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                <h1>IPC::Msg</h1>
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            <h1>IPC::Msg</h1>


  <!--    -->
<ul><li><a href="#NAME">NAME</a><li><a href="#SYNOPSIS">SYNOPSIS</a><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#METHODS">METHODS</a><li><a href="#SEE-ALSO">SEE ALSO</a><li><a href="#AUTHORS">AUTHORS</a><li><a href="#COPYRIGHT">COPYRIGHT</a></ul><a name="NAME"></a><h1>NAME</h1>
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<p>IPC::Msg - SysV Msg IPC object class</p>
<a name="SYNOPSIS"></a><h1>SYNOPSIS</h1>
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<pre class="verbatim"><ol><li>    <a class="l_k" href="../functions/use.html">use</a> <span class="w">IPC::SysV</span> <span class="q">qw(IPC_PRIVATE S_IRUSR S_IWUSR)</span><span class="sc">;</span></li><li>    <a class="l_k" href="../functions/use.html">use</a> <span class="w">IPC::Msg</span><span class="sc">;</span></li><li></li><li>    <span class="i">$msg</span> = <span class="w">IPC::Msg</span><span class="w">-&gt;new</span><span class="s">(</span><span class="w">IPC_PRIVATE</span><span class="cm">,</span> <span class="w">S_IRUSR</span> | <span class="w">S_IWUSR</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$msg</span><span class="i">-&gt;snd</span><span class="s">(</span><span class="i">$msgtype</span><span class="cm">,</span> <span class="i">$msgdata</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$msg</span><span class="i">-&gt;rcv</span><span class="s">(</span><span class="i">$buf</span><span class="cm">,</span> <span class="n">256</span><span class="s">)</span><span class="sc">;</span></li><li></li><li>    <span class="i">$ds</span> = <span class="i">$msg</span><span class="i">-&gt;stat</span><span class="sc">;</span></li><li></li><li>    <span class="i">$msg</span><span class="i">-&gt;remove</span><span class="sc">;</span></li></ol></pre><a name="DESCRIPTION"></a><h1>DESCRIPTION</h1>
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<p>A class providing an object based interface to SysV IPC message queues.</p>
<a name="METHODS"></a><h1>METHODS</h1>
<ul>
<li><a name="new-(-KEY-%2c-FLAGS-)"></a><b>new ( KEY , FLAGS )</b>
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<p>Creates a new message queue associated with <code class="inline"><span class="w">KEY</span></code>
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. A new queue is
created if</p>
<ul>
<li>
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<p><code class="inline"><span class="w">KEY</span></code>
 is equal to <code class="inline"><span class="w">IPC_PRIVATE</span></code>
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</p>
</li>
<li>
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<p><code class="inline"><span class="w">KEY</span></code>
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 does not already have a message queue associated with
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it, and <code class="inline"><i>FLAGS</i> &amp; IPC_CREAT</code> is true.</p>
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</li>
</ul>
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<p>On creation of a new message queue <code class="inline"><span class="w">FLAGS</span></code>
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 is used to set the
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permissions.  Be careful not to set any flags that the Sys V
IPC implementation does not allow: in some systems setting
execute bits makes the operations fail.</p>
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</li>
<li><a name="id"></a><b>id</b>
<p>Returns the system message queue identifier.</p>
</li>
<li><a name="rcv-(-BUF%2c-LEN-%5b%2c-TYPE-%5b%2c-FLAGS-%5d%5d-)"></a><b>rcv ( BUF, LEN [, TYPE [, FLAGS ]] )</b>
<p>Read a message from the queue. Returns the type of the message read.
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See <i>msgrcv(2)</i>.  The BUF becomes tainted.</p>
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</li>
<li><a name="remove"></a><b>remove</b>
<p>Remove and destroy the message queue from the system.</p>
</li>
<li><a name="set-(-STAT-)"></a><b>set ( STAT )</b>
</li>
<li><a name="set-(-NAME-%3d%3e-VALUE-%5b%2c-NAME-%3d%3e-VALUE-...%5d-)"></a><b>set ( NAME =&gt; VALUE [, NAME =&gt; VALUE ...] )</b>
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<p><code class="inline"><span class="w">set</span></code>
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 will set the following values of the <code class="inline"><a class="l_k" href="../functions/stat.html">stat</a></code> structure associated
with the message queue.</p>
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<pre class="verbatim"><ol><li>    uid</li><li>    gid</li><li>    mode (oly the permission bits)</li><li>    qbytes</li></ol></pre><p><code class="inline"><span class="w">set</span></code>
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 accepts either a stat object, as returned by the <code class="inline"><a class="l_k" href="../functions/stat.html">stat</a></code> method,
or a list of <i>name</i>-<i>value</i> pairs.</p>
</li>
<li><a name="snd-(-TYPE%2c-MSG-%5b%2c-FLAGS-%5d-)"></a><b>snd ( TYPE, MSG [, FLAGS ] )</b>
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<p>Place a message on the queue with the data from <code class="inline"><span class="w">MSG</span></code>
 and with type <code class="inline"><span class="w">TYPE</span></code>
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.
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See <i>msgsnd(2)</i>.</p>
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</li>
<li><a name="stat"></a><b>stat</b>
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<p>Returns an object of type <code class="inline"><span class="w">IPC::Msg::stat</span></code>
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 which is a sub-class of
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<code class="inline"><span class="w">Class::Struct</span></code>
. It provides the following fields. For a description
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of these fields see you system documentation.</p>
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<pre class="verbatim"><ol><li>    <span class="w">uid</span></li><li>    <span class="w">gid</span></li><li>    <span class="w">cuid</span></li><li>    <span class="w">cgid</span></li><li>    <span class="w">mode</span></li><li>    <span class="w">qnum</span></li><li>    <span class="w">qbytes</span></li><li>    <span class="w">lspid</span></li><li>    <span class="w">lrpid</span></li><li>    <span class="w">stime</span></li><li>    <span class="w">rtime</span></li><li>    <span class="w">ctime</span></li></ol></pre></li>
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</ul>
<a name="SEE-ALSO"></a><h1>SEE ALSO</h1>
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<p><a href="../IPC/SysV.html">IPC::SysV</a>, <a href="../Class/Struct.html">Class::Struct</a></p>
<a name="AUTHORS"></a><h1>AUTHORS</h1>
<p>Graham Barr &lt;gbarr@pobox.com&gt;,
Marcus Holland-Moritz &lt;mhx@cpan.org&gt;</p>
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<a name="COPYRIGHT"></a><h1>COPYRIGHT</h1>
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<p>Version 2.x, Copyright (C) 2007-2013, Marcus Holland-Moritz.</p>
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<p>Version 1.x, Copyright (c) 1997, Graham Barr.</p>
<p>This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.</p>




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