">barrierCmdDInfo  “DINF”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcnoop-cnop">barrierCmdCNoop  “CNOP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcclose-cbye">barrierCmdCClose “CBYE”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcenter-cinn">barrierCmdCEnter “CINN”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcleave-cout">barrierCmdCLeave “COUT”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcclipboard-cclp">barrierCmdCClipboard “CCLP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcscreensaver-csec">barrierCmdCScreenSaver   “CSEC”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcresetoptions-crop">barrierCmdCResetOptions  “CROP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdcinfoack-ciak">barrierCmdCInfoAck   “CIAK”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdckeepalive-calv">barrierCmdCKeepAlive “CALV”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddkeydown-dkdn">barrierCmdDKeyDown   “DKDN”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddkeyrepeat-dkrp">barrierCmdDKeyRepeat “DKRP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddkeyup-dkup">barrierCmdDKeyUp “DKUP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddmousedown-dmdn">barrierCmdDMouseDown “DMDN”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddmouseup-dmup">barrierCmdDMouseUp   “DMUP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddmousemove-dmmv">barrierCmdDMouseMove “DMMV”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddmouserelmove-dmrm">barrierCmdDMouseRelMove  “DMRM”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddmousewheel-dmwm">barrierCmdDMouseWheel “DMWM”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddclipboard-dclp">barrierCmdDClipboard “DCLP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddsetoptions-dsop">barrierCmdDSetOptions “DSOP”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmddfiletransfer-dftr">barrierCmdDFileTransfer “DFTR”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdddraginfo-ddrg">barrierCmdDDragInfo  “DDRG”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdqinfo-qinf">barrierCmdQInfo  “QINF”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdeincompatible-eicv">barrierCmdEIncompatible  “EICV”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdebusy-ebsy">barrierCmdEBusy  “EBSY”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdeunknown-eunk">barrierCmdEUnknown   “EUNK”</a></li>
<li class="toctree-l4"><a class="reference internal" href="#barriercmdebad-ebad">barrierCmdEBad   “EBAD”</a></li>
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  <div class="section" id="barrier-client-protocol">
<h1>Barrier client protocol<a class="headerlink" href="#barrier-client-protocol" title="Permalink to this headline">¶</a></h1>
<p>QEMU’s <code class="docutils literal notranslate"><span class="pre">input-barrier</span></code> device implements the client end of
the KVM (Keyboard-Video-Mouse) software
<a class="reference external" href="https://github.com/debauchee/barrier">Barrier</a>.</p>
<p>This document briefly describes the protocol as we implement it.</p>
<div class="section" id="message-format">
<h2>Message format<a class="headerlink" href="#message-format" title="Permalink to this headline">¶</a></h2>
<p>Message format between the server and client is in two parts:</p>
<ol class="arabic simple">
<li>the payload length, a 32bit integer in network endianness</li>
<li>the payload</li>
</ol>
<p>The payload starts with a 4byte string (without NUL) which is the
command. The first command between the server and the client
is the only command not encoded on 4 bytes (“Barrier”).
The remaining part of the payload is decoded according to the command.</p>
</div>
<div class="section" id="protocol-description">
<h2>Protocol Description<a class="headerlink" href="#protocol-description" title="Permalink to this headline">¶</a></h2>
<p>This comes from <code class="docutils literal notranslate"><span class="pre">barrier/src/lib/barrier/protocol_types.h</span></code>.</p>
<div class="section" id="barriercmdhello-barrier">
<h3>barrierCmdHello  “Barrier”<a class="headerlink" href="#barriercmdhello-barrier" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">minor,</span> <span class="pre">int16_t</span> <span class="pre">major</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Say hello to client</p>
<p><code class="docutils literal notranslate"><span class="pre">minor</span></code> = protocol major version number supported by server</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">major</span></code> = protocol minor version number supported by server</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdhelloback-barrier">
<h3>barrierCmdHelloBack  “Barrier”<a class="headerlink" href="#barriercmdhelloback-barrier" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>client -&gt;server</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">minor,</span> <span class="pre">int16_t</span> <span class="pre">major,</span> <span class="pre">char</span> <span class="pre">*name}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Respond to hello from server</p>
<p><code class="docutils literal notranslate"><span class="pre">minor</span></code> = protocol major version number supported by client</p>
