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

<h1> The <tt>emptyenv</tt> program </h1>

<p>
<tt>emptyenv</tt> empties the current environment, or cleans it up; then
executes a program.
</p>

<h2> Interface </h2>

<pre>
     emptyenv [ -p ] <em>prog...</em>
     emptyenv -c <em>prog...</em>
     emptyenv [ -o ] [ -P ] <em>prog...</em>
</pre>

<p>
By default, <tt>emptyenv</tt> unsets all environment variables, then
execs into <em>prog</em> with its arguments. Options control which
environment variables are unset.
</p>

<h2> Options </h2>

<ul>
 <li> <tt>-p</tt>&nbsp;: keep the <tt>PATH</tt> environment variable. </li>
 <li> <tt>-c</tt>&nbsp;: clean up. Do not empty the environment. Instead,
remove every variable used internally by the execline programs, to avoid
any interference with or information leakage to external programs. </li>
 <li> <tt>-o</tt>&nbsp;: <a href="el_pushenv.html#pop">pop</a> environment
variables starting with <tt>ELGETOPT_</tt>. You might want to do this
before executing a final program from a script that uses
<a href="elgetopt.html">elgetopt</a>. </li>
 <li> <tt>-P</tt>&nbsp;: <a href="el_pushenv.html#pop">pop</a> environment
variables starting with <tt>#</tt>, <tt>0</tt> to <tt>9</tt>, and
<tt>EXECLINE_</tt>. You might want to do this before executing a final program
from a script launched by <a href="execlineb.html">execlineb</a>. </li>
</ul>

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