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<div class="sect1" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h2 class="title" style="clear: both"><a id="dbchannel_send_msg"></a>DbChannel::send_msg()</h2>
</div>
</div>
</div>
<pre class="programlisting">#include <db_cxx.h>
int
DbChannel::send_msg(Dbt *msg, u_int32_t nmsg, u_int32_t flags);</pre>
<p>
The <code class="methodname">DbChannel::send_msg()</code> method sends a
message on the message channel. The message is sent asynchronously;
the method does not wait for a response before returning. This
method usually completes quickly because it only waits for the
local TCP implementation to accept the bytes into its network data
buffer. However, this message could block briefly for longer
messages, and/or if the network data buffer is nearly full. This
method could even block indefinitely if the remote site is slow to
read.
</p>
<p>
If you want to block while waiting for a response from a remote
site, use the
<a class="xref" href="dbchannel_send_request.html" title="DbChannel::send_request()">DbChannel::send_request()</a>
method instead of this method.
</p>
<p>
The message sent by this method is received and handled at
remote sites using a message dispatch callback, which is configured
using the <a class="xref" href="repmgr_msg_dispatch.html" title="DbEnv::repmgr_msg_dispatch()">DbEnv::repmgr_msg_dispatch()</a>
method. Note that the DbChannel::send_msg() method may be used
within the the message dispatch callback on the remote site to send
a response or acknowledgement for messages that it receives and is
handling.
</p>
<p>
This method may be used on channels opened to any destination (see
the <a class="xref" href="repmgr_channel.html" title="DbEnv::repmgr_channel()">DbEnv::repmgr_channel()</a>
method for a list of potential destinations).
</p>
<p>
The <code class="methodname">DbChannel::send_msg()</code> <span>
<span>
method either returns a non-zero error value or throws an
exception that encapsulates a non-zero error value on
failure, and returns 0 on success.
</span>
</span>
</p>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp9331144"></a>Parameters</h3>
</div>
</div>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp9330496"></a>msg</h4>
</div>
</div>
</div>
<p>
Refers to an array of Dbt handles. For more
information, see
<a class="xref" href="dbt.html" title="Chapter 4. The Dbt Handle">
The Dbt Handle
</a>.
</p>
<p>
Any flags provided to the Dbt handles used in this
array are ignored.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp9308472"></a>nmsg</h4>
</div>
</div>
</div>
<p>
Indicates how many elements are contained in the
<code class="literal">msg</code> array.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp9327024"></a>flags</h4>
</div>
</div>
</div>
<p>
This parameter is currently unused, and must be
set to 0.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp9128424"></a>Errors</h3>
</div>
</div>
</div>
<p>
The <code class="methodname">DbChannel::send_msg()</code>
<span>
<span>
method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a>
exception, encapsulating one of the following non-zero errors, or return one
of the following non-zero errors:
</span>
</span>
</p>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp9339720"></a>DB_NOSERVER</h4>
</div>
</div>
</div>
<p>
A message was sent to a remote site that has not
configured a message dispatch call-back function.
Use the
<a class="xref" href="repmgr_msg_dispatch.html" title="DbEnv::repmgr_msg_dispatch()">DbEnv::repmgr_msg_dispatch()</a>
method at every site belonging to the replication group to configure a
message dispatch call-back function.
</p>
</div>
<div class="sect3" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="idp9337344"></a>EINVAL</h4>
</div>
</div>
</div>
<p>
If this method is called from a Base API application,
or if an invalid flag value or parameter was specified.
</p>
</div>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp9308104"></a>Class</h3>
</div>
</div>
</div>
<p>
<a class="link" href="env.html" title="Chapter 5. The DbEnv Handle">DbEnv</a>
</p>
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="idp9332224"></a>See Also</h3>
</div>
</div>
</div>
<p>
<a class="xref" href="rep.html#replist" title="Replication and Related Methods">Replication and Related Methods</a>
</p>
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