<p><code class="docutils literal notranslate"><span class="pre">major</span></code> = protocol minor version number supported by client</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">name</span></code>  = client name</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddinfo-dinf">
<h3>barrierCmdDInfo  “DINF”<a class="headerlink" href="#barriercmddinfo-dinf" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>client -&gt;server</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">x_origin,</span> <span class="pre">int16_t</span> <span class="pre">y_origin,</span> <span class="pre">int16_t</span> <span class="pre">width,</span> <span class="pre">int16_t</span> <span class="pre">height,</span> <span class="pre">int16_t</span> <span class="pre">x,</span> <span class="pre">int16_t</span> <span class="pre">y}</span></code></dd>
<dt>Description:</dt>
<dd>The client screen must send this message in response to the
barrierCmdQInfo message.  It must also send this message when the
screen’s resolution changes.  In this case, the client screen should
ignore any barrierCmdDMouseMove messages until it receives a
barrierCmdCInfoAck in order to prevent attempts to move the mouse off
the new screen area.</dd>
</dl>
</div>
<div class="section" id="barriercmdcnoop-cnop">
<h3>barrierCmdCNoop  “CNOP”<a class="headerlink" href="#barriercmdcnoop-cnop" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>client -&gt; server</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>No operation</dd>
</dl>
</div>
<div class="section" id="barriercmdcclose-cbye">
<h3>barrierCmdCClose “CBYE”<a class="headerlink" href="#barriercmdcclose-cbye" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Close connection</dd>
</dl>
</div>
<div class="section" id="barriercmdcenter-cinn">
<h3>barrierCmdCEnter “CINN”<a class="headerlink" href="#barriercmdcenter-cinn" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">x,</span> <span class="pre">int16_t</span> <span class="pre">y,</span> <span class="pre">int32_t</span> <span class="pre">seq,</span> <span class="pre">int16_t</span> <span class="pre">modifier</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Enter screen.</p>
<p><code class="docutils literal notranslate"><span class="pre">x</span></code>, <code class="docutils literal notranslate"><span class="pre">y</span></code>  = entering screen absolute coordinates</p>
<p><code class="docutils literal notranslate"><span class="pre">seq</span></code>  = sequence number, which is used to order messages between
screens.  the secondary screen must return this number
with some messages</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">modifier</span></code> = modifier key mask.  this will have bits set for each
toggle modifier key that is activated on entry to the
screen.  the secondary screen should adjust its toggle
modifiers to reflect that state.</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdcleave-cout">
<h3>barrierCmdCLeave “COUT”<a class="headerlink" href="#barriercmdcleave-cout" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Leaving screen.  the secondary screen should send clipboard data in
response to this message for those clipboards that it has grabbed
(i.e. has sent a barrierCmdCClipboard for and has not received a
barrierCmdCClipboard for with a greater sequence number) and that
were grabbed or have changed since the last leave.</dd>
</dl>
</div>
<div class="section" id="barriercmdcclipboard-cclp">
<h3>barrierCmdCClipboard “CCLP”<a class="headerlink" href="#barriercmdcclipboard-cclp" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">id,</span> <span class="pre">int32_t</span> <span class="pre">seq</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Grab clipboard. Sent by screen when some other app on that screen
grabs a clipboard.</p>
<p><code class="docutils literal notranslate"><span class="pre">id</span></code>  = the clipboard identifier</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">seq</span></code> = sequence number. Client must use the sequence number passed in
the most recent barrierCmdCEnter.  the server always sends 0.</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdcscreensaver-csec">
<h3>barrierCmdCScreenSaver   “CSEC”<a class="headerlink" href="#barriercmdcscreensaver-csec" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">started</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Screensaver change.</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">started</span></code> = Screensaver on primary has started (1) or closed (0)</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdcresetoptions-crop">
<h3>barrierCmdCResetOptions  “CROP”<a class="headerlink" href="#barriercmdcresetoptions-crop" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Reset options. Client should reset all of its options to their
defaults.</dd>
</dl>
</div>
<div class="section" id="barriercmdcinfoack-ciak">
<h3>barrierCmdCInfoAck   “CIAK”<a class="headerlink" href="#barriercmdcinfoack-ciak" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Resolution change acknowledgment. Sent by server in response to a
client screen’s barrierCmdDInfo. This is sent for every
barrierCmdDInfo, whether or not the server had sent a barrierCmdQInfo.</dd>
</dl>
</div>
<div class="section" id="barriercmdckeepalive-calv">
