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<h1 class="lined-header"><span>ranch_tcp(3)</span></h1>
<div class="sect1">
<h2 id="_name">Name</h2>
<div class="sectionbody">
<div class="paragraph"><p>ranch_tcp - TCP transport module</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_description">Description</h2>
<div class="sectionbody">
<div class="paragraph"><p>The <code>ranch_tcp</code> module implements a TCP Ranch transport.</p></div>
<div class="paragraph"><p>Note that due to bugs in OTP up to at least R16B02, it is
recommended to disable async threads when using the
<code>sendfile</code> function of this transport, as it can make
the threads stuck indefinitely.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_types">Types</h2>
<div class="sectionbody">
<div class="sect2">
<h3 id="_opt">opt()</h3>
<div class="listingblock">
<div class="content"><!-- Generator: GNU source-highlight 3.1.8
by Lorenzo Bettini
http://www.lorenzobettini.it
http://www.gnu.org/software/src-highlite -->
<pre><tt><span style="font-weight: bold"><span style="color: #000000">opt</span></span>() <span style="color: #990000">=</span> {<span style="color: #FF6600">backlog</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">buffer</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">delay_send</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">dontroute</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">exit_on_close</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">fd</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">high_msgq_watermark</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">high_watermark</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| <span style="color: #FF6600">inet</span>
| <span style="color: #FF6600">inet6</span>
| {<span style="color: #FF6600">ip</span>, <span style="font-weight: bold"><span style="color: #000000">inet:ip_address</span></span>()}
| {<span style="color: #FF6600">keepalive</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">linger</span>, {<span style="font-weight: bold"><span style="color: #000000">boolean</span></span>(), <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}}
| {<span style="color: #FF6600">low_msgq_watermark</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">low_watermark</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">nodelay</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">port</span>, <span style="font-weight: bold"><span style="color: #000000">inet:port_number</span></span>()}
| {<span style="font-weight: bold"><span style="color: #000080">priority</span></span>, <span style="font-weight: bold"><span style="color: #000080">integer</span></span>()}
| {<span style="color: #FF6600">raw</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>(), <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>(), <span style="font-weight: bold"><span style="color: #000080">binary</span></span>()}
| {<span style="color: #FF6600">recbuf</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">send_timeout</span>, <span style="font-weight: bold"><span style="color: #000000">timeout</span></span>()}
| {<span style="color: #FF6600">send_timeout_close</span>, <span style="font-weight: bold"><span style="color: #000000">boolean</span></span>()}
| {<span style="color: #FF6600">sndbuf</span>, <span style="font-weight: bold"><span style="color: #000000">non_neg_integer</span></span>()}
| {<span style="color: #FF6600">tos</span>, <span style="font-weight: bold"><span style="color: #000080">integer</span></span>()}</tt></pre></div></div>
<div class="paragraph"><p>Listen options.</p></div>
<div class="paragraph"><p>This does not represent the entirety of the options that can
be set on the socket, but only the options that may be
set independently of protocol implementation.</p></div>
</div>
<div class="sect2">
<h3 id="_opts_opt">opts() = [opt()]</h3>
<div class="paragraph"><p>List of listen options.</p></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_option_descriptions">Option descriptions</h2>
<div class="sectionbody">
<div class="paragraph"><p>None of the options are required.</p></div>
<div class="paragraph"><p>Please consult the <code>gen_tcp</code> and <code>inet</code> manuals for a more
thorough description of these options. This manual only aims
to provide a short description along with what the defaults
are. Defaults may be different in Ranch compared to <code>gen_tcp</code>.
Defaults are given next to the option name.</p></div>
<div class="dlist"><dl>
<dt class="hdlist1">
backlog (1024)
</dt>
<dd>
<p>
Max length of the queue of pending connections.
</p>
</dd>
<dt class="hdlist1">
buffer
</dt>
<dd>
<p>
Size of the buffer used by the Erlang driver. Default is system-dependent.
</p>
</dd>
<dt class="hdlist1">
delay_send (false)
</dt>
<dd>
<p>
Always queue packets before sending, to send fewer, larger packets over the network.
