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    <title>execline: the &lt;&lt; program</title>
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<p>
<a href="index.html">execline</a><br />
<a href="//skarnet.org/software/">Software</a><br />
<a href="//skarnet.org/">skarnet.org</a>
</p>

<h1> The <tt>&lt;&lt;</tt> program </h1>

<p>
<tt>&lt;&lt;</tt> runs a command with a certain string fed to a
file descriptor.
</p>

<h2> Interface </h2>

<pre>
     &lt;&lt; [ -d ] <em>fd</em> <em>string</em> <em>prog...</em>
</pre>

<ul>
 <li> <tt>&lt;&lt;</tt> execs into <em>prog...</em> with
<em>string</em> available on the <em>fd</em> file
descriptor. </li>
 <li> <em>string</em> must not contain a null character. </li>
</ul>

<h2> Options </h2>

<ul>
 <li> <tt>-d</tt>&nbsp;: run the process feeding <em>string</em> to <em>fd</em>
as a grandchild of <tt>&lt;&lt;</tt>. This is meant to prevent a zombie
from hanging around if <em>prog...</em> has read <em>string</em> and fails
to wait for its children.</li>
</ul>

<h2> Notes </h2>

<ul>
 <li> <tt>&lt;&lt;</tt> is meant to be used in place of the shell
<tt>&lt;&lt;</tt> construct, which includes <em>here-documents</em>
into scripts. </li>
</ul>

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