<h3>barrierCmdCKeepAlive “CALV”<a class="headerlink" href="#barriercmdckeepalive-calv" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Keep connection alive. Sent by the server periodically to verify
that connections are still up and running.  clients must reply in
kind on receipt.  if the server gets an error sending the message or
does not receive a reply within a reasonable time then the server
disconnects the client.  if the client doesn’t receive these (or any
message) periodically then it should disconnect from the server.  the
appropriate interval is defined by an option.</dd>
</dl>
</div>
<div class="section" id="barriercmddkeydown-dkdn">
<h3>barrierCmdDKeyDown   “DKDN”<a class="headerlink" href="#barriercmddkeydown-dkdn" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">keyid,</span> <span class="pre">int16_t</span> <span class="pre">modifier</span> <span class="pre">[,int16_t</span> <span class="pre">button]</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Key pressed.</p>
<p><code class="docutils literal notranslate"><span class="pre">keyid</span></code> = X11 key id</p>
<p><code class="docutils literal notranslate"><span class="pre">modified</span></code> = modified mask</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">button</span></code> = X11 Xkb keycode (optional)</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddkeyrepeat-dkrp">
<h3>barrierCmdDKeyRepeat “DKRP”<a class="headerlink" href="#barriercmddkeyrepeat-dkrp" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">keyid,</span> <span class="pre">int16_t</span> <span class="pre">modifier,</span> <span class="pre">int16_t</span> <span class="pre">repeat</span> <span class="pre">[,int16_t</span> <span class="pre">button]</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Key auto-repeat.</p>
<p><code class="docutils literal notranslate"><span class="pre">keyid</span></code> = X11 key id</p>
<p><code class="docutils literal notranslate"><span class="pre">modified</span></code> = modified mask</p>
<p><code class="docutils literal notranslate"><span class="pre">repeat</span></code>   = number of repeats</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">button</span></code>   = X11 Xkb keycode (optional)</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddkeyup-dkup">
<h3>barrierCmdDKeyUp “DKUP”<a class="headerlink" href="#barriercmddkeyup-dkup" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">keyid,</span> <span class="pre">int16_t</span> <span class="pre">modifier</span> <span class="pre">[,int16_t</span> <span class="pre">button]</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Key released.</p>
<p><code class="docutils literal notranslate"><span class="pre">keyid</span></code> = X11 key id</p>
<p><code class="docutils literal notranslate"><span class="pre">modified</span></code> = modified mask</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">button</span></code> = X11 Xkb keycode (optional)</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddmousedown-dmdn">
<h3>barrierCmdDMouseDown “DMDN”<a class="headerlink" href="#barriercmddmousedown-dmdn" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">button</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Mouse button pressed.</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">button</span></code> = button id</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddmouseup-dmup">
<h3>barrierCmdDMouseUp   “DMUP”<a class="headerlink" href="#barriercmddmouseup-dmup" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">button</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Mouse button release.</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">button</span></code> = button id</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddmousemove-dmmv">
<h3>barrierCmdDMouseMove “DMMV”<a class="headerlink" href="#barriercmddmousemove-dmmv" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">x,</span> <span class="pre">int16_t</span> <span class="pre">y</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Absolute mouse moved.</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">x</span></code>, <code class="docutils literal notranslate"><span class="pre">y</span></code> = absolute screen coordinates</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddmouserelmove-dmrm">
<h3>barrierCmdDMouseRelMove  “DMRM”<a class="headerlink" href="#barriercmddmouserelmove-dmrm" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">x,</span> <span class="pre">int16_t</span> <span class="pre">y</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Relative mouse moved.</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">x</span></code>, <code class="docutils literal notranslate"><span class="pre">y</span></code> = r relative screen coordinates</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddmousewheel-dmwm">
<h3>barrierCmdDMouseWheel “DMWM”<a class="headerlink" href="#barriercmddmousewheel-dmwm" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">x</span> <span class="pre">,</span> <span class="pre">int16_t</span> <span class="pre">y</span> <span class="pre">}</span></code> or <code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">y</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Mouse scroll. The delta should be +120 for one tick forward (away
from the user) or right and -120 for one tick backward (toward the