</p>
</dd>
<dt class="hdlist1">
dontroute (false)
</dt>
<dd>
<p>
Don’t send via a gateway, only send to directly connected hosts.
</p>
</dd>
<dt class="hdlist1">
exit_on_close (true)
</dt>
<dd>
<p>
Disable to allow sending data after a close has been detected.
</p>
</dd>
<dt class="hdlist1">
fd
</dt>
<dd>
<p>
File descriptor of the socket, if it was opened externally.
</p>
</dd>
<dt class="hdlist1">
high_msgq_watermark (8192)
</dt>
<dd>
<p>
Limit in the amount of data in the socket message queue before the socket queue becomes busy.
</p>
</dd>
<dt class="hdlist1">
high_watermark (8192)
</dt>
<dd>
<p>
Limit in the amount of data in the ERTS socket implementation’s queue before the socket becomes busy.
</p>
</dd>
<dt class="hdlist1">
inet
</dt>
<dd>
<p>
Set up the socket for IPv4.
</p>
</dd>
<dt class="hdlist1">
inet6
</dt>
<dd>
<p>
Set up the socket for IPv6.
</p>
</dd>
<dt class="hdlist1">
ip
</dt>
<dd>
<p>
Interface to listen on. Listen on all interfaces by default.
</p>
</dd>
<dt class="hdlist1">
keepalive (false)
</dt>
<dd>
<p>
Enable sending of keep-alive messages.
</p>
</dd>
<dt class="hdlist1">
linger ({false, 0})
</dt>
<dd>
<p>
Whether to wait and how long to flush data sent before closing the socket.
</p>
</dd>
<dt class="hdlist1">
low_msgq_watermark (4096)
</dt>
<dd>
<p>
Amount of data in the socket message queue before the socket queue leaves busy state.
</p>
</dd>
<dt class="hdlist1">
low_watermark (4096)
</dt>
<dd>
<p>
Amount of data in the ERTS socket implementation’s queue before the socket leaves busy state.
</p>
</dd>
<dt class="hdlist1">
nodelay (true)
</dt>
<dd>
<p>
Whether to enable TCP_NODELAY.
</p>
</dd>
<dt class="hdlist1">
port (0)
</dt>
<dd>
<p>
TCP port number to listen on. 0 means a random port will be used.
</p>
</dd>
<dt class="hdlist1">
priority (0)
</dt>
<dd>
<p>
Priority value for all packets to be sent by this socket.
</p>
</dd>
<dt class="hdlist1">
recbuf
</dt>
<dd>
<p>
Minimum size of the socket’s receive buffer. Default is system-dependent.
</p>
</dd>
<dt class="hdlist1">
send_timeout (30000)
</dt>
<dd>
<p>
How long the send call may wait for confirmation before returning.
</p>
</dd>
<dt class="hdlist1">
send_timeout_close (true)
</dt>
<dd>
<p>
Whether to close the socket when the confirmation wasn’t received.
</p>
</dd>
<dt class="hdlist1">
sndbuf
</dt>
<dd>
<p>
Minimum size of the socket’s send buffer. Default is system-dependent.
</p>
</dd>
<dt class="hdlist1">
tos
</dt>
<dd>
<p>
Value for the IP_TOS IP level option. Use with caution.
</p>
</dd>
</dl></div>
<div class="paragraph"><p>In addition, the <code>raw</code> option can be used to set system-specific
options by specifying the protocol level, the option number and
the actual option value specified as a binary. This option is not
portable. Use with caution.</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_exports">Exports</h2>
<div class="sectionbody">
<div class="paragraph"><p>None.</p></div>
</div>
</div>
</div>
<div class="span3 sidecol">
<h3>
Ranch
1.2
Function Reference
</h3>
<ul>
<li><a href="/docs/en/ranch/1.2/guide">User Guide</a></li>
<li><a href="/docs/en/ranch/1.2/manual">Function Reference</a></li>
</ul>
<h4 id="docs-nav">Navigation</h4>
<h4>Version select</h4>
<ul>
<li><a href="/docs/en/ranch/1.3/manual">1.3</a></li>
<li><a href="/docs/en/ranch/1.2/manual">1.2</a></li>
</ul>
</div>
</div>
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