user) or left.</p>
<p><code class="docutils literal notranslate"><span class="pre">x</span></code> = x delta</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">y</span></code> = y delta</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddclipboard-dclp">
<h3>barrierCmdDClipboard “DCLP”<a class="headerlink" href="#barriercmddclipboard-dclp" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">id,</span> <span class="pre">int32_t</span> <span class="pre">seq,</span> <span class="pre">int8_t</span> <span class="pre">mark,</span> <span class="pre">char</span> <span class="pre">*data</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Clipboard data.</p>
<p><code class="docutils literal notranslate"><span class="pre">id</span></code>  = clipboard id</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">seq</span></code> = sequence number. The sequence number is 0 when sent by the
server.  Client screens should use the/ sequence number from
the most recent barrierCmdCEnter.</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddsetoptions-dsop">
<h3>barrierCmdDSetOptions “DSOP”<a class="headerlink" href="#barriercmddsetoptions-dsop" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int32</span> <span class="pre">t</span> <span class="pre">nb,</span> <span class="pre">{</span> <span class="pre">int32_t</span> <span class="pre">id,</span> <span class="pre">int32_t</span> <span class="pre">val</span> <span class="pre">}[]</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Set options. Client should set the given option/value pairs.</p>
<p><code class="docutils literal notranslate"><span class="pre">nb</span></code>  = numbers of <code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">id,</span> <span class="pre">val</span> <span class="pre">}</span></code> entries</p>
<p><code class="docutils literal notranslate"><span class="pre">id</span></code>  = option id</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">val</span></code> = option new value</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmddfiletransfer-dftr">
<h3>barrierCmdDFileTransfer “DFTR”<a class="headerlink" href="#barriercmddfiletransfer-dftr" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int8_t</span> <span class="pre">mark,</span> <span class="pre">char</span> <span class="pre">*content</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Transfer file data.</p>
<ul class="last simple">
<li><code class="docutils literal notranslate"><span class="pre">mark</span></code> = 0 means the content followed is the file size</li>
<li>1 means the content followed is the chunk data</li>
<li>2 means the file transfer is finished</li>
</ul>
</dd>
</dl>
</div>
<div class="section" id="barriercmdddraginfo-ddrg">
<h3>barrierCmdDDragInfo  “DDRG”<a class="headerlink" href="#barriercmdddraginfo-ddrg" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">nb,</span> <span class="pre">char</span> <span class="pre">*content</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Drag information.</p>
<p><code class="docutils literal notranslate"><span class="pre">nb</span></code>  = number of dragging objects</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">content</span></code> = object’s directory</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdqinfo-qinf">
<h3>barrierCmdQInfo  “QINF”<a class="headerlink" href="#barriercmdqinfo-qinf" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd><p class="first">Query screen info</p>
<p class="last">Client should reply with a barrierCmdDInfo</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdeincompatible-eicv">
<h3>barrierCmdEIncompatible  “EICV”<a class="headerlink" href="#barriercmdeincompatible-eicv" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd><code class="docutils literal notranslate"><span class="pre">{</span> <span class="pre">int16_t</span> <span class="pre">nb,</span> <span class="pre">major</span> <span class="pre">*minor</span> <span class="pre">}</span></code></dd>
<dt>Description:</dt>
<dd><p class="first">Incompatible version.</p>
<p><code class="docutils literal notranslate"><span class="pre">major</span></code> = major version</p>
<p class="last"><code class="docutils literal notranslate"><span class="pre">minor</span></code> = minor version</p>
</dd>
</dl>
</div>
<div class="section" id="barriercmdebusy-ebsy">
<h3>barrierCmdEBusy  “EBSY”<a class="headerlink" href="#barriercmdebusy-ebsy" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Name provided when connecting is already in use.</dd>
</dl>
</div>
<div class="section" id="barriercmdeunknown-eunk">
<h3>barrierCmdEUnknown   “EUNK”<a class="headerlink" href="#barriercmdeunknown-eunk" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Unknown client. Name provided when connecting is not in primary’s
screen configuration map.</dd>
</dl>
</div>
<div class="section" id="barriercmdebad-ebad">
<h3>barrierCmdEBad   “EBAD”<a class="headerlink" href="#barriercmdebad-ebad" title="Permalink to this headline">¶</a></h3>
<dl class="docutils">
<dt>Direction:</dt>
<dd>server -&gt; client</dd>
<dt>Parameters:</dt>
<dd>None</dd>
<dt>Description:</dt>
<dd>Protocol violation. Server should disconnect after sending this
message.</dd>
</dl>
</div>
</div>
</div>

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